MAPK regulates secondary metabolism and abiotic stress in horticultural and medicinal plants

Shuanglu Liu; Minghui Xing; Xiaojian Yin

doi:10.1093/hr/uhaf350

. 2025 Dec 17;13(3):uhaf350. doi: 10.1093/hr/uhaf350

MAPK regulates secondary metabolism and abiotic stress in horticultural and medicinal plants

Shuanglu Liu ^1,², Minghui Xing ^3,^✉, Xiaojian Yin ^4,^✉

PMCID: PMC12977962 PMID: 41821683

Abstract

Horticultural and medicinal plants are important for their economic and pharmacological value; however, their quality traits are severely affected by abiotic stresses. The mitogen-activated protein kinase (MAPK) cascade is an evolutionarily conserved signaling module that links abiotic stress signals to the regulation of plant quality traits. While the roles of MAPKs in growth, phytohormone signaling, and immunity are well established, a comprehensive review that integrates MAPK functions in abiotic stress responses and secondary metabolism, particularly in horticultural and medicinal plants, is still lacking. In this review, we systematically summarize (i) the composition, classification, and phylogenetic relationships of MAPKs in horticultural and medicinal plants; (ii) their mechanistic involvement in abiotic stress responses, particularly to salt, drought, and extreme temperatures; (iii) recent advances in understanding how MAPK-mediated signaling governs secondary metabolite accumulation; and (iv) a unified framework that presents MAPKs as a key bridge between stress responses and metabolic reprogramming. These insights provide a foundation for MAPK-targeted breeding and engineering strategies that enhance stress tolerance and improve quality traits in horticultural and medicinal plants through precise pathway manipulation.

Introduction

Horticultural and medicinal plants are high-value pillars of global agriculture; they sustain food supply and nutritional diversity through providing medicinal and functional compounds [1–3]. Their flavor, color, aroma, texture, and pharmacological activity depend on the fine coordination of specialized metabolic pathways, yet abiotic stresses such as drought, salt, and extreme temperatures often compromise yield and quality [3–5]. To cope with these challenges, plants have evolved tiered and efficient defense systems that can be categorized as tolerance, avoidance, escape, and recovery strategies [6–8]. Upon stress perception, plants rapidly trigger Ca²⁺ spikes and phosphorylation cascades, followed by membrane lipid/cell wall remodeling, accumulation of osmolytes and antioxidants, dynamic control of reactive oxygen species (ROS)/reactive nitrogen species (RNS), and transcriptional reprogramming, which ultimately culminate in adjustments in water balance, reconfiguration of photosynthesis and energy metabolism, and recalibration of growth, reproduction, and senescence [9–11].

Secondary metabolites carry dual value as determinants of product quality and as stress protectants [12]. Secondary metabolites are nonessential small molecules with pronounced species and spatiotemporal specificity, broadly classified by biosynthetic origin into three groups: alkaloids, typically nitrogenous and arising via shikimate- and 2-C-methyl-D-erythritol 4-phosphate (MEP)–related routes; terpenoids [2], derived from the C5 precursors isopentenyl pyrophosphate and dimethylallyl pyrophosphate (IPP and DMAPP) through the plastidial MEP pathway and the cytosolic mevalonate (MVA) pathway [12]; and phenylpropanoids and their derivatives, expanded by multistep modifications of a shikimate–phenylpropanoid core. Under adverse conditions, secondary metabolites enhance adaptation by inhibiting microbes and herbivores, scavenging ROS [13], fortifying cell walls, and modulating signaling (e.g. nicotine, camalexin, flavonoids), and they also provide key medicines for humans (e.g. artemisinin, paclitaxel, tanshinones, salvianolic acids) [2, 14]. Given that the potential metabolome may exceed a million entities and that accu mulation is multilayer-regulated, simple ‘single-enzyme, single-pathway’ models are inadequate to explain this complexity.

Among post-translational modifications (PTMs), protein phosphorylation serves as a pivotal mechanism that translates external stimuli into intracellular responses [15]. The canonical mitogen-activated protein kinase (MAPK) cascade, a highly conserved signaling module in eukaryotes, operates hierarchically: receptor activation triggers an MAPK kinase kinase (MAPKKK), which phosphorylates the conserved S/T–XXXXX–S/T motif of an MAPK kinase (MAPKK) [16]; the activated MAPKK then phosphorylates the Thr-any-Tyr (TXY) motif within an MAPK, thereby activating the terminal kinase [16, 17]. Based on the conserved TXY activation loop motif targeted by MAPKKs, plant MAPKs are divided into two major subfamilies: one carrying the Thr-Glu-Tyr (TEY) motif and the other the Thr-Asp-Tyr (TDY) motif (Group D) [16, 18]. The TEY-type subfamily can be further subdivided into Groups A–C [16–18], distinguished by specific structural and sequence characteristics. Once activated, MAPKs phosphorylate diverse downstream targets, including transcription factors (TFs), structural enzymes, and other regulatory proteins, thus relaying and amplifying extracellular cues with high precision [19, 20]. Through these phosphorylation events, MAPKs orchestrate essential processes such as plant growth and development, phytohormone signaling, responses to biotic and abiotic stresses, and the regulation of secondary metabolism [21–25].

In recent years, the roles of MAPKs in abiotic stress responses and secondary metabolite biosynthesis in horticultural and medicinal plants have attracted increasing attention. However, a comprehensive review of how MAPKs coordinate abiotic stress responses and reprogram secondary metabolism in these plants is still lacking; prior work often treats stress adaptation and metabolic control separately, with limited cross-species comparisons and module-level summaries. In this review, we present an integrated overview of: (i) the composition, classification, and phylogenetic relationships of MAPKs in horticultural and medicinal plants; (ii) the response and roles of MAPK cascades in mediating tolerance to salt, drought, and extreme temperatures (Tables 2 and 3); (iii) their functions and molecular mechanisms in regulating secondary-metabolite accumulation, including phenylpropanoids (anthocyanins, lignin, salvianolic acids, sakuranetin, forsythin), terpenoids (tanshinones, crocins, diterpenoid, linalool), alkaloids (monoterpenoid indole alkaloids, nicotine), and other defensive metabolites (phytoalexins, glucosinolates) (Table 4); and (iv) a unified framework positioning the MAPKs as a key bridge between stress resilience and metabolite accumulation. These insights provide actionable targets and strategies for MAPK-informed molecular breeding and metabolic engineering to jointly improve stress adaptability and quality traits.

Table 2.

Overview of MAPKs in abiotic stress responses across species

Abiotic stress	Species	MAPK	Up/Down	Reference
Drought	C. illinoinensis	CiPawMAPK1/3–1/13	Up	[55]
	C. morifolium	CmMAPK4.1/4.2/13	Up	[40]
	C. morifolium	CmMAPK9.2/16/18	Down	[40]
	F. tataricum	FtMAPK1/3	Up	[60]
	F. tataricum	FtMAPK4/9	Down	[60]
	F. vesca	FvMAPK5/8	Up	[61]
	Helianthus annuus	Leaves: HaMAPK3–2/11–1/14/1/6–2/19–1/18 Roots: HaMAPK3–2/9–2/11–2/13–2/23–2	Up	[62]
	H. annuus	Leaves: HaMAPK13–2 Roots: HaMAPK14	Down	[62]
	L. bicolor	LbMAPK10/18/19	Up	[37]
	L. bicolor	LbMAPK2/5/7/8/14/17/20	Down	[37]
	M. notabilis	MnMAPK3/4/6/7/8/9	Up	[57]
	M. notabilis	MnMAPK1/2	Down	[57]
	M. sativa	MsMAPK1/5/7/33/71/73	Up	[56]
	M. sativa	MsMAPK60/63/64	Down	[56]
Salt	A. chinensis	AcMAPK4/5/9/10/12/13/17	Up	[63]
	C. morifolium	CmMAPK3.2/13	Up	[40]
	F. tataricum	FtMAPK1/3/4/9	Down	[60]
	F. vesca	FvMAPK5/9/10/11/12	Up	[61]
	Glycyrrhiza uralensis	GuMAPK5/7/9/16/20–2/20–3	Up	[64]
	H. annuus	Leaves: HaMAPK11–1 Roots: HaMAPK2/6–1/14/23–2/17	Up	[62]
	H. annuus	Leaves: HaMAPK7/23–1 Roots: HaMAPK9–2/13–2	Down	[62]
	L. bicolor	LbMAPK10/12/18	Up	[37]
	L. bicolor	LbMAPK13/16/20	Down	[37]
	M. notabilis	MnMAPK1/9/10	Up	[57]
	M. notabilis	MnMAPK3/4/7/8	Down	[57]
	M. sativa	MsMAPK1/3/5/7/28/33/65/70/71/75	Up	[56]
	S. melongena	SmMAPK4.1	Up	[38]
Heat	A. chinensis	AcMAPK1/5/10/11/14/15/16/17/18	Up	[63]
	C. morifolium	CmMAPK1/9.1/9.2/16/18	Down	[40]
	F. vesca	FvMAPK3	Up	[61]
	M. notabilis	MnMAPK1/5/6/9	up	[57]
	M. notabilis	MnMAPK2/3/8/10	Down	[57]
Cold	A. chinensis	AcMAPK4/5/9/10/11/12	Up	[63]
	A. chinensis	AcMAPK2/6/7/13/18	Down	[63]
	C. morifolium	CmMAPK1/3.1/3.2/4.2/6/9.1/9.2/13/16/18	Up	[40]
	M. notabilis	MnMAPK1/5	Up	[57]
	M. notabilis	MnMAPK2/3/4/6/7/8	Down	[57]
	M. sativa	MsMAPK5/7/50/53/67/70/73/75/78	Up	[56]
	M. sativa	MsMAPK51/60	Down	[56]
	S. melongena	SmMAPK4.1	Up	[38]

Open in a new tab

Table 3.

Functions and mechanisms of MAPKs in plant abiotic stress

Abiotic stresses	Species	MAPKs	Substrates/Pathways	Reference
Drought	A. thaliana	AtMAPK1/2/7/14	AtMAPKKK17/18–MAPKK3–MAPK1/2/7/14	[65–67]
	B. platyphylla	BpMAPK3	BpWRKY53	[72]
	B. napus	BnMAPK1	Enhance antioxidant enzyme activity	[74]
	O. sativa	OsMAPK6	OsbZIP66	[35]
	O. sativa	OsMAPK3/6	OsMAPKK10.2-MAPK3/6	[68]
	P. trifoliata	PtrMAPK	ROS	[73]
	S. lycopersicum	SlMAPK1	ROS	[69]
	S. lycopersicum	SlMAPK3	Enhance antioxidant responses	[71]
	S. lycopersicum	SlMAPK4	JA/ET	[70]
Salt	A. thaliana	AtMAPK4/6	AtMAPKK2–MAPK4/6	[79]
	L. bicolor	LbMAPKs	Salt gland development	[37]
	M. domestica	MdMAPK3	MdWRKY17	[83]
	M. sativa	MsMAPK3	MsNAC73	[23]
	O. sativa	OsMAPK3/6	OsCPK5/13-OsMAPK3/6	[51]
	O. sativa	OsMAPK4	OsIPA1	[53]
	O. sativa	OsMAPK5	OsSERF1	[80]
	O. sativa	OsMAPK3/6	OsSIT1-MAPK3/6	[59]
	Z. mays	ZmMAPK7	ZmWRKY104	[81]
	Z. mays	ZmMAPK3	ZmGRF1	[84]
Heat	A. thaliana	AtMAPK3/6	AtIAA8	[90]
	C. annuum	CaMAPK1	JA/SA/ABA-CaMAPK1 -HSFA2 /70–1	[86]
	C. sativus	CsMAPK4	CsVQ10	[85]
	S. lycopersicum	SlMAPK1	SlSPRH1	[88]
	S. lycopersicum	SlMAPK1	Photosynthesis	[87]
	L. sativa	LsMAPK4	Unidentified	[89]
Cold	A. thaliana	AtMAPK3/4/6	AtICE1	[91, 92]
	I. batatas	IbMAPK3/6	IbSPF1	[95]
	O. sativa	OsMAPK3	OsMAPKK6-MAPK3- bHLH002-TPP1	[33]
	S. lycopersicum	SlMAPK1/2	SlBBX17-HY5-CBF1	[93]
	S. lycopersicum	SlMAPK7	ROS	[94]

Open in a new tab

Table 4.

MAPKs are involved in the regulation of plant secondary metabolites

Category	Secondary metabolites	Stimuli	Species	MAPK	Substrates/Pathways	Reference
Pigmentation and quality-related metabolites	Anthocyanins	N/Pi-insufficient	A. thaliana	AtMAPK3/6	AtMAPKK9-MAPK3/6-WRKY75	[27, 30]
	Anthocyanins	Light	A. thaliana	AtMAPK4	AtMYB75	[29]
	Anthocyanins	Low temperature	F. vesca	FvMAPK3	FvMYB10	[99]
	Anthocyanins	Light	M. domestica	MdMAPK4	MdMYB1	[98]
	Anthocyanins	Light	M. domestica	MdMAPK6	MdHY5	[97]
	Anthocyanins	Drought	M. domestica	MdMAPK6	WRKY17	[100]
	Anthocyanins	Light	S. melongena	SmMAPK4.1	SmMYB75	[38]
	Anthocyanins/ Isoflavones	Unidentified	Glycine max	GmMAPK6	GmMYB4	[101]
	Lignin	Pathogen	A. thaliana	AtMAPK3/6	AtMKP1-MAPK3/6-MYB4	[102]
	Lignin	Chitin	O. sativa	OsMAPK3	OsMAPKK4-MAPK3	[25]
	Lignin	Wounding	Populus dicot	PdMAPK6	PdMAPKK4-MAPK6-LTF1	[103]
Medicinally active components	Crocins	JA	Crocus sativus	CsMAPK6	CsMAPK6-WRKY38/34	[109]
	Diterpenoid/Linalool	M. oryzae	O. sativa	OsMAPK3	OsBDR1–MAPK3-TPS3/29	[34]
	Forsythin	Unidentified	F. suspensa	FsMAPK3	FsWRKY4	[107]
	Salvianolic acids	JA/SA	S. miltiorrhiza	SmMAPK3	SmJAZs	[105]
	Salvianolic acids	SA	S. miltiorrhiza	SmMAPK3	SmRAS1	[104]
	Tanshinones	JA	S. miltiorrhiza	SmMAPK3	SmWRKY33	[106]
	Terpenoids	Unidentified	B. platyphylla	BpMAPK6	BpWRKY6	[108]
Defense-related metabolites	Glucosinolates/ Camalexin	Botrytis cinerea	A. thaliana	AtMAPK3/6	AtMAPKKK3/5-MAPKK4/5 -MAPK3/6-WRKY33	[48, 51, 114]
	Monoterpenoid indole alkaloids	UV-B/JA	C. roseus	CrMAPK3	Unidentified	[115, 116]
	Nicotine	JA	N. tabacum	NtMAPK4	NtMEKK1b-MAPKK2a- MAPK4-ERF221	[117, 118]
	Phytoalexins	Pathogen	O. sativa	OsMAPK3	OsNAC29	[112]
	Phytoalexins	Chitin	O. sativa	OsMAPK6	OsMAPKK4-MAPK6- OsVQ8-WRKY10	[113]
	Phytoalexins	Chitin	O. sativa	OsMAPK3/6	OsMAPKK4-MAPK3/6	[25]
	Sakuranetin	Pathogen	O. sativa	OsMAPK6	OsWRKY67	[111]

Open in a new tab

Composition, classification, and phylogenetic relationships of MAPKs in model, horticultural, and medicinal plants

MAPKs represent one of the most conserved signaling modules in plants, translating extracellular cues into intracellular responses that control growth, development, and stress adaptation. Understanding their composition, classification, and evolutionary relationships across model, horticultural, and medicinal plants is therefore essential to uncover how conserved MAPK signaling frameworks have diversified to meet lineage-specific physiological demands. Despite extensive studies in Arabidopsis thaliana [26–30] and Oryza sativa [31–36], the organization and evolutionary patterns of MAPKs in many horticultural and medicinal plants remain poorly understood. In particular, whether these species possess lineage-specific MAPK subfamilies or motif innovations has not been systematically evaluated.

In our comparative genomic analysis of 21 representative species, we identified 10–26 MAPK members per genome (Table 1; Table S1). Across species, the D group consistently constituted the largest subclass, while Group C was often reduced or absent. Most MAPKs contained conserved TEY or TDY activation motifs, forming a stable structural backbone, whereas rare motif variants such as Thr-Asn-Tyr (TNY) in Limonium bicolor [37] and Met-Glu-Tyr (MEY) in Solanum melongena [38] imply clade-specific functional divergence.

Table 1.

Comparative landscape of MAPK family size, TXY motifs, and A–E subgroups across model, horticultural and medicinal plants

ID	Species	MAPK count	Subgroups					TXY Motifs
ID	Species	MAPK count	A	B	C	D	E	TXY Motifs
1	Actinidia chinensis	18	4	5	3	3	3	TEY/TDY
2	Aquilegia coerulea	11	5	3	0	3	0	TEY/TDY
3	A. thaliana	20	3	5	4	8	0	TEY/TDY
4	Camellia sinensis	21	6	4	3	8	0	TEY/TDY
5	C. illinoinensis	18	4	4	3	7	0	TEY/TDY
6	C. morifolium	11	3	3	1	4	0	TEY/TDY
7	C. sativus	14	2	3	1	8	0	TEY/TDY
8	Daucus carota	17	6	3	0	8	0	TEY/TDY
9	Eucommia ulmoides	13	2	4	2	5	0	TEY/TDY
10	Fagopyrum tataricum	16	2	4	1	9	0	TEY/TDY
11	Fragaria vesca	12	3	2	2	5	0	TEY/TDY
12	L. bicolor	20	3	6	4	7	0	TEY/TDY/TNY
13	M. domestica	26	5	6	5	10	0	TEY/TDY
14	M. notabilis	10	2	3	2	1	2	TEY/TDY
15	N. nucifera	15	4	4	1	6	0	TEY/TDY
16	O. sativa	17	2	2	2	11	0	TEY/TDY/MEY
17	S. miltiorrhiza	18	3	5	2	8	0	TEY/TDY
18	S. lycopersicum	16	3	4	2	7	0	TEY/TDY/MEY
19	S. melongena	16	3	4	1	8	0	TEY/TDY/MEY
20	V. vinifera	14	2	3	2	5	2	TEY/TDY
21	Ziziphus jujuba	10	2	2	1	5	0	TEY/TDY

Open in a new tab

Notes: MEY (Met-Glu-Tyr); TXY (Thr-Any amino acid-Tyr); TDY (Thr-Asp-Tyr); TEY (Thr-Glu-Tyr); TNY (Thr-Asn-Tyr). Groups A–E denote MAPK subgroups according to canonical plant MAPK classification.

A neighbor-joining (NJ) tree was constructed using MEGA 11 with 1000 bootstrap replicates [39]. Phylogenetic reconstruction of seven representative species—A. thaliana [26], Chrysanthemum morifolium [40], Malus domestica [41], O. sativa [31], Salvia miltiorrhiza [42], Solanum lycopersicum [43], and Vitis vinifera [44]—clustered all MAPKs into five well-supported groups (A–E) (Fig. 1). Groups A and D contained the most members; Group A was conserved across all lineages, while Group D exhibited marked diversification in S. miltiorrhiza, M. domestica, and O. sativa, suggesting potential neofunctionalization.

Phylogenetic analysis of MAPKs in model, horticultural, and medicinal plants. Twenty *AtMAPKs* from *A. thaliana*, 11 *CmMAPKs* from *C. morifolium*, 26 *MdMAPKs* from *M. domestica*, 17 *OsMAPKs* from *O. sativa*, 18 *SmMAPKs* from *S. miltiorrhiza*, 16 *SlMAPKs* from *S. lycopersicum*, and 14 *VvMAPKs* from *V. vinifera* were analyzed. An NJ tree was constructed using MEGA 11 with 1000 bootstrap replicates. Node color gradients indicate bootstrap support values (0.5–1.0, reflecting branch reliability); and connecting lines illustrate phylogenetic relationships among *MAPKs*.

Together, these findings reveal a conserved TEY/TDY-based MAPK backbone combined with lineage-specific expansions and occasional motif innovations, reflecting both evolutionary stability and adaptive diversification. Future research should focus on integrating functional and structural analyses to determine how MAPK diversification contributes to species-specific stress signaling and metabolic specialization in horticultural and medicinal plants.

The response, function, and regulatory network of MAPK in abiotic stress

MAPKs involved in abiotic stress response

MAPK cascades act as central hubs translating abiotic stress signals, such as drought, salt, and extreme temperature, into transcriptional and metabolic adjustments that sustain cellular homeostasis [8, 11, 45–47]. While the roles of MAPKs in stress signaling are well characterized in model plants like A. thaliana and O. sativa, their diversity and functional specialization in horticultural and medicinal plants remain less understood [26, 27, 29, 30, 35, 48–54]. Recent transcriptomic analyses across multiple species reveal that most MAPK genes respond dynamically to abiotic stresses, showing species- and organ-specific expression patterns (Table 2). In general, drought and salt trigger broad transcriptional activation, whereas temperature stress elicits more heterogeneous responses—high temperature inducing widespread upregulation and low temperature producing both activation and repression depending on the species. For instance, several MAPKs in Carya illinoinensis [55], C. morifolium [40], Medicago sativa [56], and Morus notabilis [57] were strongly induced under drought or salt conditions, reflecting a conserved stress-responsive module. Such pervasive responsiveness underscores MAPKs as critical mediators linking environmental cues to adaptive physiological remodeling. In summary, MAPK genes in horticultural and medicinal plants exhibit extensive yet differentiated transcriptional regulation under abiotic stress, suggesting lineage-specific specialization built upon a conserved signaling backbone. Future studies should move beyond expression profiling to integrate functional genomics and phosphoproteomic approaches, aiming to elucidate how specific MAPK modules coordinate crosstalk among Ca²⁺, ROS, and phytohormone pathways to fine-tune stress resilience [58, 59].

MAPK-mediated regulation of phytohormone signaling and ROS homeostasis enhances plant drought tolerance

Drought represents one of the most pervasive abiotic stresses that severely constrain plant productivity and survival [45, 49]. In horticultural and medicinal plants, which are often cultivated under variable environments, drought not only restricts biomass accumulation but also affects secondary metabolite profiles critical for product quality [6, 11]. Understanding the molecular mechanisms that mediate drought tolerance is thus fundamental for improving both yield and quality. Among various signaling modules, MAPK cascades serve as evolutionarily conserved sensors and transducers that translate drought-induced cellular perturbations into adaptive transcriptional and metabolic responses. Although MAPK cascades have been extensively characterized in model species, the specific molecular circuits by which they integrate phytohormone signaling, ROS homeostasis, and secondary metabolism in horticultural and medicinal plants remain poorly understood. Particularly, it is unclear how different MAPK modules confer organ- or species-specific drought tolerance and how they connect early stress perception to downstream metabolic adaptation [11].

Recent studies across diverse species highlight that MAPKs act as central nodes linking phytohormone and redox signaling during drought (Fig. 2; Table 3). In Arabidopsis, the AtMAPKKK17/18–AtMAPKK3–AtMAPK1/2/7/14 cascade constitutes a core abscisic acid (ABA)-dependent pathway [65–67], where SNF1-RELATED PROTEIN KINASE 2 (SnRK2) activates the MAPK cascade and the TF ABSCISIC ACID-RESPONSIVE ELEMENT-BINDING PROTEIN 1 (AtAREB1) to amplify ABA responses [67]. A similar ABA-dependent cascade, OsMAPKK10.2–OsMAPK3, operates in rice (O. sativa) [68]. Furthermore, the CYSTEINE-RICH RECEPTOR-LIKE KINASE 14 (OsCRK14)–RECEPTOR-LIKE CYTOPLASMIC KINASE 57 (OsRLCK57)–OsMAPKKK10–OsMAPKK4–OsMAPK6 module enhances the stability of the ABA-responsive BASIC LEUCINE-ZIPPER TRANSCRIPTION FACTOR 66 (OsbZIP66) [35], thereby strengthening drought tolerance.

MAPK is involved in drought stress responses in horticultural and medicinal plants. Drought activates multiple MAPK cascades that integrate ABA, JA, and SA signaling with ROS homeostasis to enhance stress resilience. In the ABA pathway, OsMAPKK10.2–OsMAPK3 and OsCRK14–OsRLCK57–OsMAPKKK10–OsMAPKK4–OsMAPK6 stabilize OsbZIP66 and induce *OsLEAs*, while AtMAPKKK17/18–AtMAPKK3–AtMAPK1/2/7/14 represents a conserved ABA-dependent module. In the JA/ET/SA branch, SlMAPK1 and SlMAPK4 coordinate SA-, JA-, and ET-mediated ROS scavenging. In the ROS-regulatory branch, SlMAPK3 interacts with SlASR4 to remove ROS, and BpMAPK3 phosphorylates BpWRKY53 to activate *BpCHS* and flavonoid biosynthesis. Similarly, MAPK activation in *P. trifoliata* and *B. napus* enhances antioxidant enzyme activity. The figure is created with BioGDP.com [77]. ABA, abscisic acid; ET, ethylene; AREBs, ABA-RESPONSIVE ELEMENT-BINDING PROTEINS; CHS, CHALCONE SYNTHASE; JA, jasmonic acid; MAPK, MITOGEN-ACTIVATED PROTEIN KINASE; MAPKK, MAPK KINASE; MAPKKK, MAPK KINASE KINASE; SA, salicylic acid; ROS, reactive oxygen species; SnRK2, SNF1-RELATED PROTEIN KINASE 2; OsCRK14, CYSTEINE-RICH RECEPTOR-LIKE KINASE 14; OsRLCK57, RECEPTOR-LIKE CYTOPLASMIC KINASE 57; OsbZIP66, BASIC LEUCINE-ZIPPER TRANSCRIPTION FACTOR 66; OsLEAs, LATE EMBRYOGENESIS ABUNDANT PROTEINS; SlASR4, ABSCISIC ACID STRESS RIPENING PROTEIN 4.

MAPK–phytohormone crosstalk extends beyond ABA. In tomato (S. lycopersicum), SlMAPK1 promotes ROS scavenging and enhances drought tolerance. Its activation by salicylic acid (SA) and microbial metabolite albaflavenone further illustrates a microbe-induced MAPK–SA signaling collaboration [69], while SlMAPK4 links jasmonic acid (JA) and ethylene (ET) pathways [70], reflecting an integrated defense network. MAPKs also fine-tune drought tolerance by modulating ROS homeostasis and secondary metabolism. In tomato, SlMAPK3 interacts with the ABSCISIC ACID STRESS RIPENING PROTEIN 4 (SlASR4) to scavenge ROS, thereby enhancing drought tolerance [71]. In birch (Betula platyphylla), BpMAPK3 activates the TF BpWRKY53 to upregulate flavonoid biosynthetic genes, thereby maintaining ROS balance [72]. In Poncirus trifoliata and Brassica napus, MAPK activation enhances antioxidant enzyme activities, thereby improving drought tolerance [73, 74]. In S. miltiorrhiza, transcriptomic analyses revealed enrichment of MAPK signaling, phenylpropanoid metabolism, and tanshinone biosynthesis under drought, suggesting a direct regulatory role of SmMAPKs in secondary metabolism [75, 76].

Collectively, these studies reveal that MAPK cascades function as dual regulators in plant drought responses, integrating early stress signaling with metabolic control. By coordinating ABA and JA signaling, regulating ROS-scavenging systems, and modulating secondary metabolism, MAPKs act as pivotal molecular switches that connect environmental perception to adaptive reprogramming. Future research should focus on dissecting MAPK-specific modules that underlie organ- or species-specific drought tolerance, identifying direct MAPK substrates through phosphoproteomics, and elucidating how MAPK-mediated phosphorylation reshapes phytohormone sensitivity and metabolic fluxes. Integrating omics, gene editing, and biochemical approaches in horticultural and medicinal plants will clarify how MAPK diversification contributes to their evolutionary and functional adaptation to drought.

MAPK-mediated regulation of phytohormone signaling, ion homeostasis, and ROS detoxification enhances plant salt tolerance

Soil salinization, driven by improper irrigation, fertilizer misuse, and pollution, affects nearly 7% of global arable land and reduces yields by ~20% in irrigated areas [78]. Salt stress disrupts osmotic balance, ion homeostasis, and redox stability, severely impacting plant growth and productivity [6, 11]. In this context, MAPK cascades serve as conserved signaling modules that translate salt-induced cellular perturbations into adaptive transcriptional and physiological responses, making them key targets for improving salt tolerance (Fig. 3; Table 3). Although the MAPK-mediated salt signaling network has been elucidated in model species, its complexity in horticultural and medicinal plants remains largely unresolved. It is still unclear how MAPK modules integrate phytohormone regulation, ROS detoxification, ion balance, and developmental adaptation, or how specific cascades confer lineage- and tissue-specific salt tolerance.

Salt stress signal transduction mediated by MAPK in plants. Salt stress activates diverse MAPK cascades that integrate hormonal signaling, ion balance, and ROS regulation to promote salt tolerance. In Arabidopsis, the AtMAPKK2–AtMAPK4/6 module activates stress-responsive genes. In rice, OsMAPK5 phosphorylates OsSERF1 to induce *OsDREB2A* and *OsZFP179*, while OsMAPK4 suppresses salt tolerance by targeting OsIPA1. OsSIT1 activates OsMAPK3/6 to regulate ethylene signaling and ROS levels, and OsCPK5/13 forms a Ca²⁺-dependent regulatory loop with MAPKs and TFs. In horticultural and medicinal plants, MsMAPK3–MsNAC2–MsPG2 modulates cell wall remodeling in *M. sativa*, LbMAPK2 promotes salt gland development in *L. bicolor*, and MdMAPK3–WRKY17–HAK1 maintains Na⁺/K⁺ homeostasis in apple. The figure is created with BioGDP.com [77]. Ca²⁺, calcium ion; CPC, CAPRICE; CPK, CALCIUM-DEPENDENT PROTEIN KINASE; GL2, GLABRA2; HAK1, HIGH-AFFINITY K⁺ TRANSPORTER 1; K⁺, potassium ion; Na⁺, sodium ion; OsSIT1, SALT-INDUCED RECEPTOR-LIKE KINASE 1; OsSERF1, SALT-RESPONSIVE ETHYLENE RESPONSE FACTOR 1; OsIPA1, IDEAL PLANT ARCHITECTURE 1; OsDREB2A, DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2A; OsZFP179, ZINC FINGER PROTEIN 179; SOS1, SALT OVERLY SENSITIVE 1; PG2, POLYGALACTURONASE 2; TTG1, TRANSPARENT TESTA GLABRA 1.

In Arabidopsis, the MAPKK2–MAPK4/6 module enhances salt tolerance by activating stress-responsive genes [79]. In rice, OsMAPK5 phosphorylates SALT-RESPONSIVE ETHYLENE RESPONSE FACTOR 1 (OsSERF1), thereby amplifying salt-responsive signaling [80]. Similarly, SALT-INDUCED RECEPTOR-LIKE KINASE 1 (OsSIT1) activates OsMAPK3/6, promoting ethylene biosynthesis and ROS accumulation [59], whereas OsMAPK4 negatively regulates salt tolerance by phosphorylating IDEAL PLANT ARCHITECTURE 1 (IPA1) [53]. Interestingly, CALCIUM-DEPENDENT PROTEIN KINASE 5/13 (OsCPK5/13) can directly activate OsMAPK3/6 independent of the canonical MAPKKs, further enhancing salt resilience [51]. Beyond model species, MAPK cascades are also crucial in horticultural and medicinal crops. In maize (Zea mays), ZmMAPK7 phosphorylates ZmWRKY104, which activates SUPEROXIDE DISMUTASE 4 (ZmSOD4) expression, increasing superoxide dismutase activity and reducing ROS accumulation [81].

In the recretohalophyte L. bicolor, LbMAPK2 participates in salt gland development and ion secretion [37]. In cotton (Gossypium hirsutum), the GhMEKK3/8/31–GhMAPKK5–GhMAPK11/23 cascade enhances salt tolerance by modulating WRKY-dependent transcription and adjusting both ABA and proline metabolism [82]. In apple, MdMAPK3 phosphorylates MdWRKY17 to activate the membrane transporter HIGH-AFFINITY K⁺ TRANSPORTER 1 (MdHAK1), maintaining Na⁺/K⁺ homeostasis [83]. Similarly, in alfalfa (M. sativa), MsMAPK3 phosphorylates MsNAC73, releasing repression on POLYGALACTURONASE 2 (MsPG2) and enhancing salt tolerance [23]. Meanwhile, the ZmMAPK3–ZmGRF1 module promotes maize growth by enhancing cell proliferation under salt stress [84]. Collectively, these studies reveal that MAPK cascades regulate plant salt tolerance through multilayered mechanisms encompassing phytohormone signaling, ROS detoxification, ion homeostasis, and developmental plasticity. The diversity of MAPK modules among species reflects both evolutionary conservation and adaptive specialization. Future studies should dissect MAPK–Ca²⁺–phytohormone crosstalk, identify direct MAPK substrates via phosphoproteomics, and characterize regulatory nodes using gene-editing approaches. Integrating transcriptomic, proteomic, and physiological analyses in horticultural and medicinal plants will clarify how MAPK diversification drives salt stress adaptation and support the breeding of salt-tolerant cultivars.

MAPK-mediated coordination of heat and cold signaling networks enhances plant thermotolerance

Temperature is a critical environmental determinant of plant growth and productivity. Both heat and cold extremes disrupt membrane integrity, protein homeostasis, and metabolic balance, ultimately leading to yield losses [6, 11]. MAPK cascades act as conserved signaling hubs that perceive temperature fluctuations and orchestrate downstream transcriptional and physiological adjustments to maintain cellular homeostasis (Fig. 4; Table 3). Despite significant advances in model species, the molecular coordination of MAPK-mediated heat and cold signaling remains poorly defined, particularly in horticultural and medicinal plants. It is unclear how distinct MAPK modules exert either antagonistic or synergistic roles under extreme temperatures, or how they balance growth–defense trade-offs during thermal adaptation.

MAPK-mediated regulation of plant tolerance to extreme temperature stress. **(A)** In cucumber, CsMAPK4 phosphorylates CsVQ10 to enhance heat tolerance; in pepper, CaMAPK1 activates *CaHSFA2* and *CaHSP70–1* through phytohormone and ROS signaling; and in tomato, SlMAPK1 phosphorylates SlSPRH1 to modulate photosynthesis and antioxidant defense. **(B)** Under cold stress, MAPK cascades converge on the ICE–CBF module. In Arabidopsis, the AtMAPKK4/5–AtMAPK3/6 pathway destabilizes ICE1, whereas the AtMEKK1–AtMAPKK2–AtMAPK4 cascade enhances freezing tolerance. In tomato, SlMAPK1/2 phosphorylates SlBBX17 to promote SlHY5-dependent CBF activation, while SlMAPK7 improves ROS scavenging via H₂O₂/Ca²⁺ signaling. In rice, OsMAPK3 phosphorylates OsbHLH002 to activate *OsTPP1* and trehalose biosynthesis; in sweet potato, IbMAPK3/6 phosphorylates IbSPF1 to enhance photosynthesis and membrane stability. The figure is created using BioGDP.com [77]. CaHSFA2, HEAT SHOCK TRANSCRIPTION FACTOR A2; CaHSP70–1, HEAT SHOCK PROTEIN 70–1; CBF, C-REPEAT BINDING FACTOR; CsVQ10, VALINE-GLUTAMINE MOTIF PROTEIN 10; HSF, HEAT SHOCK TRANSCRIPTION FACTOR; HSP, HEAT SHOCK PROTEINS; IbSPF1, STRESS-RESPONSIVE TRANSCRIPTION FACTOR 1; ICE, INDUCER OF CBF EXPRESSION; OsTPP1, TREHALOSE-6-PHOSPHATE PHOSPHATASE 1; SlSPRH1, SERINE–PROLINE-RICH PROTEIN HOMOLOG 1; SlBBX17, B-BOX PROTEIN 17; SlHY5, ELONGATED HYPOCOTYL 5; TPP1, TREHALOSE-6-PHOSPHATE PHOSPHATASE 1.

Under heat stress, MAPKs regulate thermotolerance through modulation of heat shock proteins, antioxidant defenses, photosynthesis, and developmental transitions (Fig. 4A). In cucumber (Cucumis sativus), CsMAPK4 interacts with VALINE-GLUTAMINE 10 (CsVQ10) as a phosphorylation substrate to positively regulate heat tolerance [85]. In pepper (Capsicum annuum), CaMAPK1 is induced by high temperature and multiple phytohormones (SA, JA, ABA), as well as Ralstonia solanacearum infection; silencing CaMAPK1 represses HEAT SHOCK TRANSCRIPTION FACTOR A2 (CaHSFA2) and CaHSP70–1, compromising thermotolerance and phytohormone/ROS signaling [86]. In tomato, proteomic analysis revealed that interference of SlMAPK1 alters the abundance of photosynthesis-related proteins, enhancing photosynthetic efficiency in knockdown plants—indicating a negative regulatory role [87]. Mechanistically, heat-activated SlMAPK1 phosphorylates SERINE-PROLINE-RICH PROTEIN HOMOLOG 1 (SlSPRH1), fine-tuning antioxidant defenses as a negative regulator of heat tolerance [88]. In lettuce (Lactuca sativa), silencing LsMAPK4 markedly suppresses heat-induced bolting, confirming its positive role in heat-promoted flowering [89]. In Arabidopsis, MAPK-mediated phosphorylation of AUXIN/INDOLE-3-ACETIC ACID (AtIAA8) inhibits floral development under high temperature, indicating a conserved mechanism for developmental control under thermal stress [90].

Cold signaling through MAPKs converges on the C-REPEAT BINDING FACTOR/INDUCER OF CBF EXPRESSION (CBF/ICE) module (Fig. 4B). In Arabidopsis, the AtMAPKK4/5–MAPK3/6 pathway phosphorylates and promotes degradation of AtICE1, thereby repressing CBF-mediated freezing tolerance [91, 92]. Conversely, the AtMEKK1–MAPKK2–MAPK4 module enhances cold tolerance by suppressing AtMAPK3/6 activity [91]. In tomato, SlMAPK1/2 phosphorylates B-BOX CONTAINING PROTEIN 17 (SlBBX17), strengthening its interaction with ELONGATED HYPOCOTYL 5 (SlHY5) to activate CBF-dependent acclimation [93]. Moreover, SlMAPK7, a cold-induced MAPK activated by H₂O₂ and Ca²⁺, enhances chilling tolerance via reducing ROS accumulation, elevating antioxidant enzyme activity, and promoting proline and soluble sugar accumulation [94]. In rice, OsMAPK3 interacts with the TF OsbHLH002, preventing its degradation by HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENES 1 (OsHOS1) and phosphorylating it to enhance transactivation of TREHALOSE-6-PHOSPHATE PHOSPHATASE 1 (OsTPP1), leading to trehalose accumulation and improved cold tolerance [33]. In sweet potato (Ipomoea batatas), IbMAPK3/IbMAPK6 phosphorylate and stabilize STRESS-RESPONSIVE TRANSCRIPTION FACTOR 1 (IbSPF1), enhancing photosynthesis and reducing lipid peroxidation under cold stress [95].

MAPK cascades function as multifaceted regulators of plant thermotolerance. Under heat stress, MAPKs control the expression of heat shock proteins, antioxidant enzymes, photosynthetic activity, and developmental transitions such as flowering. Under cold stress, MAPKs enhance tolerance primarily via the CBF/ICE module, osmolyte accumulation (trehalose, proline), and antioxidant activation. The coordinated yet sometimes opposing activities of distinct MAPK modules form a dynamic signaling network that enables plants to withstand thermal extremes. Future research should focus on elucidating the crosstalk between heat- and cold-activated MAPK modules, identifying their phosphorylation substrates, and clarifying how MAPKs integrate temperature sensing with phytohormone and metabolic responses. Functional genomics and phosphoproteomic approaches in horticultural and medicinal plants will be essential for understanding MAPK diversification and for developing thermotolerant cultivars.

MAPK regulates secondary metabolite biosynthesis

Understanding the regulatory roles of MAPK cascades in secondary metabolism is of great theoretical and practical importance for improving the quality, stress resistance, and bioactive compound production in horticultural and medicinal plants [2–4]. Under stress conditions, dynamic changes in signaling metabolites and TFs drive metabolic reprogramming [12]. As a central signaling hub, MAPK cascades play a pivotal role in coordinating the biosynthesis of phenylpropanoids, terpenoids, alkaloids, and other secondary metabolites. Despite advances in model species, key questions remain for horticultural and medicinal plants: how do distinct MAPK modules decode specific cues (temperature, light, drought, salt, and phosphate deficiency) to direct branch-specific flux? How does MAPK-dependent phosphorylation modulate TF activity and the assembly of MYB/WRKY/bHLH/ERF complexes, and adjust the stability of structural enzymes? To what extent are these MAPK–TF–enzyme circuits conserved versus lineage-specific?

Pigmentation and quality-related metabolites in horticultural plants

Evidence across multiple species indicates that MAPKs fine-tune pigment metabolism by post-translationally modifying key TFs and structural enzymes, thereby integrating environmental cues such as light, temperature, drought, and phosphate deficiency into pigment biosynthesis (Fig. 5A; Table 4) [12, 96]. Notably, in apple, light signaling activates two major axes, MdMAPK6–MdHY5 and MdMAPK4–MdMYB1, where MdMAPK6 phosphorylates and stabilizes MdHY5 to promote light-induced anthocyanin accumulation [97], while MdMAPK4 enhances MdMYB1 stability and coloration [98]. Similarly, in Arabidopsis, light-activated AtMAPK4 phosphorylates AtMYB75, which is essential for anthocyanin biosynthesis [29]. This regulation exhibits both activating and repressing patterns [27, 30]. Moreover, under phosphate- and nitrogen-deficient conditions, the AtMAPKK9–MAPK3/6 cascade promotes the expression of AtWRKY75 and represses the biosynthesis of anthocyanins by phosphorylating an unidentified TF in Arabidopsis [27, 30]. In contrast, in strawberry, low temperature induces FvMAPK3, which suppresses anthocyanin accumulation by phosphorylating FvMYB10 to reduce its transcriptional activity and CHALCONE SYNTHASE 1 (FvCHS1) to promote its proteasomal degradation [99]. In eggplant, SmMAPK4.1 interacts with SmMYB75 to negatively regulate high light-induced pigmentation, while knockout of SmMAPK4.1 alleviates this inhibition [38]. In drought-stressed apple, the MdMEK2–MdMAPK6–MdWRKY17–MdWRKY50 cascade enhances anthocyanin accumulation and oxidative stress tolerance by activating MdCHS [100]. Additionally, dark-induced MdMAPK4 phosphorylates ETHYLENE RESPONSE FACTOR 17 (MdERF17) to promote chlorophyll degradation during light/dark transitions, coordinating spatiotemporal pigmentation [98]. In soybean (Glycine max), the GmMAPK6–GmMYB4–MBW module reallocates flux between isoflavone and anthocyanin branches: GmMAPK6 phosphorylates and activates GmMYB4, and GmMYB4 modulates MYB–bHLH–WD40 (MBW) complex assembly to differentially regulate ISOFLAVONE SYNTHASE 2 (GmIFS2) and ANTHOCYANIDIN SYNTHASE 3 (GmANS3), increasing isoflavones while suppressing anthocyanins [101].

MAPK integrates environmental signals to regulate the biosynthesis of anthocyanin and lignin in horticultural plants. **(A)** MAPKs integrate environmental and nutritional cues such as light, drought, temperature, and nutrient deficiency to fine-tune pigment biosynthesis. In apple, MdMAPK6–MdHY5 and MdMAPK4–MdMYB1 promote light- and drought-induced anthocyanin accumulation. In Arabidopsis, light-activated AtMAPK4 phosphorylates AtMYB75, while the AtMAPKK9–AtMAPK3/6 cascade under low phosphate or nitrogen represses anthocyanin synthesis. FvMAPK3 in strawberry and SmMAPK4.1 in eggplant negatively regulate pigmentation by targeting FvMYB10 and SmMYB75, respectively. In soybean, GmMAPK6–GmMYB4 modulates the MBW complex to shift metabolic flux toward isoflavone rather than anthocyanin biosynthesis. **(B)** MAPKs also regulate lignin formation under stress. In Arabidopsis, AtMKP1 relieves AtMYB4-mediated repression of lignin genes. In poplar, PdMAPK6 phosphorylates PdLTF1 to promote its degradation and activate *4CL*. In rice, the OsMAPKK4–OsMAPK3/6 pathway redirects carbon flux to lignin and phytoalexin synthesis upon chitin stimulation. The figure is created using BioGDP.com [77]. 4CL, 4-COUMARATE: COA LIGASE; ANS, ANTHOCYANIDIN SYNTHASE; C4H, CINNAMATE-4-HYDROXYLASE; IFS, ISOFLAVONE SYNTHASE; MAMP, microbe-associated molecular pattern; PdLTF1, LIGNIN BIOSYNTHESIS-ASSOCIATED TRANSCRIPTION FACTOR 1.

MAPKs are also involved in lignin biosynthesis (Fig. 5B; Table 4). In Arabidopsis, MAPK PHOSPHATASE 1 (MKP1) regulates lignin biosynthesis by controlling MAPK-mediated phosphorylation of MYB4, thereby relieving its repression and promoting vascular lignification and disease resistance [102]. In rice, the fungal-type microbial-associated molecular pattern (MAMP) chitin activates the OsMAPKK4–OsMAPK3 cascade to reprogram defense metabolism. Activated OsMAPKK4 further redirects carbon flux from glycolysis toward secondary metabolism and induces cell death as well as diterpenoid and lignin synthesis [25]. Similarly, in poplar, phosphorylation of LIGNIN BIOSYNTHESIS-ASSOCIATED TRANSCRIPTION FACTOR 1 (PdLTF1) by PdMAPK6 promotes its proteasomal degradation, relieving repression on lignin biosynthetic gene 4-COUMARATE: COA LIGASE (4CL) and initiating lignification under stress [103].

Bioactive metabolites in medicinal plants

As a model medicinal plant, S. miltiorrhiza produces two major classes of pharmacologically active compounds—lipophilic tanshinones and hydrophilic phenolic acids [42, 104]. MAPK cascades serve as a central link between environmental stimuli and these biosynthetic pathways. SmMAPK3 functions as the core regulator in two phytohormone-dependent phosphorylation modules (Fig. 6; Table 4): (i) the SA–SmMAPK3–ROSMARINIC ACID SYNTHASE 1 (SmRAS1) axis, where SA-induced phosphorylation of SmRAS1 enhances its stability and activity, promoting phenolic acid accumulation [104, 105]; and (ii) the SmMAPKK2/4/5/7–SmMAPK3–SmWRKY33 axis, which enhances tanshinone biosynthesis by alleviating JA-mediated repression and activating downstream tanshinone biosynthetic genes [106]. Similar MAPK–WRKY modules have been characterized in other medicinal plants. In Forsythia suspensa, the FsMAPK3–FsWRKY4 module likely regulates forsythin biosynthesis [107]; in birch, BpMAPK6–BpWRKY6 activates JA and terpene synthesis, enhancing insect resistance [108]; In saffron, JA activates the CsMAPK6–CsWRKY34/38 module, which coordinately regulates carotenoid and apocarotenoid biosynthesis, leading to enhanced crocin accumulation [109]. Similarly, during Magnaporthe oryzae infection in rice, the RECEPTOR-LIKE KINASE (RLK) BLAST DISEASE RESISTANCE 1 (OsBDR1) phosphorylates OsMAPK3, thereby upregulating the expression of TERPENE SYNTHASE 3 (OsTPS3) and OsTPS29, and promoting the synthesis of diterpenoids and linalool [34]. In addition, in salt-tolerant peppermint (Mentha piperita), MAPK activation modulates essential oil metabolism dynamically, maintaining the menthol/menthone ratio and ensuring stable productivity under salt stress conditions [110].

MAPK-mediated regulation of bioactive metabolite biosynthesis in medicinal plants. MAPK cascades connect environmental and hormonal signals with the biosynthesis of pharmacologically active compounds in medicinal plants. In *S. miltiorrhiza*, SmMAPK3 acts as a central regulator in two phosphorylation modules: (i) the SA–SmMAPK3–SmRAS1 axis, which promotes salvianolic acid accumulation via phosphorylation-induced stabilization of SmRAS1, and (ii) the SmMAPKK2/4/5/7–SmMAPK3–SmWRKY33 module, which activates tanshinone biosynthetic genes by relieving JA-mediated repression. Similar MAPK–WRKY signaling frameworks control specialized metabolism in other medicinal plants: FsMAPK3–FsWRKY4 in *F. suspensa* (forsythin biosynthesis), BpMAPK6–BpWRKY6 in birch (terpene synthesis), and CsMAPK6–CsWRKY34/38 in saffron (crocin biosynthesis). In rice, the RLK OsBDR1–MAPK3 module regulates terpenoid synthesis during *M. oryzae* infection. The figure is created using BioGDP.com [77]. RLKs, RECEPTOR-LIKE KINASES; SmRAS1, ROSMARINIC ACID SYNTHASE 1; SmCPS1, COPALYL DIPHOSPHATE SYNTHASE 1; SmKSL1, KAURENE SYNTHASE-LIKE 1.

Defensive metabolites

Defensive metabolites such as diterpenoid phytoalexins, flavonoids, and alkaloids are crucial components of plant innate immunity [13, 47]. In rice, the OsMAPKK4–OsMAPK3/6 cascade channels the MAMP signals toward diterpenoid phytoalexins [25]. The OsMAPK6–OsWRKY67–NARINGENIN 7-O-METHYLTRANSFERASE (OsNOMT) axis promotes sakuranetin production and resistance to false smut [111], while OsMAPK3–OsNAC29 phosphorylates and stabilizes OsNAC29 to activate OsTPS28 and CYTOCHROME P450 FAMILY 71 SUBFAMILY Z POLYPEPTIDE 2 (OsCYP71Z2), enhancing oryzalexin accumulation [112]. Additionally, OsWRKY10 interacts with OsVQ8, and upon pathogen-associated molecular patterns (PAMPs) perception, the activated OsMAPKK4–OsMAPK6 cascade phosphorylates OsVQ8, which in turn modulates diterpenoid phytoalexin (DP) biosynthesis [113]. In Arabidopsis, both the CPK5/CPK6 and MAPK3/MAPK6 signaling pathways promote the biosynthesis of indolic glucosinolates and camalexin during defense against Botrytis cinerea [48]. Infection by B. cinerea activates AtCPK5/CPK6 and AtMAPK3/6; these kinases cooperatively phosphorylate AtWRKY33, thereby enhancing its transcriptional activation of camalexin biosynthetic genes and boosting camalexin production [48, 51]. In parallel, a canonical AtMAPKKK3/5–AtMAPKK4/5–AtMAPK3/6–AtWRKY33 cascade also contributes to the regulation of camalexin biosynthesis [48, 51, 114] (Fig. 7; Table 4).

Among defense metabolites, alkaloids represent a primary chemical barrier due to their bitterness, toxicity, and antimicrobial activity. In Catharanthus roseus, the CrMAPKKK1–CrMAPKK1–CrMAPK3/6 cascade may phosphorylate CrMYC2 and OCTADECANOID-RESPONSIVE CATHARANTHUS AP2/ERF DOMAIN 3 (CrORCA3), enhancing transcriptional activation of monoterpenoid indole alkaloid (MIA) pathway genes and increasing vinblastine and vincristine accumulation [115, 116]. In Nicotiana tabacum, JA-induced NtMAPK4 interacts with PHOSPHATASE TYPE 2C B (NtPP2C2b), forming a ‘kinase–phosphatase’ regulatory module that fine-tunes AP2/ERF TF and nicotine biosynthesis [117, 118]. Thus, MAPK and PP2C modules precisely couple JA signaling with alkaloid biosynthesis through post-translational regulation of transcriptional hubs, providing actionable molecular targets for metabolic engineering (Fig. 7; Table 4).

Together, MAPK cascades form integrative nodes that couple environmental/phytohormone inputs to TFs (WRKY/MYB/bHLH/ERF) and structural enzymes (CHS, RAS, CYPs), orchestrating dynamic rewiring of pigment, pharmacological, and defensive pathways. The architecture is broadly conserved (MAPK–TF–pathway gene chains) yet exhibits species- and pathway-specific specialization. Priorities include defining stimulus specificity and crosstalk with photoreceptors/thermosensors/phytohormones; mapping direct phospho-targets via phosphoproteomics and interactomics; and leveraging these modules for metabolic engineering in horticultural and medicinal plants to rationally steer flux and enhance quality traits.

Conclusions

MAPK cascades are evolutionarily conserved switchboards that translate environmental and developmental cues into targeted transcriptional and metabolic outputs [8, 47]. In horticultural and medicinal plants—where yield, quality, and pharmacological value depend on both stress resilience and specialized metabolites—MAPKs couple abiotic stress tolerance (drought, salt, extreme temperature) with the regulation of phenylpropanoid, terpenoid, alkaloid, and N and S-containing pathways that determine coloration, flavor, defense, and bioactivity [8, 11, 47]. Across model, horticultural, and medicinal plants such as Arabidopsis [58], rice [119], tomato [69, 71, 120], and apple [83], converging evidence highlights MAPKs as pivotal regulators of abiotic stress tolerance. Under drought, salinity, and temperature extremes, MAPK cascades integrate upstream stress perception with downstream responses by modulating ABA-, JA-, SA-, and ET-dependent signaling pathways [59, 65, 69]. Through phosphorylation of TFs and antioxidant enzymes, MAPKs enhance ROS scavenging, adjust stomatal and osmotic balance, and stabilize cellular homeostasis to promote stress resilience. Beyond stress responses, MAPK modules also fine-tune the biosynthesis of secondary metabolites that determine pigmentation, flavor, defense, and pharmacological activity. Environmental and biotic cues—such as light, temperature, and pathogen attack—activate MAPKs, which in turn phosphorylate key TFs such as WRKY, MYB, bHLH, and ERF, and metabolic enzymes (e.g. CHS, CYPs, RAS). This regulation shapes metabolic flux through phenylpropanoid, terpenoid, alkaloid, and N and S-containing pathways. Together, these findings establish MAPKs as dual hubs that couple environmental adaptation with metabolic specialization, offering an integrated systems framework for understanding and improving stress tolerance, coloration, and bioactive compound accumulation in horticultural and medicinal crops.

Perspectives

Despite substantial progress in elucidating MAPK signaling, our understanding of its regulatory logic in horticultural and medicinal plants remains fragmentary. Current research is disproportionately focused on models and a few horticultural species under controlled conditions, while medicinal plants, field-like combined stresses, and spatial or temporal regulation remain underexplored. Functional studies are largely confined to Arabidopsis MAPK3/4/6, leaving the roles, hierarchies, and cross-species conservation of other MAPK members unresolved. The causal chain ‘MAPK-substrate-metabolic flux-phenotype’ also remains incomplete. Moreover, MAPKs rarely function alone: many substrates are cophosphorylated by other kinases such as CPKs or SnRK2s, creating complex signaling hierarchies whose coordination principles are still poorly defined [48, 51, 76]. Crosstalk with other PTMs (e.g. SUMOylation and ubiquitination) further shapes protein stability and activity, yet the combinatorial logic governing these interactions remains obscure [112, 121, 122]. Additionally, the constitutive activation of MAPK pathways often enhances stress tolerance at the cost of growth and productivity, highlighting the persistent challenge of mitigating growth–defense trade-offs in applied contexts.

Future research should therefore pursue integrative, multiscale, and context-dependent approaches to decode MAPK regulation and its translational potential. Systematic phenotyping and functional genomics—using CRISPR editing, inducible knockouts, and phosphoproteomic mapping—should be applied across representative species such as tomato, apple, and S. miltiorrhiza to resolve the dynamic relationships between MAPK modules, substrates, and metabolic outputs. Advanced multiomics combined with interpretable machine learning can further delineate stress-responsive network rewiring under realistic environmental conditions. Meanwhile, chemical ecology and chemical biology approaches may uncover natural microbial and rhizosphere metabolites (e.g. ‘albaflavenone-like’ activators) that fine-tune MAPK signaling, offering sustainable strategies for stress priming. Synthetic biology provides another frontier: engineering tissue- and stage-specific promoters, environmental switches, and modular ‘MAPK–TF–enzyme’ circuits could enable precise spatiotemporal activation of MAPK cascades, balancing defense with growth. Ultimately, integrating kinase cooperation, PTM crosstalk, and synthetic control will transform MAPK from passive signal relays into programmable regulatory nodes—driving coordinated improvements in stress resilience, metabolic efficiency, and quality formation in horticultural and medicinal plants [123].

Finally, by consolidating functional evidence across model, horticultural, and medicinal plants, this review outlines an MAPK-centered regulatory architecture that connects abiotic (drought, salinity, temperature, light, phytohormones, nutrients) and biotic (pathogen attack, insect herbivory) signals to metabolic adaptation. In this framework, the MAPKKK–MAPKK–MAPK cascade funnels upstream cues into three coordinated regulatory arms: (i) phytohormone crosstalk involving ABA, JA, SA, and ET pathways; (ii) phosphorylation of transcription factors such as WRKY, MYB, bHLH, ERF, and bZIP; and (iii) modulation of structural enzymes including CHS, CYPs, and RAS. Together, these arms orchestrate stress tolerance and the redistribution of metabolic flux across phenylpropanoid, terpenoid, alkaloid, and N- and S-containing pathways, resulting in concurrent improvements in stress resilience and the biosynthesis of high-value functional compounds. In summary, viewing MAPKs not only as mechanistic hubs but also as programmable design nodes provides a practical strategy to integrate stress signaling with metabolic enhancement—laying a conceptual foundation for rational engineering and breeding of resilient, high-quality horticultural and medicinal plants.

Supplementary Material

Web_Material_uhaf350

web_material_uhaf350.zip^{(83.8KB, zip)}

Acknowledgments

This work was partially supported by the National Natural Science Foundation of China (No. 82173918) and the Young Scientists Innovation Funds of the State Key Laboratory of Black Soils Conservation and Utilization, Northeast Institute of Geography and Agroecology (2023HTDGZ-QN-02).

Contributor Information

Shuanglu Liu, Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Jilin Da'an Agro-Ecosystem National Observation and Research Station, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; University of Chinese Academy of Sciences, Beijing 100049, China.

Minghui Xing, Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Jilin Da'an Agro-Ecosystem National Observation and Research Station, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.

Xiaojian Yin, Key Laboratory of Soybean Molecular Design Breeding, State Key Laboratory of Black Soils Conservation and Utilization, Jilin Da'an Agro-Ecosystem National Observation and Research Station, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.

Author contributions

X.Y. and M.X. conceived and designed the review. S.L. and M.X. drafted the manuscript, prepared the figures, and compiled the tables. X.Y. and M.X. critically revised the manuscript. All authors reviewed and approved the final version.

Conflicts of interest statement

The authors declare that they have no competing interests.

Supplementary material

Supplementary material is available at Horticulture Research online.

References

1. Mofokeng MM, Du Plooy CP, Araya HT. et al. Medicinal plant cultivation for sustainable use and commercialisation of high-value crops. S Afr J Sci. 2022;118:1–7 [Google Scholar]
2. Alami MM, Guo S, Mei Z. et al. Environmental factors on secondary metabolism in medicinal plants: exploring accelerating factors. Med Plant Biol. 2024;3:e016 [Google Scholar]
3. Tang H, Wang Q, Xie H. et al. The function of secondary metabolites in resisting stresses in horticultural plants. Fruit Res. 2024;4:e021 [Google Scholar]
4. Rabeh K, Hnini M, Oubohssaine M. A comprehensive review of transcription factor-mediated regulation of secondary metabolites in plants under environmental stress. Stress Biol. 2025;5:15 [Google Scholar]
5. Anzano A, Bonanomi G, Mazzoleni S. et al. Plant metabolomics in biotic and abiotic stress: a critical overview. Phytochem Rev. 2022;21:503–24 [Google Scholar]
6. Haak DC, Fukao T, Grene R. et al. Multilevel regulation of abiotic stress responses in plants. Front Plant Sci. 2017;8:1564. [DOI] [PMC free article] [PubMed] [Google Scholar]
7. Hanaka A, Majewska M, Jaroszuk-Ściseł J. Study of the influence of abiotic and biotic stress factors on horticultural plants. Horticulturae. 2021;8:6 [Google Scholar]
8. Chen X, Ding Y, Yang Y. et al. Protein kinases in plant responses to drought, salt, and cold stress. J Integr Plant Biol. 2021;63:53–78 [DOI] [PubMed] [Google Scholar]
9. Del Río LA. ROS and RNS in plant physiology: an overview. J Exp Bot. 2015;66:2827–37 [DOI] [PubMed] [Google Scholar]
10. Dong Q, Wallrad L, Almutairi BO. et al. Ca²⁺ signaling in plant responses to abiotic stresses. J Integr Plant Biol. 2022;64:287–300 [DOI] [PubMed] [Google Scholar]
11. Zhu JK. Abiotic stress signaling and responses in plants. Cell. 2016;167:313–24 [DOI] [PMC free article] [PubMed] [Google Scholar]
12. Liu S, Zhang Q, Kolli L. et al. Molecular networks of secondary metabolism accumulation in plants: current understanding and future challenges. Ind Crop Prod. 2023;201:116901 [Google Scholar]
13. Isah T. Stress and defense responses in plant secondary metabolites production. Biol Res. 2019;52:39. [DOI] [PMC free article] [PubMed] [Google Scholar]
14. Upadhyay AL, Lambat P, Borthakur M. Secondary metabolite production in plants: in response to biotic and abiotic stress factors. J Adv Zool. 2024;45:55–9 [Google Scholar]
15. Silva-Sanchez C, Li H, Chen S. Recent advances and challenges in plant phosphoproteomics. Proteomics. 2015;15:1127–41 [DOI] [PubMed] [Google Scholar]
16. Bigeard J, Hirt H. Nuclear signaling of plant MAPKs. Front Plant Sci. 2018;9:469. [DOI] [PMC free article] [PubMed] [Google Scholar]
17. Mohanta TK, Arora PK, Mohanta N. et al. Identification of new members of the MAPK gene family in plants shows diverse conserved domains and novel activation loop variants. BMC Genomics. 2015;16:58. [DOI] [PMC free article] [PubMed] [Google Scholar]
18. Cristina MS, Petersen M, Mundy J. Mitogen-activated protein kinase signaling in plants. Annu Rev Plant Biol. 2010;61:621–49 [DOI] [PubMed] [Google Scholar]
19. Li H, Chen N, Zhang H. et al. Multidimensional regulation of transcription factors: decoding the comprehensive signals of plant secondary metabolism. Front Plant Sci. 2025;16:1522278. [DOI] [PMC free article] [PubMed] [Google Scholar]
20. Zhang M, Su J, Zhang Y. et al. Conveying endogenous and exogenous signals: MAPK cascades in plant growth and defense. Curr Opin Plant Biol. 2018;45:1–10 [DOI] [PubMed] [Google Scholar]
21. Xu J, Zhang S. Mitogen-activated protein kinase cascades in signaling plant growth and development. Trends Plant Sci. 2015;20:56–64 [DOI] [PubMed] [Google Scholar]
22. Dong G, Gui Z, Yuan Y. et al. Expression analysis of the extensive regulation of mitogen-activated protein kinase (MAPK) family genes in buckwheat (Fagopyrum tataricum) during organ differentiation and stress response. Agronomy. 2024;14:2613 [Google Scholar]
23. You X, Fan N, Zhang Y. et al. The MsNAC73–MsMPK3 complex modulates salt tolerance and shoot branching of alfalfa via activating MsPG2 and MsPAE12 expressions. Plant Biotechnol J. 2025;23:5635–53 [DOI] [PMC free article] [PubMed] [Google Scholar]
24. Zhang Z, Liu H, Sun C. et al. A C2H2 zinc-finger protein OsZFP213 interacts with OsMAPK3 to enhance salt tolerance in rice. J Plant Physiol. 2018;229:100–10 [DOI] [PubMed] [Google Scholar]
25. Kishi-Kaboshi M, Okada K, Kurimoto L. et al. A rice fungal MAMP-responsive MAPK cascade regulates metabolic flow to antimicrobial metabolite synthesis. Plant J. 2010;63:599–612 [DOI] [PMC free article] [PubMed] [Google Scholar]
26. Colcombet J, Hirt H. Arabidopsis MAPKs: a complex signalling network involved in multiple biological processes. Biochem J. 2008;413:217–26 [DOI] [PubMed] [Google Scholar]
27. Lei L, Li Y, Wang Q. et al. Activation of MKK9-MPK3/MPK6 enhances phosphate acquisition in Arabidopsis thaliana. New Phytol. 2014;203:1146–60 [DOI] [PubMed] [Google Scholar]
28. Danquah A, de Zélicourt A, Boudsocq M. et al. Identification and characterization of an ABA-activated MAP kinase cascade in Arabidopsis thaliana. Plant J. 2015;82:232–44 [DOI] [PubMed] [Google Scholar]
29. Li S, Wang W, Gao J. et al. MYB75 phosphorylation by MPK4 is required for light-induced anthocyanin accumulation in Arabidopsis. Plant Cell. 2016;28:2866–83 [DOI] [PMC free article] [PubMed] [Google Scholar]
30. Luo J, Wang X, Feng L. et al. The mitogen-activated protein kinase kinase 9 (MKK9) modulates nitrogen acquisition and anthocyanin accumulation under nitrogen-limiting condition in Arabidopsis. Biochem Biophys Res Commun. 2017;487:539–44 [DOI] [PubMed] [Google Scholar]
31. Rohila JS, Yang Y. Rice mitogen-activated protein kinase gene family and its role in biotic and abiotic stress response. J Integr Plant Biol. 2007;49:751–9 [Google Scholar]
32. Chen J, Wang L, Yuan M. Update on the roles of rice MAPK cascades. Int J Mol Sci. 2021;22:1679. [DOI] [PMC free article] [PubMed] [Google Scholar]
33. Zhang Z, Li J, Li F. et al. OsMAPK3 phosphorylates OsbHLH002/OsICE1 and inhibits its ubiquitination to activate OsTPP1 and enhances rice chilling tolerance. Dev Cell. 2017;43:731–743.e5 [DOI] [PubMed] [Google Scholar]
34. Wang L, Xu J, Li L. et al. The OsBDR1-MPK3 module negatively regulates blast resistance by suppressing the jasmonate signaling and terpenoid biosynthesis pathway. Proc Natl Acad Sci USA. 2023;120:e2211102120 [DOI] [PMC free article] [PubMed] [Google Scholar]
35. Ye T, Wang H, Zhang L. et al. A novel OsCRK14–OsRLCK57–MAPK signaling module activates OsbZIP66 to confer drought resistance in rice. Mol Plant. 2025;18:1390–408 [DOI] [PubMed] [Google Scholar]
36. Wang F, Jing W, Zhang W. The mitogen-activated protein kinase cascade MKK1–MPK4 mediates salt signaling in rice. Plant Sci. 2014;227:181–9 [DOI] [PubMed] [Google Scholar]
37. Zhang C, Zhu Z, Jiang A. et al. Genome-wide identification of the mitogen-activated kinase gene family from Limonium bicolor and functional characterization of LbMAPK2 under salt stress. BMC Plant Biol. 2023;23:565. [DOI] [PMC free article] [PubMed] [Google Scholar]
38. Liao J, Dong Y, Hua Z. et al. Identification of eggplant SmMPK gene family and functional verification of SmMPK4.1. Horticulturae. 2024;10:239 [Google Scholar]
39. Tamura K, Stecher G, Kumar S. et al. MEGA11: molecular evolutionary genetics analysis version 11. Mol Biol Evol. 2021;38:3022–7 [DOI] [PMC free article] [PubMed] [Google Scholar]
40. Song A, Hu Y, Ding L. et al. Comprehensive analysis of mitogen-activated protein kinase cascades in chrysanthemum. Peer J. 2018;6:e5037 [DOI] [PMC free article] [PubMed] [Google Scholar]
41. Zhang S, Xu R, Luo X. et al. Genome-wide identification and expression analysis of MAPK and MAPKK gene family in Malus domestica. Gene. 2013;531:377–87 [DOI] [PubMed] [Google Scholar]
42. Xie Y, Ding M, Zhang B. et al. Genome-wide characterization and expression profiling of MAPK cascade genes in Salvia miltiorrhiza reveals the function of SmMAPK3 and SmMAPK1 in secondary metabolism. BMC Genomics. 2020;21:630. [DOI] [PMC free article] [PubMed] [Google Scholar]
43. Kong F, Wang J, Cheng L. et al. Genome-wide analysis of the mitogen-activated protein kinase gene family in Solanum lycopersicum. Gene. 2012;499:108–20 [DOI] [PubMed] [Google Scholar]
44. Çakır B, Kılıçkaya O. Mitogen-activated protein kinase cascades in Vitis vinifera. Front Plant Sci. 2015;6:556. [DOI] [PMC free article] [PubMed] [Google Scholar]
45. Feller U, Vaseva II. Extreme climatic events: impacts of drought and high temperature on physiological processes in agronomically important plants. Front Environ Sci. 2014;2 [Google Scholar]
46. Shi Y, Zhang Z, Yan Z. et al. Tomato mitogen-activated protein kinase: mechanisms of adaptation in response to biotic and abiotic stresses. Front Plant Sci. 2025;16:1533248. [DOI] [PMC free article] [PubMed] [Google Scholar]
47. Zhou Y, Singh SK, Patra B. et al. Mitogen-activated protein kinase-mediated regulation of plant specialized metabolism. J Exp Bot. 2025;76:262–76 [DOI] [PubMed] [Google Scholar]
48. Yang L, Zhang Y, Guan R. et al. Co-regulation of indole glucosinolates and camalexin biosynthesis by CPK5/CPK6 and MPK3/MPK6 signaling pathways. J Integr Plant Biol. 2020;62:1780–96 [DOI] [PMC free article] [PubMed] [Google Scholar]
49. Li Y, Cai H, Liu P. et al. Arabidopsis MAPKKK18 positively regulates drought stress resistance via downstream MAPKK3. Biochem Biophys Res Commun. 2017;484:292–7 [DOI] [PubMed] [Google Scholar]
50. Yu L, Nie J, Cao C. et al. Phosphatidic acid mediates salt stress response by regulation of MPK6 in Arabidopsis thaliana. New Phytol. 2010;188:762–73 [DOI] [PubMed] [Google Scholar]
51. Su S, Jiang Y, Zhu X. et al. Calcium-dependent protein kinases 5 and 13 enhance salt tolerance in rice by directly activating OsMPK3/6 kinases. Plant Physiol. 2024;196:3033–47 [DOI] [PMC free article] [PubMed] [Google Scholar]
52. Ren N, Zhang G, Yang X. et al. MAPKKK28 functions upstream of the MKK1-MPK1 cascade to regulate abscisic acid responses in rice. Plant, Cell & Environ. 2024;47:5140–57 [DOI] [PubMed] [Google Scholar]
53. Jia M, Luo N, Meng X. et al. OsMPK4 promotes phosphorylation and degradation of IPA1 in response to salt stress to confer salt tolerance in rice. J Genet Genomics. 2022;49:766–75 [DOI] [PubMed] [Google Scholar]
54. Tang W, Tang AY. Overexpression of Arabidopsis thaliana malonyl-CoA synthetase gene enhances cold stress tolerance by activating mitogen-activated protein kinases in plant cells. J For Res. 2020;32:741–53 [Google Scholar]
55. Zhao J, Zhu K, Chen M. et al. Identification and expression analysis of MPK and MKK gene families in pecan (Carya illinoinensis). Int J Mol Sci. 2022;23:15190. [DOI] [PMC free article] [PubMed] [Google Scholar]
56. Liu H, Li X, He F. et al. Genome-wide identification and analysis of abiotic stress responsiveness of the mitogen-activated protein kinase gene family in Medicago sativa L. BMC Plant Biol. 2024;24:800. [DOI] [PMC free article] [PubMed] [Google Scholar]
57. Wei C, Liu X, Long D. et al. Molecular cloning and expression analysis of mulberry MAPK gene family. Plant Physiol Biochem. 2014;77:108–16 [DOI] [PubMed] [Google Scholar]
58. Kumar K, Raina SK, Sultan SM. Arabidopsis MAPK signaling pathways and their cross talks in abiotic stress response. J Plant Biochem Biotechnol. 2020;29:700–14 [Google Scholar]
59. Li CH, Wang G, Zhao JL. et al. The receptor-like kinase SIT1 mediates salt sensitivity by activating MAPK3/6 and regulating ethylene homeostasis in rice. Plant Cell. 2014;26:2538–53 [DOI] [PMC free article] [PubMed] [Google Scholar]
60. Yao Y, Zhao H, Sun L. et al. Genome-wide identification of MAPK gene family members in Fagopyrum tataricum and their expression during development and stress responses. BMC Genomics. 2022;23:96. [DOI] [PMC free article] [PubMed] [Google Scholar]
61. Zhou HY, Ren SY, Han YF. et al. Identification and analysis of mitogen-activated protein kinase (MAPK) cascades in Fragaria vesca. Int J Mol Sci. 2017;18:1766. [DOI] [PMC free article] [PubMed] [Google Scholar]
62. Neupane S, Schweitzer SE, Neupane A. et al. Identification and characterization of mitogen-activated protein kinase (MAPK) genes in sunflower (Helianthus annuus L.). Plants. 2019;8:28. [DOI] [PMC free article] [PubMed] [Google Scholar]
63. Wang G, Wang T, Jia ZH. et al. Genome-wide bioinformatics analysis of MAPK gene family in kiwifruit (Actinidia Chinensis). Int J Mol Sci. 2018;19:2510. [DOI] [PMC free article] [PubMed] [Google Scholar]
64. Gao P, Xiao J, Guo W. et al. Genome-wide identification of Glycyrrhiza uralensis Fisch. MAPK gene family and expression analysis under salt stress relieved by Bacillus subtilis. Front Genet. 2024;15:1442277. [DOI] [PMC free article] [PubMed] [Google Scholar]
65. Sözen C, Schenk ST, Boudsocq M. et al. Wounding and insect feeding trigger two independent MAPK pathways with distinct regulation and kinetics. Plant Cell. 2020;32:1988–2003 [DOI] [PMC free article] [PubMed] [Google Scholar]
66. Matsuoka D, Soga K, Yasufuku T. et al. Control of plant growth and development by overexpressing MAP3K17, an ABA-inducible MAP3K, in Arabidopsis. Plant Biotechnol. 2018;35:171–6 [DOI] [PMC free article] [PubMed] [Google Scholar]
67. Umezawa T, Sugiyama N, Takahashi F. et al. Genetics and phosphoproteomics reveal a protein phosphorylation network in the abscisic acid signaling pathway in Arabidopsis thaliana. Sci Signal. 2013;6:rs8. [DOI] [PubMed] [Google Scholar]
68. Ma H, Chen J, Zhang Z. et al. MAPK kinase 10.2 promotes disease resistance and drought tolerance by activating different MAPKs in rice. Plant J. 2017;92:557–70 [DOI] [PubMed] [Google Scholar]
69. Alfagham AT, Debnath S, Perveen K. et al. Computational analysis of albaflavenone interaction with SlMAPK1 for drought resistance in tomato. Mol Biotechnol. 2024;67:2443–54 [DOI] [PubMed] [Google Scholar]
70. Virk N, Liu B, Zhang H. et al. Tomato SlMPK4 is required for resistance against botrytis cinerea and tolerance to drought stress. Acta Physiol Plant. 2012;35:1211–21 [Google Scholar]
71. Huang X, Wei J-M, Feng W-Z. et al. Interaction between SlMAPK3 and SlASR4 regulates drought resistance in tomato (Solanum lycopersicum L.). Mol Breed. 2023;43:73. [DOI] [PMC free article] [PubMed] [Google Scholar]
72. Dong W, Xie Q, Li J. et al. BpMAPK3-mediated BpWRKY53 phosphorylation enhances Betula platyphylla drought stress tolerance by increasing flavonoid content. Plant J. 2025;121:e70089 [DOI] [PubMed] [Google Scholar]
73. Huang XS, Luo T, Fu XZ. et al. Cloning and molecular characterization of a mitogen-activated protein kinase gene from Poncirus trifoliata whose ectopic expression confers dehydration/drought tolerance in transgenic tobacco. J Exp Bot. 2011;62:5191–206 [DOI] [PMC free article] [PubMed] [Google Scholar]
74. Weng CM, Lu JX, Wan HF. et al. Over-expression of BnMAPK1 in Brassica napus enhances tolerance to drought stress. J Integr Agric. 2014;13:2407–15 [Google Scholar]
75. Zhou Y, Bai YH, Han F-X. et al. Transcriptome sequencing and metabolome analysis reveal the molecular mechanism of Salvia miltiorrhiza in response to drought stress. BMC Plant Biol. 2024;24:446. [DOI] [PMC free article] [PubMed] [Google Scholar]
76. Zhou Y, Ma W, Bai Y. et al. The protein kinase SmSnRK2.7 mediates abscisic acid-regulated tanshinone biosynthesis under drought stress in Salvia miltiorrhiza. Ind Crop Prod. 2025;235:121605 [Google Scholar]
77. Jiang S, Li H, Zhang L. et al. Generic diagramming platform (GDP): a comprehensive database of high-quality biomedical graphics. Nucleic Acids Res. 2025;53:D1670–6 [DOI] [PMC free article] [PubMed] [Google Scholar]
78. Zhao S, Zhang Q, Liu M. et al. Regulation of plant responses to salt stress. Int J Mol Sci. 2021;22:4609. [DOI] [PMC free article] [PubMed] [Google Scholar]
79. Teige M, Scheikl E, Eulgem T. et al. The MKK2 pathway mediates cold and salt stress signaling in Arabidopsis. Mol Cell. 2004;15:141–52 [DOI] [PubMed] [Google Scholar]
80. Schmidt R, Mieulet D, Hubberten HM. et al. Salt-responsive ERF1 regulates reactive oxygen species-dependent signaling during the initial response to salt stress in rice. Plant Cell. 2013;25:2115–31 [DOI] [PMC free article] [PubMed] [Google Scholar]
81. Li J, Zhang C, Miao Y. et al. Mitogen-activated protein kinase 7 phosphorylates transcription factor ZmWRKY104 to enhance salt tolerance in maize. J Exp Bot. 2025;76:4709–25 [DOI] [PubMed] [Google Scholar]
82. Ding R, Li J, Wang J. et al. Molecular traits of MAPK kinases and the regulatory mechanism of GhMAPKK5 alleviating drought/salt stress in cotton. Plant Physiol. 2024;196:2030–47 [DOI] [PMC free article] [PubMed] [Google Scholar]
83. Wang C, Shan D, Bai Y. et al. MdMAPK3-driven phosphorylation enhances MdWRKY17-mediated regulation of high-affinity K⁺ transporter 1 MdHAK1 for salt tolerance in apple. Int J Biol Macromol. 2025;316:144633 [DOI] [PubMed] [Google Scholar]
84. Yin P, Wang H, Ye Z. et al. The ZmMPK3-ZmGRF1 module promotes maize growth by enhancing cell proliferation under salt stress. Sci Bull. 2025;S2095-9273(25)00669-3 [DOI] [PubMed] [Google Scholar]
85. Ji G, Lu Q, Yu Y. et al. Function identification of the mitogen-activated protein kinase gene CsMPK4 in cucumber. Chin J Biotechnol. 2025;41:857–68 [DOI] [PubMed] [Google Scholar]
86. Shi L, Shi W, Qiu Z. et al. CaMAPK1 plays a vital role in the regulation of resistance to Ralstonia solanacearum infection and tolerance to heat stress. Plants. 2024;13:1775. [DOI] [PMC free article] [PubMed] [Google Scholar]
87. Ding H, Wu Y, Yuan G. et al. In-depth proteome analysis reveals multiple pathways involved in tomato SlMPK1-mediated high-temperature responses. Protoplasma. 2020;257:43–59 [DOI] [PubMed] [Google Scholar]
88. Ding H, He J, Wu Y. et al. The tomato mitogen-activated protein kinase SlMPK1 is as a negative regulator of the high-temperature stress response. Plant Physiol. 2018;177:633–51 [DOI] [PMC free article] [PubMed] [Google Scholar]
89. Wang T, Liu M, Wu Y. et al. Genome-wide identification and expression analysis of MAPK gene family in lettuce (Lactuca sativa L.) and functional analysis of LsMAPK4 in high-temperature-induced bolting. Int J Mol Sci. 2022;23:11129. [DOI] [PMC free article] [PubMed] [Google Scholar]
90. Kim SH, Hussain S, Pham HTT. et al. Phosphorylation of auxin signaling repressor IAA8 by heat-responsive MPKs causes defective flower development. Plant Physiol. 2024;196:2825–40 [DOI] [PMC free article] [PubMed] [Google Scholar]
91. Li H, Ding Y, Shi Y. et al. MPK3- and MPK6-mediated ICE1 phosphorylation negatively regulates ICE1 stability and freezing tolerance in Arabidopsis. Dev Cell. 2017;43:630–642.e4 [DOI] [PubMed] [Google Scholar]
92. Zhao C, Wang P, Si T. et al. MAP kinase cascades regulate the cold response by modulating ICE1 protein stability. Dev Cell. 2017;43:618–629.e5 [DOI] [PMC free article] [PubMed] [Google Scholar]
93. Song J, Lin R, Tang M. et al. SlMPK1-and SlMPK2-mediated SlBBX17 phosphorylation positively regulates CBF-dependent cold tolerance in tomato. New Phytol. 2023;239:1887–902 [DOI] [PubMed] [Google Scholar]
94. Yu L, Yan J, Yang Y. et al. Enhanced tolerance to chilling stress in tomato by overexpression of a mitogen-activated protein kinase, SlMPK7. Plant Mol Biol Report. 2016;34:76–88 [Google Scholar]
95. Park SU, Jung YJ, Kwon HJ. et al. IbMPK3/IbMPK6-mediated IbSPF1 phosphorylation promotes cold stress tolerance in sweet potato. Biochem Biophys Res Commun. 2025;769:151893 [DOI] [PubMed] [Google Scholar]
96. Meraj TA, Fu J, Raza MA. et al. Transcriptional factors regulate plant stress responses through mediating secondary metabolism. Genes. 2020;11:346. [DOI] [PMC free article] [PubMed] [Google Scholar]
97. Xing Y, Sun W, Sun Y. et al. MPK6-mediated HY5 phosphorylation regulates light-induced anthocyanin accumulation in apple fruit. Plant Biotechnol J. 2022;21:283–301 [DOI] [PMC free article] [PubMed] [Google Scholar]
98. Wang S, Wang T, Li Q. et al. Phosphorylation of MdERF17 by MdMPK4 promotes apple fruit peel degreening during light/dark transitions. Plant Cell. 2022;34:1980–2000 [DOI] [PMC free article] [PubMed] [Google Scholar]
99. Mao W, Han Y, Chen Y. et al. Low temperature inhibits anthocyanin accumulation in strawberry fruit by activating FvMAPK3-induced phosphorylation of FvMYB10 and degradation of chalcone synthase 1. Plant Cell. 2022;34:1226–49 [DOI] [PMC free article] [PubMed] [Google Scholar]
100. Bai Y, Shi K, Shan D. et al. The WRKY17-WRKY50 complex modulates anthocyanin biosynthesis to improve drought tolerance in apple. Plant Sci. 2024;340:111965 [DOI] [PubMed] [Google Scholar]
101. Yang C, Zhang P, Jiang P. et al. GmMYB4 positively regulates isoflavone biosynthesis via the GmMAPK6-GmMYB4-MBW module in soybean. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]
102. Lin H, Chen Y, Nomura K. et al. An MKP-MAPK protein phosphorylation cascade controls vascular immunity in plants. Sci Adv. 2022;8:eabg8723. [DOI] [PMC free article] [PubMed] [Google Scholar]
103. Gui J, Luo L, Zhong Y. et al. Phosphorylation of LTF1, an MYB transcription factor in populus, acts as a sensory switch regulating lignin biosynthesis in wood cells. Mol Plant. 2019;12:1325–37 [DOI] [PubMed] [Google Scholar]
104. Yin X, Liu S, Zhang Y. et al. Rosmarinic acid synthase 1 phosphorylation by SmMAPK3 is required for salicylic acid-induced salvianolic acid accumulation in Salvia miltiorrhiza hairy roots. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]
105. Xie Y, Ding M, Yin X. et al. MAPKK2/4/5/7-MAPK3-JAZs modulate phenolic acid biosynthesis in Salvia miltiorrhiza. Phytochemistry. 2022;199:113177 [DOI] [PubMed] [Google Scholar]
106. Qu R, Wang S, Wang X. et al. The jasmonate-responsive SmMPK3–SmWRKY33 module positively regulates tanshinone biosynthesis in Salvia miltiorrhiza. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]
107. Tan X, Chen J, Zhang J. et al. Gene expression and interaction analysis of FsWRKY4 and FsMAPK3 in Forsythia suspensa. Plants. 2023;12:3415. [DOI] [PMC free article] [PubMed] [Google Scholar]
108. Xie Q, Dong W, Wang M. et al. BpWRKY6 regulates insect resistance by affecting jasmonic acid and terpenoid synthesis in Betula platyphylla. Plant Biotechnol J. 2025;23:3682–96 [DOI] [PMC free article] [PubMed] [Google Scholar]
109. Luo D, Wang T, Ye M. et al. Identification and characterization of Crocus sativus WRKY and its interacting MPK involved in crocins biosynthesis based on full-length transcriptome analysis. Ind Crop Prod. 2023;197:116559 [Google Scholar]
110. Li Z, Wang W, Li G. et al. MAPK-mediated regulation of growth and essential oil composition in a salt-tolerant peppermint (Mentha piperita L.) under NaCl stress. Protoplasma. 2015;253:1541–56 [DOI] [PubMed] [Google Scholar]
111. Ma J, Wei L, Huang K. et al. Biosynthesis of sakuranetin regulated by OsMPK6-OsWRKY67-OsNOMT cascade enhances resistance to false smut disease. New Phytol. 2024;245:1216–31 [DOI] [PubMed] [Google Scholar]
112. Lu L, Fang J, Xia N. et al. Phosphorylation of the transcription factor OsNAC29 by OsMAPK3 activates diterpenoid genes to promote rice immunity. Plant Cell. 2025;37:koae320. [DOI] [PMC free article] [PubMed] [Google Scholar]
113. Lin X, Ding C, Xiao W. et al. A molecular switch OsWRKY10-OsVQ8 orchestrates rice diterpenoid phytoalexin biosynthesis for broad-spectrum disease resistance. New Phytol. 2025;246:2243–62 [DOI] [PubMed] [Google Scholar]
114. Mao G, Meng X, Liu Y. et al. Phosphorylation of a WRKY transcription factor by two pathogen-responsive MAPKs drives phytoalexin biosynthesis in Arabidopsis. Plant Cell. 2011;23:1639–53 [DOI] [PMC free article] [PubMed] [Google Scholar]
115. Raina SK, Wankhede DP, Singh P. et al. CrMPK3, a mitogen activated protein kinase from Catharanthus roseus and its possible role in stress induced biosynthesis of monoterpenoid indole alkaloids. BMC Plant Biol. 2012;12:134. [DOI] [PMC free article] [PubMed] [Google Scholar]
116. Paul P, Singh SK, Patra B. et al. A differentially regulated AP2/ERF transcription factor gene cluster acts downstream of a MAP kinase cascade to modulate terpenoid indole alkaloid biosynthesis in Catharanthus roseus. New Phytol. 2017;213:1107–23 [DOI] [PubMed] [Google Scholar]
117. Liu X, Singh SK, Patra B. et al. Protein phosphatase NtPP2C2b and MAP kinase NtMPK4 act in concert to modulate nicotine biosynthesis. J Exp Bot. 2021;72:1661–76 [DOI] [PMC free article] [PubMed] [Google Scholar]
118. Zhou Y, Liu Y, Lyu R. et al. Post-translational control of biotic stress-related nicotine biosynthesis by a MAP kinase signaling cascade. Crop J. 2025 [Google Scholar]
119. Xie G, Kato H, Imai R. Biochemical identification of the OsMKK6–OsMPK3 signalling pathway for chilling stress tolerance in rice. Biochem J. 2012;443:95–102 [DOI] [PubMed] [Google Scholar]
120. Wang L, Zhao R, Li R. et al. Enhanced drought tolerance in tomato plants by overexpression of SlMAPK1. Plant Cell Tiss Org. 2018;133:27–38 [Google Scholar]
121. Zheng T, Li Y, Lei W. et al. SUMO E3 ligase SIZ1 stabilizes MYB75 to regulate anthocyanin accumulation under high light conditions in Arabidopsis. Plant Sci. 2020;292:110355 [DOI] [PubMed] [Google Scholar]
122. Maier A, Schrader A, Kokkelink L. et al. Light and the E3 ubiquitin ligase COP 1/SPA control the protein stability of the MYB transcription factors PAP 1 and PAP 2 involved in anthocyanin accumulation in Arabidopsis. Plant J. 2013;74:638–51 [DOI] [PubMed] [Google Scholar]
123. Friso G, Wijk KJV. Post-translational protein modifications in plant metabolism. Plant Physiol. 2015;169:01378.2015–87 [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Web_Material_uhaf350

web_material_uhaf350.zip^{(83.8KB, zip)}

[ref1] 1. Mofokeng MM, Du Plooy CP, Araya HT. et al. Medicinal plant cultivation for sustainable use and commercialisation of high-value crops. S Afr J Sci. 2022;118:1–7 [Google Scholar]

[ref2] 2. Alami MM, Guo S, Mei Z. et al. Environmental factors on secondary metabolism in medicinal plants: exploring accelerating factors. Med Plant Biol. 2024;3:e016 [Google Scholar]

[ref3] 3. Tang H, Wang Q, Xie H. et al. The function of secondary metabolites in resisting stresses in horticultural plants. Fruit Res. 2024;4:e021 [Google Scholar]

[ref4] 4. Rabeh K, Hnini M, Oubohssaine M. A comprehensive review of transcription factor-mediated regulation of secondary metabolites in plants under environmental stress. Stress Biol. 2025;5:15 [Google Scholar]

[ref5] 5. Anzano A, Bonanomi G, Mazzoleni S. et al. Plant metabolomics in biotic and abiotic stress: a critical overview. Phytochem Rev. 2022;21:503–24 [Google Scholar]

[ref6] 6. Haak DC, Fukao T, Grene R. et al. Multilevel regulation of abiotic stress responses in plants. Front Plant Sci. 2017;8:1564. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref7] 7. Hanaka A, Majewska M, Jaroszuk-Ściseł J. Study of the influence of abiotic and biotic stress factors on horticultural plants. Horticulturae. 2021;8:6 [Google Scholar]

[ref8] 8. Chen X, Ding Y, Yang Y. et al. Protein kinases in plant responses to drought, salt, and cold stress. J Integr Plant Biol. 2021;63:53–78 [DOI] [PubMed] [Google Scholar]

[ref9] 9. Del Río LA. ROS and RNS in plant physiology: an overview. J Exp Bot. 2015;66:2827–37 [DOI] [PubMed] [Google Scholar]

[ref10] 10. Dong Q, Wallrad L, Almutairi BO. et al. Ca²⁺ signaling in plant responses to abiotic stresses. J Integr Plant Biol. 2022;64:287–300 [DOI] [PubMed] [Google Scholar]

[ref11] 11. Zhu JK. Abiotic stress signaling and responses in plants. Cell. 2016;167:313–24 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref12] 12. Liu S, Zhang Q, Kolli L. et al. Molecular networks of secondary metabolism accumulation in plants: current understanding and future challenges. Ind Crop Prod. 2023;201:116901 [Google Scholar]

[ref13] 13. Isah T. Stress and defense responses in plant secondary metabolites production. Biol Res. 2019;52:39. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref14] 14. Upadhyay AL, Lambat P, Borthakur M. Secondary metabolite production in plants: in response to biotic and abiotic stress factors. J Adv Zool. 2024;45:55–9 [Google Scholar]

[ref15] 15. Silva-Sanchez C, Li H, Chen S. Recent advances and challenges in plant phosphoproteomics. Proteomics. 2015;15:1127–41 [DOI] [PubMed] [Google Scholar]

[ref16] 16. Bigeard J, Hirt H. Nuclear signaling of plant MAPKs. Front Plant Sci. 2018;9:469. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref17] 17. Mohanta TK, Arora PK, Mohanta N. et al. Identification of new members of the MAPK gene family in plants shows diverse conserved domains and novel activation loop variants. BMC Genomics. 2015;16:58. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref18] 18. Cristina MS, Petersen M, Mundy J. Mitogen-activated protein kinase signaling in plants. Annu Rev Plant Biol. 2010;61:621–49 [DOI] [PubMed] [Google Scholar]

[ref19] 19. Li H, Chen N, Zhang H. et al. Multidimensional regulation of transcription factors: decoding the comprehensive signals of plant secondary metabolism. Front Plant Sci. 2025;16:1522278. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref20] 20. Zhang M, Su J, Zhang Y. et al. Conveying endogenous and exogenous signals: MAPK cascades in plant growth and defense. Curr Opin Plant Biol. 2018;45:1–10 [DOI] [PubMed] [Google Scholar]

[ref21] 21. Xu J, Zhang S. Mitogen-activated protein kinase cascades in signaling plant growth and development. Trends Plant Sci. 2015;20:56–64 [DOI] [PubMed] [Google Scholar]

[ref22] 22. Dong G, Gui Z, Yuan Y. et al. Expression analysis of the extensive regulation of mitogen-activated protein kinase (MAPK) family genes in buckwheat (Fagopyrum tataricum) during organ differentiation and stress response. Agronomy. 2024;14:2613 [Google Scholar]

[ref23] 23. You X, Fan N, Zhang Y. et al. The MsNAC73–MsMPK3 complex modulates salt tolerance and shoot branching of alfalfa via activating MsPG2 and MsPAE12 expressions. Plant Biotechnol J. 2025;23:5635–53 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref24] 24. Zhang Z, Liu H, Sun C. et al. A C2H2 zinc-finger protein OsZFP213 interacts with OsMAPK3 to enhance salt tolerance in rice. J Plant Physiol. 2018;229:100–10 [DOI] [PubMed] [Google Scholar]

[ref25] 25. Kishi-Kaboshi M, Okada K, Kurimoto L. et al. A rice fungal MAMP-responsive MAPK cascade regulates metabolic flow to antimicrobial metabolite synthesis. Plant J. 2010;63:599–612 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref26] 26. Colcombet J, Hirt H. Arabidopsis MAPKs: a complex signalling network involved in multiple biological processes. Biochem J. 2008;413:217–26 [DOI] [PubMed] [Google Scholar]

[ref27] 27. Lei L, Li Y, Wang Q. et al. Activation of MKK9-MPK3/MPK6 enhances phosphate acquisition in Arabidopsis thaliana. New Phytol. 2014;203:1146–60 [DOI] [PubMed] [Google Scholar]

[ref28] 28. Danquah A, de Zélicourt A, Boudsocq M. et al. Identification and characterization of an ABA-activated MAP kinase cascade in Arabidopsis thaliana. Plant J. 2015;82:232–44 [DOI] [PubMed] [Google Scholar]

[ref29] 29. Li S, Wang W, Gao J. et al. MYB75 phosphorylation by MPK4 is required for light-induced anthocyanin accumulation in Arabidopsis. Plant Cell. 2016;28:2866–83 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref30] 30. Luo J, Wang X, Feng L. et al. The mitogen-activated protein kinase kinase 9 (MKK9) modulates nitrogen acquisition and anthocyanin accumulation under nitrogen-limiting condition in Arabidopsis. Biochem Biophys Res Commun. 2017;487:539–44 [DOI] [PubMed] [Google Scholar]

[ref31] 31. Rohila JS, Yang Y. Rice mitogen-activated protein kinase gene family and its role in biotic and abiotic stress response. J Integr Plant Biol. 2007;49:751–9 [Google Scholar]

[ref32] 32. Chen J, Wang L, Yuan M. Update on the roles of rice MAPK cascades. Int J Mol Sci. 2021;22:1679. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref33] 33. Zhang Z, Li J, Li F. et al. OsMAPK3 phosphorylates OsbHLH002/OsICE1 and inhibits its ubiquitination to activate OsTPP1 and enhances rice chilling tolerance. Dev Cell. 2017;43:731–743.e5 [DOI] [PubMed] [Google Scholar]

[ref34] 34. Wang L, Xu J, Li L. et al. The OsBDR1-MPK3 module negatively regulates blast resistance by suppressing the jasmonate signaling and terpenoid biosynthesis pathway. Proc Natl Acad Sci USA. 2023;120:e2211102120 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref35] 35. Ye T, Wang H, Zhang L. et al. A novel OsCRK14–OsRLCK57–MAPK signaling module activates OsbZIP66 to confer drought resistance in rice. Mol Plant. 2025;18:1390–408 [DOI] [PubMed] [Google Scholar]

[ref36] 36. Wang F, Jing W, Zhang W. The mitogen-activated protein kinase cascade MKK1–MPK4 mediates salt signaling in rice. Plant Sci. 2014;227:181–9 [DOI] [PubMed] [Google Scholar]

[ref37] 37. Zhang C, Zhu Z, Jiang A. et al. Genome-wide identification of the mitogen-activated kinase gene family from Limonium bicolor and functional characterization of LbMAPK2 under salt stress. BMC Plant Biol. 2023;23:565. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref38] 38. Liao J, Dong Y, Hua Z. et al. Identification of eggplant SmMPK gene family and functional verification of SmMPK4.1. Horticulturae. 2024;10:239 [Google Scholar]

[ref39] 39. Tamura K, Stecher G, Kumar S. et al. MEGA11: molecular evolutionary genetics analysis version 11. Mol Biol Evol. 2021;38:3022–7 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref40] 40. Song A, Hu Y, Ding L. et al. Comprehensive analysis of mitogen-activated protein kinase cascades in chrysanthemum. Peer J. 2018;6:e5037 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref41] 41. Zhang S, Xu R, Luo X. et al. Genome-wide identification and expression analysis of MAPK and MAPKK gene family in Malus domestica. Gene. 2013;531:377–87 [DOI] [PubMed] [Google Scholar]

[ref42] 42. Xie Y, Ding M, Zhang B. et al. Genome-wide characterization and expression profiling of MAPK cascade genes in Salvia miltiorrhiza reveals the function of SmMAPK3 and SmMAPK1 in secondary metabolism. BMC Genomics. 2020;21:630. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref43] 43. Kong F, Wang J, Cheng L. et al. Genome-wide analysis of the mitogen-activated protein kinase gene family in Solanum lycopersicum. Gene. 2012;499:108–20 [DOI] [PubMed] [Google Scholar]

[ref44] 44. Çakır B, Kılıçkaya O. Mitogen-activated protein kinase cascades in Vitis vinifera. Front Plant Sci. 2015;6:556. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref45] 45. Feller U, Vaseva II. Extreme climatic events: impacts of drought and high temperature on physiological processes in agronomically important plants. Front Environ Sci. 2014;2 [Google Scholar]

[ref46] 46. Shi Y, Zhang Z, Yan Z. et al. Tomato mitogen-activated protein kinase: mechanisms of adaptation in response to biotic and abiotic stresses. Front Plant Sci. 2025;16:1533248. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref47] 47. Zhou Y, Singh SK, Patra B. et al. Mitogen-activated protein kinase-mediated regulation of plant specialized metabolism. J Exp Bot. 2025;76:262–76 [DOI] [PubMed] [Google Scholar]

[ref48] 48. Yang L, Zhang Y, Guan R. et al. Co-regulation of indole glucosinolates and camalexin biosynthesis by CPK5/CPK6 and MPK3/MPK6 signaling pathways. J Integr Plant Biol. 2020;62:1780–96 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref49] 49. Li Y, Cai H, Liu P. et al. Arabidopsis MAPKKK18 positively regulates drought stress resistance via downstream MAPKK3. Biochem Biophys Res Commun. 2017;484:292–7 [DOI] [PubMed] [Google Scholar]

[ref50] 50. Yu L, Nie J, Cao C. et al. Phosphatidic acid mediates salt stress response by regulation of MPK6 in Arabidopsis thaliana. New Phytol. 2010;188:762–73 [DOI] [PubMed] [Google Scholar]

[ref51] 51. Su S, Jiang Y, Zhu X. et al. Calcium-dependent protein kinases 5 and 13 enhance salt tolerance in rice by directly activating OsMPK3/6 kinases. Plant Physiol. 2024;196:3033–47 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref52] 52. Ren N, Zhang G, Yang X. et al. MAPKKK28 functions upstream of the MKK1-MPK1 cascade to regulate abscisic acid responses in rice. Plant, Cell & Environ. 2024;47:5140–57 [DOI] [PubMed] [Google Scholar]

[ref53] 53. Jia M, Luo N, Meng X. et al. OsMPK4 promotes phosphorylation and degradation of IPA1 in response to salt stress to confer salt tolerance in rice. J Genet Genomics. 2022;49:766–75 [DOI] [PubMed] [Google Scholar]

[ref54] 54. Tang W, Tang AY. Overexpression of Arabidopsis thaliana malonyl-CoA synthetase gene enhances cold stress tolerance by activating mitogen-activated protein kinases in plant cells. J For Res. 2020;32:741–53 [Google Scholar]

[ref55] 55. Zhao J, Zhu K, Chen M. et al. Identification and expression analysis of MPK and MKK gene families in pecan (Carya illinoinensis). Int J Mol Sci. 2022;23:15190. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref56] 56. Liu H, Li X, He F. et al. Genome-wide identification and analysis of abiotic stress responsiveness of the mitogen-activated protein kinase gene family in Medicago sativa L. BMC Plant Biol. 2024;24:800. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref57] 57. Wei C, Liu X, Long D. et al. Molecular cloning and expression analysis of mulberry MAPK gene family. Plant Physiol Biochem. 2014;77:108–16 [DOI] [PubMed] [Google Scholar]

[ref58] 58. Kumar K, Raina SK, Sultan SM. Arabidopsis MAPK signaling pathways and their cross talks in abiotic stress response. J Plant Biochem Biotechnol. 2020;29:700–14 [Google Scholar]

[ref59] 59. Li CH, Wang G, Zhao JL. et al. The receptor-like kinase SIT1 mediates salt sensitivity by activating MAPK3/6 and regulating ethylene homeostasis in rice. Plant Cell. 2014;26:2538–53 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref60] 60. Yao Y, Zhao H, Sun L. et al. Genome-wide identification of MAPK gene family members in Fagopyrum tataricum and their expression during development and stress responses. BMC Genomics. 2022;23:96. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref61] 61. Zhou HY, Ren SY, Han YF. et al. Identification and analysis of mitogen-activated protein kinase (MAPK) cascades in Fragaria vesca. Int J Mol Sci. 2017;18:1766. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref62] 62. Neupane S, Schweitzer SE, Neupane A. et al. Identification and characterization of mitogen-activated protein kinase (MAPK) genes in sunflower (Helianthus annuus L.). Plants. 2019;8:28. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref63] 63. Wang G, Wang T, Jia ZH. et al. Genome-wide bioinformatics analysis of MAPK gene family in kiwifruit (Actinidia Chinensis). Int J Mol Sci. 2018;19:2510. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref64] 64. Gao P, Xiao J, Guo W. et al. Genome-wide identification of Glycyrrhiza uralensis Fisch. MAPK gene family and expression analysis under salt stress relieved by Bacillus subtilis. Front Genet. 2024;15:1442277. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref65] 65. Sözen C, Schenk ST, Boudsocq M. et al. Wounding and insect feeding trigger two independent MAPK pathways with distinct regulation and kinetics. Plant Cell. 2020;32:1988–2003 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref66] 66. Matsuoka D, Soga K, Yasufuku T. et al. Control of plant growth and development by overexpressing MAP3K17, an ABA-inducible MAP3K, in Arabidopsis. Plant Biotechnol. 2018;35:171–6 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref67] 67. Umezawa T, Sugiyama N, Takahashi F. et al. Genetics and phosphoproteomics reveal a protein phosphorylation network in the abscisic acid signaling pathway in Arabidopsis thaliana. Sci Signal. 2013;6:rs8. [DOI] [PubMed] [Google Scholar]

[ref68] 68. Ma H, Chen J, Zhang Z. et al. MAPK kinase 10.2 promotes disease resistance and drought tolerance by activating different MAPKs in rice. Plant J. 2017;92:557–70 [DOI] [PubMed] [Google Scholar]

[ref69] 69. Alfagham AT, Debnath S, Perveen K. et al. Computational analysis of albaflavenone interaction with SlMAPK1 for drought resistance in tomato. Mol Biotechnol. 2024;67:2443–54 [DOI] [PubMed] [Google Scholar]

[ref70] 70. Virk N, Liu B, Zhang H. et al. Tomato SlMPK4 is required for resistance against botrytis cinerea and tolerance to drought stress. Acta Physiol Plant. 2012;35:1211–21 [Google Scholar]

[ref71] 71. Huang X, Wei J-M, Feng W-Z. et al. Interaction between SlMAPK3 and SlASR4 regulates drought resistance in tomato (Solanum lycopersicum L.). Mol Breed. 2023;43:73. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref72] 72. Dong W, Xie Q, Li J. et al. BpMAPK3-mediated BpWRKY53 phosphorylation enhances Betula platyphylla drought stress tolerance by increasing flavonoid content. Plant J. 2025;121:e70089 [DOI] [PubMed] [Google Scholar]

[ref73] 73. Huang XS, Luo T, Fu XZ. et al. Cloning and molecular characterization of a mitogen-activated protein kinase gene from Poncirus trifoliata whose ectopic expression confers dehydration/drought tolerance in transgenic tobacco. J Exp Bot. 2011;62:5191–206 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref74] 74. Weng CM, Lu JX, Wan HF. et al. Over-expression of BnMAPK1 in Brassica napus enhances tolerance to drought stress. J Integr Agric. 2014;13:2407–15 [Google Scholar]

[ref75] 75. Zhou Y, Bai YH, Han F-X. et al. Transcriptome sequencing and metabolome analysis reveal the molecular mechanism of Salvia miltiorrhiza in response to drought stress. BMC Plant Biol. 2024;24:446. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref76] 76. Zhou Y, Ma W, Bai Y. et al. The protein kinase SmSnRK2.7 mediates abscisic acid-regulated tanshinone biosynthesis under drought stress in Salvia miltiorrhiza. Ind Crop Prod. 2025;235:121605 [Google Scholar]

[ref77] 77. Jiang S, Li H, Zhang L. et al. Generic diagramming platform (GDP): a comprehensive database of high-quality biomedical graphics. Nucleic Acids Res. 2025;53:D1670–6 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref78] 78. Zhao S, Zhang Q, Liu M. et al. Regulation of plant responses to salt stress. Int J Mol Sci. 2021;22:4609. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref79] 79. Teige M, Scheikl E, Eulgem T. et al. The MKK2 pathway mediates cold and salt stress signaling in Arabidopsis. Mol Cell. 2004;15:141–52 [DOI] [PubMed] [Google Scholar]

[ref80] 80. Schmidt R, Mieulet D, Hubberten HM. et al. Salt-responsive ERF1 regulates reactive oxygen species-dependent signaling during the initial response to salt stress in rice. Plant Cell. 2013;25:2115–31 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref81] 81. Li J, Zhang C, Miao Y. et al. Mitogen-activated protein kinase 7 phosphorylates transcription factor ZmWRKY104 to enhance salt tolerance in maize. J Exp Bot. 2025;76:4709–25 [DOI] [PubMed] [Google Scholar]

[ref82] 82. Ding R, Li J, Wang J. et al. Molecular traits of MAPK kinases and the regulatory mechanism of GhMAPKK5 alleviating drought/salt stress in cotton. Plant Physiol. 2024;196:2030–47 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref83] 83. Wang C, Shan D, Bai Y. et al. MdMAPK3-driven phosphorylation enhances MdWRKY17-mediated regulation of high-affinity K⁺ transporter 1 MdHAK1 for salt tolerance in apple. Int J Biol Macromol. 2025;316:144633 [DOI] [PubMed] [Google Scholar]

[ref84] 84. Yin P, Wang H, Ye Z. et al. The ZmMPK3-ZmGRF1 module promotes maize growth by enhancing cell proliferation under salt stress. Sci Bull. 2025;S2095-9273(25)00669-3 [DOI] [PubMed] [Google Scholar]

[ref85] 85. Ji G, Lu Q, Yu Y. et al. Function identification of the mitogen-activated protein kinase gene CsMPK4 in cucumber. Chin J Biotechnol. 2025;41:857–68 [DOI] [PubMed] [Google Scholar]

[ref86] 86. Shi L, Shi W, Qiu Z. et al. CaMAPK1 plays a vital role in the regulation of resistance to Ralstonia solanacearum infection and tolerance to heat stress. Plants. 2024;13:1775. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref87] 87. Ding H, Wu Y, Yuan G. et al. In-depth proteome analysis reveals multiple pathways involved in tomato SlMPK1-mediated high-temperature responses. Protoplasma. 2020;257:43–59 [DOI] [PubMed] [Google Scholar]

[ref88] 88. Ding H, He J, Wu Y. et al. The tomato mitogen-activated protein kinase SlMPK1 is as a negative regulator of the high-temperature stress response. Plant Physiol. 2018;177:633–51 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref89] 89. Wang T, Liu M, Wu Y. et al. Genome-wide identification and expression analysis of MAPK gene family in lettuce (Lactuca sativa L.) and functional analysis of LsMAPK4 in high-temperature-induced bolting. Int J Mol Sci. 2022;23:11129. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref90] 90. Kim SH, Hussain S, Pham HTT. et al. Phosphorylation of auxin signaling repressor IAA8 by heat-responsive MPKs causes defective flower development. Plant Physiol. 2024;196:2825–40 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref91] 91. Li H, Ding Y, Shi Y. et al. MPK3- and MPK6-mediated ICE1 phosphorylation negatively regulates ICE1 stability and freezing tolerance in Arabidopsis. Dev Cell. 2017;43:630–642.e4 [DOI] [PubMed] [Google Scholar]

[ref92] 92. Zhao C, Wang P, Si T. et al. MAP kinase cascades regulate the cold response by modulating ICE1 protein stability. Dev Cell. 2017;43:618–629.e5 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref93] 93. Song J, Lin R, Tang M. et al. SlMPK1-and SlMPK2-mediated SlBBX17 phosphorylation positively regulates CBF-dependent cold tolerance in tomato. New Phytol. 2023;239:1887–902 [DOI] [PubMed] [Google Scholar]

[ref94] 94. Yu L, Yan J, Yang Y. et al. Enhanced tolerance to chilling stress in tomato by overexpression of a mitogen-activated protein kinase, SlMPK7. Plant Mol Biol Report. 2016;34:76–88 [Google Scholar]

[ref95] 95. Park SU, Jung YJ, Kwon HJ. et al. IbMPK3/IbMPK6-mediated IbSPF1 phosphorylation promotes cold stress tolerance in sweet potato. Biochem Biophys Res Commun. 2025;769:151893 [DOI] [PubMed] [Google Scholar]

[ref96] 96. Meraj TA, Fu J, Raza MA. et al. Transcriptional factors regulate plant stress responses through mediating secondary metabolism. Genes. 2020;11:346. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref97] 97. Xing Y, Sun W, Sun Y. et al. MPK6-mediated HY5 phosphorylation regulates light-induced anthocyanin accumulation in apple fruit. Plant Biotechnol J. 2022;21:283–301 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref98] 98. Wang S, Wang T, Li Q. et al. Phosphorylation of MdERF17 by MdMPK4 promotes apple fruit peel degreening during light/dark transitions. Plant Cell. 2022;34:1980–2000 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref99] 99. Mao W, Han Y, Chen Y. et al. Low temperature inhibits anthocyanin accumulation in strawberry fruit by activating FvMAPK3-induced phosphorylation of FvMYB10 and degradation of chalcone synthase 1. Plant Cell. 2022;34:1226–49 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref100] 100. Bai Y, Shi K, Shan D. et al. The WRKY17-WRKY50 complex modulates anthocyanin biosynthesis to improve drought tolerance in apple. Plant Sci. 2024;340:111965 [DOI] [PubMed] [Google Scholar]

[ref101] 101. Yang C, Zhang P, Jiang P. et al. GmMYB4 positively regulates isoflavone biosynthesis via the GmMAPK6-GmMYB4-MBW module in soybean. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref102] 102. Lin H, Chen Y, Nomura K. et al. An MKP-MAPK protein phosphorylation cascade controls vascular immunity in plants. Sci Adv. 2022;8:eabg8723. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref103] 103. Gui J, Luo L, Zhong Y. et al. Phosphorylation of LTF1, an MYB transcription factor in populus, acts as a sensory switch regulating lignin biosynthesis in wood cells. Mol Plant. 2019;12:1325–37 [DOI] [PubMed] [Google Scholar]

[ref104] 104. Yin X, Liu S, Zhang Y. et al. Rosmarinic acid synthase 1 phosphorylation by SmMAPK3 is required for salicylic acid-induced salvianolic acid accumulation in Salvia miltiorrhiza hairy roots. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref105] 105. Xie Y, Ding M, Yin X. et al. MAPKK2/4/5/7-MAPK3-JAZs modulate phenolic acid biosynthesis in Salvia miltiorrhiza. Phytochemistry. 2022;199:113177 [DOI] [PubMed] [Google Scholar]

[ref106] 106. Qu R, Wang S, Wang X. et al. The jasmonate-responsive SmMPK3–SmWRKY33 module positively regulates tanshinone biosynthesis in Salvia miltiorrhiza. Plant Biotechnol J. 2025 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref107] 107. Tan X, Chen J, Zhang J. et al. Gene expression and interaction analysis of FsWRKY4 and FsMAPK3 in Forsythia suspensa. Plants. 2023;12:3415. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref108] 108. Xie Q, Dong W, Wang M. et al. BpWRKY6 regulates insect resistance by affecting jasmonic acid and terpenoid synthesis in Betula platyphylla. Plant Biotechnol J. 2025;23:3682–96 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref109] 109. Luo D, Wang T, Ye M. et al. Identification and characterization of Crocus sativus WRKY and its interacting MPK involved in crocins biosynthesis based on full-length transcriptome analysis. Ind Crop Prod. 2023;197:116559 [Google Scholar]

[ref110] 110. Li Z, Wang W, Li G. et al. MAPK-mediated regulation of growth and essential oil composition in a salt-tolerant peppermint (Mentha piperita L.) under NaCl stress. Protoplasma. 2015;253:1541–56 [DOI] [PubMed] [Google Scholar]

[ref111] 111. Ma J, Wei L, Huang K. et al. Biosynthesis of sakuranetin regulated by OsMPK6-OsWRKY67-OsNOMT cascade enhances resistance to false smut disease. New Phytol. 2024;245:1216–31 [DOI] [PubMed] [Google Scholar]

[ref112] 112. Lu L, Fang J, Xia N. et al. Phosphorylation of the transcription factor OsNAC29 by OsMAPK3 activates diterpenoid genes to promote rice immunity. Plant Cell. 2025;37:koae320. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref113] 113. Lin X, Ding C, Xiao W. et al. A molecular switch OsWRKY10-OsVQ8 orchestrates rice diterpenoid phytoalexin biosynthesis for broad-spectrum disease resistance. New Phytol. 2025;246:2243–62 [DOI] [PubMed] [Google Scholar]

[ref114] 114. Mao G, Meng X, Liu Y. et al. Phosphorylation of a WRKY transcription factor by two pathogen-responsive MAPKs drives phytoalexin biosynthesis in Arabidopsis. Plant Cell. 2011;23:1639–53 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref115] 115. Raina SK, Wankhede DP, Singh P. et al. CrMPK3, a mitogen activated protein kinase from Catharanthus roseus and its possible role in stress induced biosynthesis of monoterpenoid indole alkaloids. BMC Plant Biol. 2012;12:134. [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref116] 116. Paul P, Singh SK, Patra B. et al. A differentially regulated AP2/ERF transcription factor gene cluster acts downstream of a MAP kinase cascade to modulate terpenoid indole alkaloid biosynthesis in Catharanthus roseus. New Phytol. 2017;213:1107–23 [DOI] [PubMed] [Google Scholar]

[ref117] 117. Liu X, Singh SK, Patra B. et al. Protein phosphatase NtPP2C2b and MAP kinase NtMPK4 act in concert to modulate nicotine biosynthesis. J Exp Bot. 2021;72:1661–76 [DOI] [PMC free article] [PubMed] [Google Scholar]

[ref118] 118. Zhou Y, Liu Y, Lyu R. et al. Post-translational control of biotic stress-related nicotine biosynthesis by a MAP kinase signaling cascade. Crop J. 2025 [Google Scholar]

[ref119] 119. Xie G, Kato H, Imai R. Biochemical identification of the OsMKK6–OsMPK3 signalling pathway for chilling stress tolerance in rice. Biochem J. 2012;443:95–102 [DOI] [PubMed] [Google Scholar]

[ref120] 120. Wang L, Zhao R, Li R. et al. Enhanced drought tolerance in tomato plants by overexpression of SlMAPK1. Plant Cell Tiss Org. 2018;133:27–38 [Google Scholar]

[ref121] 121. Zheng T, Li Y, Lei W. et al. SUMO E3 ligase SIZ1 stabilizes MYB75 to regulate anthocyanin accumulation under high light conditions in Arabidopsis. Plant Sci. 2020;292:110355 [DOI] [PubMed] [Google Scholar]

[ref122] 122. Maier A, Schrader A, Kokkelink L. et al. Light and the E3 ubiquitin ligase COP 1/SPA control the protein stability of the MYB transcription factors PAP 1 and PAP 2 involved in anthocyanin accumulation in Arabidopsis. Plant J. 2013;74:638–51 [DOI] [PubMed] [Google Scholar]

[ref123] 123. Friso G, Wijk KJV. Post-translational protein modifications in plant metabolism. Plant Physiol. 2015;169:01378.2015–87 [DOI] [PMC free article] [PubMed] [Google Scholar]

PERMALINK

MAPK regulates secondary metabolism and abiotic stress in horticultural and medicinal plants

Shuanglu Liu

Minghui Xing

Xiaojian Yin

Abstract

Introduction

Table 2.

Table 3.

Table 4.

Composition, classification, and phylogenetic relationships of MAPKs in model, horticultural, and medicinal plants

Table 1.

Figure 1.

The response, function, and regulatory network of MAPK in abiotic stress

MAPKs involved in abiotic stress response

MAPK-mediated regulation of phytohormone signaling and ROS homeostasis enhances plant drought tolerance

Figure 2.

MAPK-mediated regulation of phytohormone signaling, ion homeostasis, and ROS detoxification enhances plant salt tolerance

Figure 3.

MAPK-mediated coordination of heat and cold signaling networks enhances plant thermotolerance

Figure 4.

MAPK regulates secondary metabolite biosynthesis

Pigmentation and quality-related metabolites in horticultural plants

Figure 5.

Bioactive metabolites in medicinal plants

Figure 6.

Defensive metabolites

Figure 7.

Conclusions

Perspectives

Supplementary Material

Acknowledgments

Contributor Information

Author contributions

Conflicts of interest statement

Supplementary material

References

Associated Data

Supplementary Materials

ACTIONS

PERMALINK

RESOURCES

Similar articles

Cited by other articles

Links to NCBI Databases