Fig. 4.

Epitranscriptome-mediated RNA metabolism and its effects on plant development, cellular processes, and stress responses. a OsEDM2L mediates m⁶A modification of OsEAT1, resulting in proper alternative splicing of OsEAT1 in rice anther development. b m⁶A modification affects alternative polyadenylation (APA) in Arabidopsis. Binding of CPSF30L to m⁶A-modified SOC1 mRNA regulates its APA and results in relatively stable SOC1 transcripts with a shorter 3′UTR to promote flowering. CPSF30L also mediates nitrate signaling through regulating the APA of several m⁶A-modified transcripts, including NRT1.1 and WRKY1, in the nitrate signaling pathway. VIR mediates m⁶A modification and APA of several stress-related transcripts in salt stress response. c m⁶A deposition on salt-stress-responsive transcripts by MTA is associated with a decrease in RNA secondary structures, causing increased RNA stability. d m⁶A modification affects protein translation in several crops. In strawberry fruit ripening, FveMTA- and FveMTB-mediated m⁶A modification of ABAR facilitates its translation. In apple, binding of MhYTP2 to m⁶A-modified MdGDH1L promotes its translation to confer powdery mildew resistance. In rice, OsNSUN2-dependent m⁵C modification increased protein synthesis to enhance rice adaptation to heat stress. e m⁵C RNA modification regulates RNA transport over the grafting junction in Arabidopsis. f m⁶A modification affects RNA stability in various plants. In Arabidopsis, m⁶A modification of WUS and STM mediated by FIP37 and MTA reduces their mRNA stability to maintain normal stem cell activity. The m⁶A eraser ALKBH10B demethylates FT, SPL3, and SPL9, thus enhancing their mRNA stability to promote flowering in Arabidopsis. In rice, OsFIP37 interacts with OsFAP1 to deposit m⁶A modification on OsYUCCA3 transcripts to promote auxin biosynthesis required for male meiosis. In tomato fruits, SlALKBH2 demethylates and enhances the stability of SlDML2 to accelerate fruit ripening. In strawberry, FveMTA and FveMTB deposit m⁶A modification on NCED5 and AREB1 transcripts, thus enhancing their RNA stability to promote fruit ripening. In apple, MhYTP2 binding to m⁶A-modified transcripts of MdMLO19 and MdMLO19-X1 destabilizes their transcripts to promote resistance to powdery mildew. g TRM4B-dependent m⁵C modification enhances RNA stability of its target transcripts in Arabidopsis root development. Created with Biorender.com