Table 1.
List of miRNAs along with their target function during heavy metal toxicity tolerance.
| miRNA | Plant Species | Stress | Target Genes | Target Function | Reference |
|---|---|---|---|---|---|
| miR156 |
A. thaliana, V. Vinifera, O. sativa, Nicotiana tabacum L., Miscanthus sinensis A. |
Cu, Cd, Cr, Al | SPL7 | Regulate Cu homeostasis, decrease endogenous ROS | [32,33,34,35,36,37] |
| miR159 | Brassica napus L., O. sativa, N. tabacum, M. truncatula, Saccharum spp | Cd, As, Cr, Al | ABC transporter protein, OPT1 | Regulate metal transporters | [35,36,38,39,40,41] |
| miR160 | A. thaliana, O. sativa, Saccharum spp | Cr, Al | ARF | Regulate auxin signal | [41,42] |
| miR164 |
A. thaliana, O. sativa, M. sinensis,
Saccharum spp |
As, Cr, Al, Hg | NAC, CUP trancription factors | Signaling pathway, root development, response to oxidative stress | [41,43,44] |
| miR166 | O. sativa, N. tabacum | Cd, Cr | Homeodomain containing protein 4 | Reduced Cd translocation from roots to shoots and Cd accumulation in seeds, decrease Cd-induced oxidative stress | [35,36,45] |
| miR167 | O. sativa, B. juncea, N. tabacum | Cd, As | NRAMP1b metal transporter protein | Metal uptake and translocation | [36,46,47] |
| miR168 | O. sativa, | Cd | LOX1 | Promote JA synthesis | [48] |
| miR169 | M. truncatula, O. satva, N. tabaccum, B. juncea | Cr, Cd, Al, As | CCAAT-binding (TF) | ? | [35,38,44,49] |
| miR171 |
M. truncatula, B. Juncea, O. sativa,
N. tabacum |
Hg, As, Cr, Cd | SCL (TF) | Shoot branching, signaling pathway |
[2,35,36,50] |
| miR192 | O. sativa | Cd | ABC gene | Seed germination of rice under Cd stress | [51] |
| miR268 | O. sativa | Cd | NRAMP3 | Inhibited rice seedling growth under Cd-stress treatment | [52] |
| miR319 | M. truncatula, B. juncea, M. truncatula | Hg, As, Al | TCP (TF), cyclin | Leaf morphogenesis, cell differentiation, embryonic development, cell division |
[47,50,53] |
| miR390 | O. sativa, M. truncatula, Glycine max L. | As, Al | tasi-RNA | Plant development | [40,54,55] |
| miR393 | A. thaliana, O. sativa, M. truncatula, Saccharum spp, H. vulgare | Cd, Hg, Al | TIR1/AFBs (F -box auxin receptors) and bHLH (TF) | Regulate auxin signaling | [41,50,56,57,58] |
| miR395 | A. thaliana, B. napus, Brassica parachinensis L. | Cd, As, Al | SLIM1, SULTR2;1, APS | Sulfur assimilation, response to cadmium ion, sulfate transport |
[43,59,60,61,62] |
| miR396 | O. sativa, N. tabacum, M. sinensis, M. truncatula, G. max | As, Cr, Al | GRF (TF) | Translation, leaf development | [36,37,40,43,55] |
| miR397 | A. thaliana, O. sativa, Populus trichocarpa T. | Cu, As, Cr | Laccase | Regulate inter-tissue lignification and secondary cell wall thickness, activities of PPO, SOD, and POD | [35,59,63,64,65,66] |
| miR398 | A. thaliana, O. sativa, P. trichocarpa | Cu, Cd | CSD1, CSD2, CCS1 and COX5b-1 | SODs relive oxidative stress | [34,65,67,68] |
| miR399 | O. sativa, N. tabacum | As | ? | ? | [36,43] |
| miR408 | A. thaliana, O. sativa, P. trichocarpa, O. sava | Cu, Cr, As | Laccase, plantacyanin transcripts, SPL7, HY5 | Regulate plastocyanin (PC) content | [63] [35,43,65,69,70] |
| miR444 | O. sativa | Cr | ? | ? | [35] |
| miR528 | O. sativa, A. thaliana, Z. mays | As, Al, Cd | MAX2 gene and l-resistant blo, LACod acid oxidase, MATE, LAC | Signal transduction, regulation of cell cycle, plant development, ascorbate metabolism, miRNA processing, control of cellular-free auxin levels | [43,54,70,71,72,73] |
| miR529 |
O. sativa,
M. truncatula |
As, Cd | Apetala2-like (TF), squamosa promoter binding protein-like (TF) | Signaling pathway, plant development | [43,50] |
| miR808 | O. sativa, | Al | Rockweed glycosyltransferase | ? | [74] |
| miR854 | B. juncea | As | Putative serine acetyl transferase (SAT) | Synthesis of O-acetylserine | [47] |
| miR857 | A. thaliana, | Cu | Laccase (LAC7) | ? | [33] |
| miR1318 | O. sativa | As | Calcium-binding proteins or Ca2+ ATPase | Signaling | [70] |
| miR1444 | P. trichocarpa | Cu | Cu-containing proteins, polyphenol oxidases (PPOs) | ? | [65] |
| miR1535b | G. max | Cd | Glyma07g38620.1 | Responsible for initial step of isopentenyl transferase |
[75] |