Quality and Basic Sciences, Directorate of Wheat Research, Karnal, 132001, India,
Plant Mol Biol. 2014 Jan;84(1-2):1-18. doi: 10.1007/s11103-013-0120-6. Epub 2013 Aug 23.
The human population is increasing at an alarming rate, whereas heavy metals (HMs) pollution is mounting serious environmental problem, which could lead to serious concern about the future sufficiency of global food production. Some HMs such as Mn, Cu, and Fe, at lower concentration serves as an essential vital component of plant cell as they are crucial in various enzyme catalyzed biochemical reactions. At higher concentration, a vast variety of HMs such as Mn, Cu, Cd, Fe, Hg, Al and As, impose toxic reaction in the plant system which greatly affect the crop yield. Recently, microRNAs (miRNAs) that are small class of non-coding riboregulator have emerged as central regulator of numerous abiotic stresses including HMs. Increasing reports indicate that plants have evolved specialized inbuilt mechanism viz. signal transduction, translocation and sequestration to counteract the toxic response of HMs. Combining computational and wet laboratory approaches have produced sufficient evidences concerning active involvement of miRNAs during HMs toxicity response by regulating various transcription factors and protein coding genes involved in plant growth and development. However, the direct role of miRNA in controlling various signaling molecules, transporters and chelating agents of HM metabolism is poorly understood. This review focuses on the latest progress made in the area of direct involvement of miRNAs in signaling, translocation and sequestration as well as recently added miRNAs in response to different HMs in plants.
人口正以惊人的速度增长，而重金属 (HM) 污染是一个严重的环境问题，这可能会引发人们对未来全球粮食生产是否充足的严重担忧。一些 HM，如 Mn、Cu 和 Fe，在较低浓度下作为植物细胞的必需生命组成部分，因为它们在各种酶促生化反应中至关重要。在较高浓度下，大量的 HM，如 Mn、Cu、Cd、Fe、Hg、Al 和 As，会在植物系统中引起毒性反应，从而极大地影响作物产量。最近，作为一类小的非编码核糖调控因子的 microRNAs (miRNAs)，已成为包括 HM 在内的多种非生物胁迫的中央调控因子。越来越多的报道表明，植物已经进化出专门的内置机制，即信号转导、转运和螯合，以抵抗 HM 的毒性反应。结合计算和湿实验室方法已经产生了足够的证据，表明 miRNAs 通过调节参与植物生长和发育的各种转录因子和蛋白质编码基因，在 HM 毒性反应中积极参与。然而，miRNA 在控制 HM 代谢的各种信号分子、转运蛋白和螯合剂方面的直接作用还知之甚少。这篇综述重点介绍了 miRNA 在信号转导、转运和螯合以及最近在植物中对不同 HM 响应中直接参与的最新进展。
