植物miRNA作用方式的分子机制研究进展

Advances on the Molecular Action Mechanisms of Plant miRNA

miRNA是一类真核生物中广泛存在的约20-24个核苷酸长度的内源单链非编码RNA分子。植物miRNA通过剪切mRNA或抑制翻译负调控基因表达,在细胞增殖分化、个体生长发育和抵御逆境胁迫等生理过程中发挥重要作用。自2002年首次发现植物miRNA以来,miRNA迅速成为植物分子生物学领域的研究热点,数十年的研究已经使植物miRNA生物发生、降解、调控植物生长发育等机制及作用得到了清晰的阐述;但是对植物miRNA作用机制的认知仍然处于初级阶段,尤其是miRNA介导翻译抑制的分子机制仍有待挖掘。概述了植物miRNA介导的m RNA剪切和翻译抑制的研究历史和最新进展,探讨了两种机制的影响因素和相互关系,并提出了未来的研究方向和思路,以期为深入了解植物mi RNA的作用机制及促进miRNA的基础研究和实际应用提供理论依据。

microRNAs(miRNAs)are a class of 20-to 24-nucleotide(nt)endogenous noncoding single-stranded RNAs widely exisitng in eukaryote.miRNAs in plants negatively regulate the expressions of target genes through mRNA cleavage or translation repression and play important roles in cell proliferation and differentiation,growth and development of an individual,and responses to environmental stresses.Since the first identification of plant miRNAs in 2002,research on miRNAs has become a hotspot in the field of plant molecular biology.Decades of research have elucidated the mechanisms of miRNA biogenesis and degradation and revealed the regulatory roles of miRNAs in numerous biological processes in plants.However,mechanisms underpinning the action of plant miRNAs are still not well understood,especially with respect to miRNA-mediated translation repression.This review summarizes both historical perspectives and the latest progress on the plant miRNAs-mediated mRNA cleavage and translation repression,discusses the influencing factors and relationship of two mechanisms,and suggests the research direction and thoughts in future,aiming at providing a theoretical basis for in-depth understanding of the mechanism of plant miRNA and promoting the basic research and practical application of miRNA.