植物miRNA的功能及其作用机制

Advances in Studies on the Function and Mechanism of Plant MicroRNA

摘要:

miRNAs是真核生物中的一类5’端带磷酸基团、3’端带羟基、长度在22 nt左右的内源性非编码调控RNAs。miRNAs在控制植物的发育、开花时序、新陈代谢、应激反应等方面起着重要的作用。已知植物miRNAs在转录后水平上抑制基因表达，主要是通过导致mRNA的裂解，对抑制目标转录物的翻译起作用。另外其也能在转录水平上通过决定目标染色体位点的甲基化而起作用。对植物miRNAs的功能及作用机制的研究现状做一综述。

Abstract:

miRNAs are approximately 22-nucleotide endogenesis noncoding regulated RNAs in eukaryotes that have phosphate group at 5＇end and hydroxy group at 3＇end, which attract extensive attention in recent years. Scientists are now on the threshold of a better understanding how miRNAs works, miRNAs plays an important role in controlling plant development, florescence time, metabolism, response to stress, etc. Plant miRNAs are known to repress gene expression post-transcriptionally, mainly by guiding mRNA cleavage but also by attenuating the translation of target transcripts. In addition, it has been shown that plant miRNAs can also act at the transcriptional level by directing the methylation of target chromosomal loci. This paper reviews recent researches on the function and mechaism of plant microRNA.