【摘要】 真核细胞中存在大量的非编码RNA,～22nt的小RNA是其中一类非常重要的调控RNA,主要包括siRNA和miRNA两种类型,二者均由类似RNaseⅢ的核酸内切酶-Dicer加工产生,随后进入沉默复合体抑制靶基因表达。miRNA分子与siRNA类似,但miRNA的前体在基因组上具有独立的转录单位,可自身折叠成发卡结构,其靶基因主要是与器官发生及生长发育相关的转录因子以及调控蛋白。miRNA在生物生长发育的各个时期都扮演着重要的角色,调控许多重要的生物途径,处于基因调控网络的核心位置。更多还原

【Abstract】 Non-coding RNAs are abundant in eukaryotic cells, of which small RNAs constitute a family of regulatory RNAs of ~22nt in length. siRNA and miRNA are the two major types, both of which are produced by RNase III-like enzymes called Dicer in plants. They are incorporated into silencing complexes to guide repression of target genes. miRNAs are chemically and functionally similar to siRNAs but are derived from local stem-loop structures in the genome. miRNAs have recently been shown to play critical roles at each major stage of plant development, regulating a number of key pathways. They typically act at the core of a gene regulatory network, mostly targeting transcription factors and regulatory proteins that are involved in organ morphogenesis and plant development.更多还原