中文摘要：

MicroRNA（miRNA）是由约22个核苷酸组成的内源性非编码小分子RNA,广泛存在于真核细胞中,通过与靶基因的互补配对在转录后水平对基因表达进行调控,导致mRNA的降解或翻译抑制。本文通过对目前miR-Base中收录的miR396家族进行生物信息学分析发现,该家族在植物界中高度保守,它们可能起源于较为古老的物种,经历长期复杂的进化过程而保留了下来;靶基因预测结果显示生长调控因子GRF为其主要靶标;启动子分析表明,miR396编码基因的上游存在光、温度、激素、厌氧、干旱及病害等胁迫响应相关的顺式作用元件,它们可与转录因子结合,参与多种胁迫应答反应。本文可为全面深入研究miRNA的作用机制奠定基础。

英文摘要：

MicroRNAs （miRNAs） are small endogenous non-coding RNAs with about 22 nucleotides emerging as a key regulator of g@e activity at post-transcriptional level in eukaryotic cells. They negatively target mRNA that containing highly complementary sequences by either cleavage or translational repression. In this study, we analyzed the miR396 gene family in miRBase by utilizing bioinformatics methods. The results showed that miR396 was quite conserved in plant; it originated from ancient ancestor and experienced significant complex evolution; target prediction indicated miR396 mainly regulated GRF. Promoter analysis identified many stress- related cis-acting elements in the upstream region of miR396 genes, such as light, heat, anoxic, hormone, drought and biotic responses, which can bind transcription factors and participate in the miR396 during stress. Our survey established foundation for deeply elucidate the regulatory regulatory activities of mechanism of miRNA.