中文摘要：

microRNA（miRNA）是一类内源性的、19～24碱基长度的小分子非编码RNA,通过碱基互补调控靶基因的表达,在多细胞生物的基因表达调控过程中扮演着十分重要的角色。植物中的miRNAs具有高度的保守性,这为通过同源比对发现保守的miRNAs提供了思路和途径。本研究通过对拟南芥、水稻等植物已知的miRNAs与玉米EST和GSS数据库的比对,并设置一系列严格的筛选标准,共筛选到23条新的玉米miRNAs;利用WMD3在线植物miRNAs靶基因预测软件,对新发现的玉米miRNAs进行靶基因预测,总共预测到89个靶基因,进一步功能分析发现,这些靶基因参与玉米的生长发育、信号转导、转录调节、新陈代谢及逆境胁迫响应等调控过程。

英文摘要：

microRNAs（miRNAs） are an extensive class of endogenous,non-coding,short（19–24 nt） RNA molecules directly involved in regulating gene expression at the post-transcriptional level and played an important role in gene expression regulation.Previous reports have noted that plant miRNAs are highly conserved,which provides the foundation for identification of miRNAs in plant species through homology alignment.With the method of bioinformatic computation,all previously known miRNAs in Arabidopsis,rice,and other plant species were blasted against maize EST（expressed sequence tags） and GSS（genomic survey sequence） sequences to select novel miRNAs in maize by a series of filtering criteria.A total of 23 conserved miRNAs were identified and predicted the target genes by a web-based integrated computing system,WMD 3.Total of 89 miRNA targets were predicted and verified to be involved in maize growth and development,signal transduction,transcriptional regulation,metabolism,and stress responses.