中文摘要：

microRNA（miRNA）是来自真核生物自身基因组的非编码小分子RNA,在转录后水平上负调控基因表达,在植物的生长发育和胁迫应答等方面起重要作用.以栽培草莓艳丽为试材,利用RT-PCR 技术克隆草莓叶片中5 种新miRNA 的前体及靶基因,分析靶基因的结构特征与功能,结果表明：草莓miR-6,miR-12,miR-13,miR-14,miR-29 的前体长度分别为513 bp,309 bp,464bp,334 bp 和343 bp,均能形成典型的茎环结构,其中miR-12、miR-13 的成熟miRNA序列在茎环3＇ 端臂上,miR-6、miR-14、miR-29成熟miRNA序列在茎环的5＇ 端臂上.miR-14 与miR-29 的靶基因分别为854bp 和690bp,与森林草莓基因组对应序列-致性为98.72%和99.42%,其中miR-29 靶基因是GRP基因,编码143个氨基酸,推测miR-29 靶基因在草莓植株的胁迫响应中有重要调控作用.本研究丰富了草莓miRNA的研究,为揭示草莓miRNA的生物学功能奠定基础.

英文摘要：

microRNAs are small, non-coding RNAs from eukaryotic genomes that act to negatively regulate the expression of theirtarget genes at the post-transcriptional levels, and play important roles in the plant growing development and their response toenvironmental stresses. The precursors of five novel miRNAs and their target genes were cloned by using RT-PCR methods fromleaves of cultivated strawberry, Yanli, and characteristic and function of the targets genes were analyzed. The results showed that theprecursors lengths of miR-6, miR-12, miR-13, miR-14 and miR-29 were 513 bp, 309 bp, 464 bp, 334 bp and 343 bp,respectively. They could form typical stem-loop structure. Among them, the mature miRNAs of miR12 and miR13 located in the 3＇end of stem-loop, and the mature miRNAs of miR-6, miR-14 and miR-29 were at the 5＇ end of stem-loop. The target genes ofmiR-14 and miR-29 were 854bp and 690bp in length, and their identities of sequences were 98.72% and 99.42% comparing withcorresponding sequence in strawberry genome. The target gene of miR-29 was GRP, encoded a predicted protein of 143 amino acidresidues. So we deduce it has the important regulated function in their response to environmental stresses of strawberries. Theresults will enrich the research on strawberry miRNA and lay the foundation of the biological function of strawberry miRNA.