关键词: miRNA, 表达谱, 盐胁迫, 水稻

Abstract: miRNA is a kind of non-coding small RNA which plays an important regulatory role in vivo. miRNA mainly regulates gene expression at the post-transcriptional level and involves in various biological processes such as development and stress tolerance. High-throughput sequencing is one of the most effective methods for the identification of miRNA in plants. The total RNA was extracted from roots, stems and leaves from rice treated with high salt stress. Small RNAs were isolated to construct sRNA libraries. The libraries were sequenced using high-throughput method, and the miRNA expression profiles were analyzed. The results showed that 248 known miRNA from 132 different families were detected in all samples. Totally, 31 differentially expressed miRNAs were identified in root, 11 in stem and 9 in leaf, which belonged to 29 miRNA families, targeting 592 functional genes. Five differentially expressed miRNAs, responding stress tolerance, were further analyzed. The results showed that Osa-miR166h and miR166k were up-regulated, and miR169h and miR530 were down-regulated. The miR169 target genes were investigated using qPCR, and three of four target genes were up-regulated with miR169 down-regulation. Above results indicated that miRNA played an important role in plants stress tolerance.

Key words: miRNA, expression profile, salt stress, rice