水稻低温胁迫响应microRNA鉴定

Identification of Rice′s MicroRNA in Response to Low Temperature Stress

水稻是世界三大粮食作物之一,然而低温胁迫会严重抑制水稻的生长发育。为了探究microRNA在水稻低温胁迫中的作用,采用低温处理前、5℃低温处理24 h和5℃低温处理48 h的2~3叶期水稻整株,构建9个小RNA文库。通过高通量测序后,对9个小RNA文库的microRNA进行差异表达分析,一共筛选出21个与冷胁迫相关的microRNA,其中16个在冷胁迫下上调,5个在冷胁迫下下调。通过对这21个microRNA靶基因的GO富集结果表明,其靶基因广泛富集在包括信号转导、免疫系统和物质合成等细胞内过程中。这表明水稻可能通过多种microRNA介导,从各个方面来协同抵御低温胁迫。本研究为进一步阐明microRNA响应低温胁迫的分子机制提供了基础,且本研究所鉴定的microRNA为增强水稻对低温耐受性遗传改良提供了优异的miRNA资源。

Rice is one of the three major food crops in the world.However,low temperature stress will seriously inhibit the growth and development of rice.In order to explore the role of miRNA in rice under low temperature stress,nine small RNA libraries were constructed by taking the whole plant of 2 ~ 3 leaf rice before low temperature treatment,5 ℃ low temperature treatment for 24 hours and 5 ℃ low temperature treatment for 48 hours.Through high-throughput sequencing and differential expression analysis of miRNAs in 9 small RNA libraries,21 miRNAs related to cold stress were screened,of which16 were up-regulated and 5 were down regulated under cold stress.The GO enrichment results of these 21 miRNA target genes showed that their target genes were widely enriched in intracellular processes including signal transduction,immune system and substance synthesis.This suggests that rice may cooperate to resist low temperature stress through a variety of miRNAs.The results of this study provide a basis for further elucidating the molecular mechanism of miRNA response to low temperature stress,and the miRNA identified in this study provides excellent miRNA resources for enhancing the genetic improvement of low temperature tolerance in rice.