CBL1基因5'非翻译区内含子在旱生植物沙冬青中的作用

Effects of 5' UTR intron of AmCBL1 gene in a xerophyte Ammopiptanthus mongolicus

尽管内含子对mRNA转录的促进作用在真核生物中多有发现,但与胁迫相关的内含子的功能仍不甚清楚。本文构建了4个内含子的表达载体,并转化烟草,采用组织化学染色分析及GUS荧光染色分析法对其表达进行检测。结果表明,沙冬青中编码胁迫响应蛋白的AmCBL1基因的5'UTR内含子具有促进基因表达的功能。另外,5'UTR内含子的位置对基因表达的强度具有较强的预测能力。在不同逆境胁迫和激素诱导下,正向和反向插入的内含子均可促进基因的表达,但正常条件下,反向插入内含子的增强效果不及正向插入。研究结果为探索胁迫下基因表达的调控机制奠定了基础。

Introns increasing mRNA transcription have been found extensively in eukaryotes.However,not all of the introns could affect gene expression and functional profiles,especially stress-related profiles and introns having such effect are still unclear.In this study,four intron vectors were constructed and tested in tobacco by histochemical analysis and fluorometric analysis.Results showed that the 5＇ UTR intron of gene encoding the stress responsive protein AmCBL1 functionally elevated gene expression,and the orientation of 5＇ UTR intron was a strong predictor of its ability to increase expression.We found that the intron could enhance transcription when inserted in both the forward and reverse orientations under several stresses and hormones.However,transcriptional enhancement of intron in the opposite orientation under normal condition was not significant.This directionality of the inserted 5＇ UTR intron provides further insight into the regulation of gene expression.