大白菜低温胁迫转录因子BcICE1的克隆及表达分析

Cloning and Expression Analysis of Cold Stress Transcription Factor BcICE1 from Brassica pekinensis

本研究采用RT-PCR结合SON-PCR技术从大白菜(Brassica pekinensis)中分离了BcICE1基因的cDNA序列(GenBank登录号为HQ902162)。该基因全长1591bp,含有一个1494bp长的开放阅读框,编码497个氨基酸。序列比对表明,该蛋白C端含有一个典型的bHLH结构域,与其他植物的ICE1蛋白具有较高的同源性。进化树分析表明,BcICE1蛋白与盐芥和山嵛菜的bHLH蛋白处在同一进化分枝。半定量RT-PCR分析表明,BcICE1基因是冷诱导条件下差异表达的基因。利用所构建的大肠杆菌表达载体,实现了BcICE1基因在原核系统的特异性表达。

The cDNA sequence of BcICE1 gene was successfully isolated from Brassica pekinensis by RT-PCR and SON-PCR. The full-length cDNA of BcICE1 was 1 591 bp with a 1 494 bp open reading frame （ORF） encoding 497 amino acid residues. Sequence multialigment demonstrated that the C-terminal of deduced BcICE1 protein exhibited a typical bHLH domain and was high identity with other ICE1 proteins from different species. The homology tree showed that BcICE1 was at the same evolutionary branch with EsICE1 and ThICE1. The s-qRT-PCR result suggested that BcICE1 was difference expression gene under low temperature stress. The BcICE1 gene was successfully expressed in the prokaryotic expression system with constructed expression vector in Escherichia coli.