油菜ABCC家族基因生物信息学分析及其对镉胁迫的转录响应

Bioinformatics of ABCC family genes and their transcriptional response to cadmium stress in Brassica napus L.

为进一步解析ABCC家族基因在甘蓝型油菜中的生物学功能及其对土壤镉污染的响应,对在甘蓝型油菜中鉴定到的38个ABCC同源基因,从系统进化、染色体定位、基因结构以及对镉胁迫的转录响应方面进行分析。结果表明,甘蓝型油菜ABCC家族基因的进化分支都归属于拟南芥ABCC家族相应的分支,但ABCC9亚家族在甘蓝型油菜中缺失;大部分成员均属于较稳定的疏水蛋白;Ka/Ks值均小于1,受到强烈的纯化选择作用;基因结构变异较大,内含子数目在6~34之间,启动子区域能结合多种顺式作用元件,其中Dof丰度最大。38个BnaABCC分别定位在7条A染色体和8条C染色体上。共线性分析结果表明,甘蓝型油菜和拟南芥、白菜、甘蓝存在大量的同源基因。转录组分析显示,甘蓝型油菜ABCC家族基因受到镉胁迫的强烈诱导,其中BnaC1.ABCC3-2和BnaA6.ABCC4-3被分别确定为地上部和根部的主效基因。

To better understand the resistance of Brassica napus to soil cadmium(Cd)stress,ABCC family genes and their transcriptional response to Cd stress in B.napus were studied.38 ABCC homologs were identified,and were systematically analyzed on their phylogenetic evolution,chromosome location,gene structure and tran⁃scriptional response to Cd stress.Results revealed that all BnaABCC transporters fall into their corresponding clades of Arabidopsis thaliana,but ABCC9 was not found in B.napus.Most of the BnaABCCs were stable and hydro⁃phobic,and Ka/Ks ratio was less than 1,suggested the results of strongly purification and selection.Gene structures of BnaABCCs were varied,which were disrupted by 6-34 introns.Vast of cis-acting elements could bind to their promoters,Dof might be the richest one.38 BnaABCCs were mapped on chromosome 7 A and chromosome 8 C,and collinearity analysis showed abundant homologs in B.napus and Arabidopsis,B.rapa and B.oleracea.Transcriptome analysis showed that BnaABCCs were induced by Cd stress.Among them,BnaC1.ABCC3-1 and BnaA6.ABCC4-3 were identified as core genes in shoot and root respectively.