芸薹属AC基因组中VIT基因家族的鉴定与进化

Identification and evolution of VIT gene family between A and C genomes in Brassica

为了解液泡铁离子转运蛋白(vacuolar iron transporter,VIT)编码基因在芸薹属作物中的进化关系,在已完成的拟南芥、白菜、甘蓝以及甘蓝型油菜全基因组测序基础上,利用HMMER软件根据VIT保守的结构域对拟南芥、白菜、甘蓝和甘蓝型油菜全基因组的蛋白质序列进行同源检索,在四个物种中分别鉴定得到了9个、13个、12个和14个VIT候选基因;并且系统发育分析显示,VIT基因家族在四个物种可分为3类。VIT基因的启动子区域富含LTRE、ABRE、MYC、MYB和W-box等逆境应答相关顺式作用元件。蛋白质特性分析结果表明VIT结构域中具有多个保守的疏水氨基酸位点。表达谱分析显示所有VIT基因在所选取的组织中都有不同程度的表达。同时,线性对应的同源基因表达模式既有相似之处,又存在分化,而串联重复基因簇表达模式基本一致。

To understand the evolution of vacuole iron transporter( VIT) genes in Brassica,9,13,12 and 14 VIT candidate genes were identified in Arabidopsis thaliana,Brassica rapa,B. oleracea and B. napus respectively,based on genome- wide sequences of the 4 species,as well as the VIT conserved domain and HMMER software.Phylogenetic analysis showed that the VIT gene family was divided into 3 classes. In the promoter region,LTRE,ABRE,MYC,MYB and W- box cis elements were plentiful. Protein feature analysis indicated that the VIT domain contained more conservative hydrophobic amino acid residues. Gene expression profile showed that most of the VIT genes basically expressed in selected tissue in different levels. Syntenic related homologous genes presented both similar and diverse expression patterns,while the expression pattern of tandem duplicated genes were identical.