甘蓝型油菜BnWRKY41的理化性质分析及BnWRKY41-2在花青素合成中的功能解析

Physicochemical Properties Analysis of BnWRKY41 and Functional Characterization of BnWRKY41-2 in Anthocyanin Biosynthesis in Brassica na pus

甘蓝型油菜BnWRKY41-1通过负调控花青素合成相关基因的表达而显著抑制拟南芥叶片花青素的积累。为深入了解同源拷贝BnWRKY41-2在花青素合成过程中的作用,对BnWRKY41-1和BnWRKY41-2进行生物信息学分析,并从甘蓝型油菜品种‘中双11’中成功克隆BnWRKY41-2的全长编码序列,分别转化烟草和拟南芥wrky41-2突变体,对其亚细胞定位和在花青素合成中的调控作用进行分析。结果表明,Bn-WRKY41两个拷贝均具有典型WRKY结构域,N端不含跨膜结构和信号肽,二级结构主要由无规则卷曲组成,蛋白质修饰以磷酸化为主。BnWRKY41-2定位在细胞核中,在拟南芥wrky41-2突变体背景下异源表达BnWRKY41-2基因使突变体叶片中的花青素含量恢复到野生型水平,而且可显著调控花青素积累相关基因的表达。这些结果表明BnWRKY41-2与BnWRKY41-1在蛋白质结构及理化性质方面相似,并且在调控拟南芥叶片花青素积累方面发挥类似的生物学功能,起负调控作用。

BnWRK Y41-1 significantly inhibits anthocyanin accumulation in rosette leaves by negative-ly regulating the expression of anthocyanin biosynthesis genes in Arabidopsis thaliana.To further un-derstand the role of the paralog BnWRKY41-2 in anthocyanin biosynthesis,in the present study,bioinformatics analysis of BnWRKY41-1 and BnWRKY41-2 was performed.Subsequently,the coding domain sequence of Bn WRKY41-2 from the B.napus cultivar‘Zhongshuang 11’were obtained and transformed into tobacco and A.thaliana wrky41-2 mutant,respectively.And finally,the subcellular localization and the regulation in anthocyanin biosynthesis of BnWRK Y41-2 were analyzed.The results showed that both of BnWRKY41-1 and BnWRKY41-2 had typical WRKY domains,and the N-termi-nal did not contain transmembrane structure and signal peptide.The secondary structure was mainly composed of random coil,and the protein modification was mainly phosphorylation.BnWRKY41-2 was localized in the nucleus of tobacco leaf cells.Under the background of the A.thaliana wrky41-2 mutant,the heterologous expression of the Bn WRK Y41-2 gene not only restored thehigher leaf antho-cyanin phenotype of the mutant to the wild type,but also significantly regulated the expression of an-thocyanin biosynthesis genes.These results indicate that BnWRKY41-2 is similar to BnWRKY41-1 in protein structure and physicochemical properties,and reveal a conserved role in negatively regulating anthocyanin accumulationin Arabidopsis leaves.