过氧化氢酶基因CsKat01与柑橘溃疡病相关性分析

Correlation Analysis of Citrus Catalase Gene CsKat01 and Citrus Canker Disease

为了探究过氧化氢酶基因Cs Kat01在柑橘抵御溃疡病过程中的作用,对感病品种‘晚锦橙’和抗病品种‘四季橘’中Cs Kat01进行了生物信息和表达分析,并探究了溃疡病菌接种处理后两品种中CAT酶活性和H2O2含量的关系。克隆Cs Kat01的编码序列并对该基因及其编码蛋白进行结构和功能分析,发现Cs Kat01编码框全长为1482bp,共编码493个氨基酸残基,蛋白序列中含有典型的CAT结构域;通过启动子序列克隆和分析发现‘晚锦橙’和‘四季橘’核心启动子区域均含有水杨酸、茉莉酸和脱落酸的响应元件,但数量不同;利用q RT-PCR分析水杨酸、茉莉酸、脱落酸和柑橘溃疡病菌(Xcc)对Cs Kat01的诱导表达特性,发现Cs Kat01的高表达可能使柑橘相对更感病;结合Xcc诱导后植物组织中Cs Kat01酶活性和H2O2含量,综合分析Cs Kat01、CAT酶活、H2O2含量和柑橘对溃疡病抗性之间的关系,推测Cs Kat01基因可能通过调控CAT的酶活性,改变H2O2含量进而影响柑橘对溃疡病的抗性。

In order to investigate the correlation between Cs Kat01 and citrus bacterial canker disease(CBCD)response,bioinformatics and expression analysis of Cs Kat01 as well as the relationship between CAT activity and Hydrogen peroxide(H2 O2)contents in CBCD susceptible variety Wanjincheng and resistant variety Calamondin were performed. Firstly,the coding sequence(CDS)of the Cs Kat01 gene was cloned and the structure and function of the coding protein were analyzed. The full-length CDS of Cs Kat01 is 1 482 bp and it encodes 493 amino acid residues with a typical catalase domain. Secondly,by cloning and analyzing the promoter sequence,we studied the promoter regulatory elements and found that the core promoters of both Wanjincheng and Calamondin contained salicylic acid(SA),jasmonic acid(JA)and abscisic acid(ABA)response elements whose numbers are different. Thirdly,q RT-PCR was used to analyze the induced expression profiles of plant hormones and Xanthomonas citri subsp. citri(Xcc)on Cs Kat01,and then the correlation between the enzyme and CBCD was determined. Finally,the relations between Cs Kat01,CAT activity,H2 O2 content and CBCD resistance were analyzed. We speculate that Cs Kat01 may regulate CAT enzyme activity,which further regulates H2 O2 accumulation,and then regulates CBCD resistance.