黑腐病菌效应因子XopR的甘蓝靶标基因BobHLH34的克隆及功能分析  

Cloning and Functional Analysis of BobHLH34 Gene in Cabbage that Interacts with XopR from Xanthomonas

作　　者：韩睿 钟雄辉 陈登辉 崔建 乐祥庆 颉建明[1] 康俊根[2] HAN Rui;ZHONG Xionghui;CHEN Denghui;CUI Jian;YUE Xiangqing;XIE Jianming;KANG Jungen(Colleage of Horticulture,Gansu Agricultural University,Lanzhou 730070,China;Key Laboratory of Biology and Genetic Improvement of Horticultural Crops,Ministry of Agriculture and Rural Affairs,Beijing Vegetable Research Center,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China)

机构地区：[1]甘肃农业大学园艺学院,兰州730070 [2]北京市农林科学院蔬菜研究中心,农业农村部华北地区园艺作物生物学与种质创制重点实验室,北京100097

出　　处：《园艺学报》2023年第2期319-330,共12页Acta Horticulturae Sinica

基　　金：国家重点研发计划项目(2022YFD1200502);国家自然科学基金项目(31972408);北京市农林科学院创新能力建设专项(KJCX20210425,KJCX20200410)。

摘　　要：野油菜黄单胞菌(Xanthomonas campestris pv.campestris,Xcc)是十字花科作物黑腐病的致病菌。利用酵母双杂交系统,筛选到了野油菜黄单胞菌的效应因子XopR在甘蓝上的靶标蛋白BobHLH34,该蛋白基因的开放阅读框为996bp,编码331个氨基酸,含有1个保守性较高的碱性/螺旋—环—螺旋结构域(basic/helix1-loop-helix2)。系统进化树分析表明,甘蓝BobHLH34与花椰菜(BrcbHLH34)相似性最高,亚细胞定位结果显示其定位在细胞核内。将野油菜黄单胞菌接种甘蓝叶片,实时荧光定量结果显示BobHLH34的表达量呈现先上升后下降的趋势,接种后16h表达量达到峰值,为对照的7.7倍;利用甘蓝卷叶病毒载体BobHLH34-PCVA/PCVB真空侵染甘蓝实生苗能够有效降低BobHLH34的表达,导致基因沉默的甘蓝植株对野油菜黄单胞菌株的抗病性比对照显著降低。综上所述,BobHLH34能够正向调控甘蓝对黑腐病的免疫反应。Xanthomonas campestris pv.campestris(Xcc)is the causal agent of black rot of Brassicaceae crops.The cabbage protein BobHLH34 was found to be interacted with the effector XopR through the yeast two-hybrid system.The CDS of BobHLH34 was 996 bp encoding peptides with 331amino acids.It has a conserved domain(basic/helix1-loop-helix2).Phylogenetic tree analysis showed that bHLH34 proteins from Brassica cretica had the highest homology with BobHLH34 protein.The subcellular localization results showed that BobHLH34 was located in the nucleus.The qRT-PCR results showed that the expression of BobHLH34 was increased significantly after Xcc inoculation of cabbage leaves.The expression reached the peak at 16 h,which was 7.7 times that of the control.Vacuum infiltration of cabbage seedlings with the BobHLH34-PCVA/PCVB vector effectively down-regulated the expression of BobHLH34 gene,which resulted in susceptibility to Xcc.Taken together,BobHLH34 could positively regulate cabbage defense to black rot.

关 键 词：甘蓝 野油菜黄单胞菌 BobHLH34转录因子 VIGS XopR 

分 类 号：S635[农业科学—蔬菜学]