柑橘HSP20家族基因鉴定及其响应溃疡病菌侵染表达分析  

Identification of HSP20 Family Genes in Citrus and Their Expression in Pathogen Infection Responses Citrus Canker

作　　者：张凯[1] 麻明英 王萍 李益 金燕[1] 盛玲 邓子牛[1] 马先锋[1] ZHANG Kai;MA Mingying;WANG Ping;LI Yi;JIN Yan;SHENG Ling;DENG Ziniu;MAXianfeng(Engineering Research Center for Horticultural Crop Germplasm Creation and New Variety Breeding,Ministry of Education,National Center for Citrus Improvement Changsha,College of Horticulture,Hunan Agricultural University,Changsha,410128,China)

机构地区：[1]湖南农业大学园艺学院,园艺作物种质创新与新品种选育教育部工程研究中心,国家柑橘改良中心长沙分中心,长沙410128

出　　处：《园艺学报》2022年第6期1213-1232,共20页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(31720103915);湖南省自然科学基金项目(2020JJ4040);湖南创新型省份建设专项(2019RS1052)。

摘　　要：为探究HSP20在柑橘(Citrus L.)响应溃疡病菌(Xanthomonas citri subsp.citri,Xcc)侵染过程中发挥的作用,鉴定CsHSP20家族基因。生物学信息分析显示共有42个,分为11个亚族,分布在9条染色体上,编码135~373个氨基酸,蛋白分子量15.17~41.71 kD,等电点4.53~10.07,92.9%的基因没有或只有1个内含子,各亚族基因间有高度相似的结构和保守基序,每个基因的启动子都具有与激素或胁迫相关的顺式作用元件。其次,对感病的冰糖橙和抗病的枸橼C-05进行接种Xcc和40℃热胁迫处理,qRT-PCR结果显示CsHSP20家族中的HSP17.9、HSP23.3、HSP18.5和HSP18.0均上调表达,但抗感材料之间差异明显,HSP23.3在枸橼C-05中受Xcc上调表达水平极显著,该结果与受Xcc侵染的转录组结果一致。在冰糖橙叶片瞬时超表达候选基因,Xcc定量分析结果显示枸橼C-05的HSP23.3抑制Xcc繁殖速度更明显。Citrus canker,caused by is a bacterial disease,which severely influence citrus industry,and its pathogenicity is significantly enhanced under higher temperature and humidity environmental condition.HSP20 genes are abundant and highly conserved in higher plants,they play vital defense roles when plants are under biotic or abiotic stress.In order to investigate the role of HSP20 genes in response to Xanthomonas citri subsp.citri infection,the genes of HSP20 family in Citrus sinensis were identified.The analysis of biological information showed that there are 42 members,which can be divided into 11 subfamilies,they encode 135-373 aa and are distributed on nine chromosomes,their protein molecular weight are from 15.17 to 41.71 kD,isoelectric point are from 4.53 to 10.07,almost 92.9%of them not contain any intron or only one,and each subfamily share highly similar structures and conserved motifs,their promoter also has cis-acting elements response to hormones or stress.In order to access the role of CsHSP20 in response to Xcc and abiotic stress in resistant germplasm Citron C-05 with susceptible sweet orange,we have injected Xcc into the leaves of Citron C-05 and conducted a series of heat stress with small Citron C-05 plants.The relative expression levels of CsHSP20 have been screened by qRT-PCR,the results showed that HSP17.9,HSP23.3,HSP18.5 and HSP18.0 were up-regulated in both Xcc and heat stress,but their relative expression level in Citron C-05 is notably different from that of sweet orange under Xcc infection,especially HSP23.3.Interestingly,the induced expression patterns are consistent with the result of the transcriptomic analysis infected by Xcc.Then,these genes have been transiently overexpressed in sweet orange leaves,and Xcc quantitative analysis of Citron C-05 HSP23.3 showed that Xcc reproduction was inhibited.

关 键 词：柑橘 枸橼 HSP20 溃疡病 表达分析 

分 类 号：S666[农业科学—果树学]