辣椒CaBBX2基因的克隆与表达分析  

Cloning and Expression Analysis of CaBBX2 Gene in Pepper

作　　者：柳佳欣 吴丹 陶思政 罗英 杨凤 余婷 杨有新[1] 周勇 LIU Jiaxin;WU Dan;TAO Sizheng;LUO Ying;YANG Feng;YU Ting;YANG Youxin;ZHOU Yong(College of Agronomy,Jiangxi Agricultural University/Jiangxi Provincial Key Laboratory for Postharvest Storage and Preservation of Fruits&Vegetables,Nanchang,Jiangxi 330045;College of Bioscience and Bioengineering,Jiangxi Agricultural University/Key Laboratory of Crop Physiology,Ecology and Genetic Breeding,Ministry of Education,Nanchang,Jiangxi 330045)

机构地区：[1]江西农业大学农学院/果蔬贮藏与保鲜江西省重点实验室,江西南昌330045 [2]江西农业大学生物科学与工程学院/作物生理生态与遗传育种教育部重点实验室,江西南昌330045

出　　处：《核农学报》2024年第9期1671-1681,共11页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金(32160739);江西省自然科学基金-面上项目(20232BAB205039);江西省主要学科学术和技术带头人培养计划青年人才项目(20204BCJL23044)。

摘　　要：为探究BBX转录因子在辣椒抵御疫霉菌侵染过程中的功能,本研究以辣椒品种007EA为材料,对辣椒BBX转录因子CaBBX2基因进行克隆和表达分析,并对其编码蛋白进行亚细胞定位和生物信息学分析。聚合酶链式反应(PCR)扩增和测序结果表明,CaBBX2的编码区序列长为639 bp,编码212个氨基酸。蛋白理化分析结果显示,CaBBX2蛋白分子量为23.5 kDa,理论等电点(pI)值为6.17,总平均亲水系数为-0.559,表明CaBBX2为亲水性蛋白。蛋白质结构预测及蛋白序列比对结果显示,CaBBX2含有2个B-box保守结构域。进化树分析结果显示,CaBBX2蛋白属于Ⅳ亚组的BBX蛋白,与拟南芥AtBBX18和AtBBX19蛋白亲缘关系最近。启动子分析结果显示,CaBBX2启动子序列中含有与胁迫、激素和光响应有关的顺式作用元件。亚细胞定位结果显示,CaBBX2同时定位于细胞质和细胞核。组织特异性表达发现,CaBBX2基因在辣椒不同组织中均有表达,其中在叶中的表达量最高,在果皮中的表达量最低。采用实时荧光定量PCR(qRT-PCR)分析CaBBX2在疫霉菌接种及茉莉酸甲酯(MeJA)处理后表达量的变化,发现接种疫病后CaBBX2的表达量明显上升,MeJA处理后CaBBX2表达量呈现明显下降趋势。上述结果表明CaBBX2可能参与激素调控响应辣椒疫病胁迫的应答过程,可为辣椒抗病分子育种提供重要的候选基因。To investigate the role of B-box(BBX)transcription factor in response to Phytophthora capsici infection in pepper,the BBX transcription factor CaBBX2 was cloned and its expression patterns were analyzed using pepper variety 007EA as material in this study.The subcellular localization and bioinformatics analysis of its encoded protein were also performed.The PCR amplification and sequencing results showed that the CDS of CaBBX2 was 639 bp in length,encoding a protein containing 212 amino acids.Physical and chemical analysis indicated that CaBBX2 protein had a molecular weight of 23.5 kDa,pI value of 6.17,and GRAVY value of-0.559,suggesting that CaBBX2 is a hydrophilic protein.The protein structure prediction and sequence alignment results revealed that CaBBX2 harbored two conserved B-box domains.Phylogenetic tree analysis showed that CaBBX2 belonged to the groupⅣBBXs and was most closely related to Arabidopsis AtBBX18 and AtBBX19.Promoter analysis revealed that the promoter of CaBBX2 contained a number of stress-,hormone-,and light-responsive cis-acting elements.The results of subcellular localization showed that CaBBX2 was located in both the cytoplasm and nucleus.Tissue expression analysis results showed that CaBBX2 was expressed in different pepper tissues,with the highest expression in leaves and the lowest expression in pericarp.Quantitative real-time PCR was used to examine the expression of CaBBX2 under P.capsici infection and MeJA treatment.It was found that the expression of CaBBX2 was increased after P.capsici infection,while its expression displayed a significantly decreased tendency under MeJA treatment.These findings indicated that CaBBX2 may play a key role in hormone-regulated defense response against P.capsici infection,providing an important candidate gene for molecular breeding of pepper disease resistance.

关 键 词：辣椒 BBX转录因子 疫霉菌 表达分析 

分 类 号：S641.3[农业科学—蔬菜学]