黄灯笼辣椒MYB4转录因子的克隆与序列分析  

Cloning and Sequence Analysis of MYB4 Transcription Factor in Huangdenglong Pepper

作　　者：张威 张丽平 吴丹[1] 成善汉[1] 汪志伟[1] 刘平武 Zhang Wei;Zhang Liping;Wu Dan;Cheng Shanhan;Wang Zhiwei;Liu Pingwu(Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province,College of Horticulture,Hainan University,Haikou,570228;Fang Zhiyuan Academician Team Innovation Center of Hainan Province,Haikou,570228)

机构地区：[1]海南大学园艺学院,海南省热带园艺作物品质调控重点实验室,海口570228 [2]海南省方智远院士团队创新中心,海口570228

出　　处：《分子植物育种》2023年第6期1801-1810,共10页Molecular Plant Breeding

基　　金：国家自然科学基金项目(31760578);海南省自然科学基金高层次人才项目(2019RC030)共同资助。

摘　　要：MYB转录因子是最大的转录因子家族之一,存在于所有真核生物中。R2R3型MYB是植物中最常见的MYB转录因子类型,它调控着植物组织发育、非生物胁迫反应和代谢等多种生物学过程。本研究从海南黄灯笼辣椒(Capsicum chinense)中克隆分离CcMYB4-2 (PHU22609.1)和CcMYB4-12 (PHT97629.1)转录因子,这两个转录因子是典型的R2R3型MYB。CcMYB4-2基因的ORF(开放阅读框)为753 bp,编码250个氨基酸,分子量为28.74 kD,理论等电点为9.39,CcMYB4-12基因的ORF为810 bp,编码269个氨基酸。CcMYB4-2和CcMYB4-12均不含信号肽,无跨膜结构域,是一类不稳定的非分泌亲水蛋白。进化关系得出,CcMYB4-12与拟南芥AtMYB4、AtMYB7、AtMYB32聚类在一起,已知AtMYB4、AtMYB7、AtMYB32可抑制苯丙烷代谢路径上木质素和类黄酮的合成,推测CcMYB4-12在辣椒中可能通过抑制木质素和类黄酮代谢途径,从而调节辣椒素的合成。对这对基因的启动子区域进行预测,含有多个激素响应元件和逆境响应元件。qPCR分析得出,CcMYB4-12表达量在花后10~40 d逐渐升高,40 d达到最高,与辣椒合成趋势较为相似,CcMYB4-2在花后20 d表达量达到最高,后逐渐降低,与辣椒合成趋势相反。本研究结果为进一步研究辣椒中辣椒素的生物合成调控机制奠定了理论基础。MYB transcription factor is one of the largest transcription factor families and is present in all eukaryotes.R2R3 MYB is the most common type of MYB transcription factor in plants,which regulates a variety of biological processes such as plant tissue development,abiotic stress response and metabolism.In this study,transcription factors CcMYB4-2(PHU22609.1)and CcMYB4-12(PHT97629.1)were cloned and isolated from Hainan Huangdeng long Pepper(Capsicum chinense).These two transcription factors are typical R2R3 TYPE MYB.The ORF(open reading frame)of CcMYB4-2 gene was 753 bp,encoding 250 amino acids with molecular weight of 28.74 kDa and theoretical isoelectric point of 9.39.The ORF of CcMYB4-12 gene was 810 bp,encoding 269 amino acids.CcMYB4-2 and CcMYB4-12 are unstable non-secretory hydrophilic proteins without signal peptides and transmembrane domains.CcMYB4-12 is clustered with AtMYB4,AtMYB7 and AtMYB32 in Arabidopsis thaliana.AtMYB4,AtMYB7 and AtMYB32 are known to inhibit lignin and flavonoid synthesis in phenylpropane metabolic pathway.It is speculated that CcMYB4-12 may regulate the synthesis of capsaicin by inhibiting the metabolic pathways of lignin and flavonoids in pepper.This predicts the promoter region of the gene,which contains multiple hormone-responsive and stress-responsive elements.qPCR analysis showed that CcMYB4-12 expression increased gradually on 10~40 days after anthesis and reached the highest level on 40 days,which was similar to the synthesis trend of pepper.CcMYB4-2 expression reached the highest level on 20 days after anthesis and decreased gradually after that,which was contrary to the synthesis trend of pepper.The results of this study lay a theoretical foundation for further study on the biosynthesis and regulation mechanism of capsaicin in capsaicin.

关 键 词：CcMYB4转录因子 黄灯笼 辣椒素合成 生物信息学 

分 类 号：S641.3[农业科学—蔬菜学]