番木瓜果实6个bHLH基因克隆及表达分析  

Cloning and Expression Analysis of Six bHLH Genes in Postharvest Papaya Fruit

作　　者：王楠[1] 年宇薇 邵远志[2] 李蕊 李雯[1] Wang Nan;Nian Yuwei;Shao Yuanzhi;Li Rui;Li Wen(Key Laboratory for Quality Regulation of Tropical Horticultural Crops of Hainan Province,School of Horticulture,Hainan University,Haikou,570228;SchoolofLifeSciences,HainanUniversity,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]海南大学生命科学学院,海口570228

出　　处：《分子植物育种》2022年第22期7374-7383,共10页Molecular Plant Breeding

基　　金：海南热带果蔬保鲜技术创新联盟项目(HDLM201901)资助。

摘　　要：bHLH转录因子是调控植物生长发育过程的第二大转录因子超家族,在植物生长发育和果实成熟过程中扮演着重要角色。为探究bHLH转录因子在‘日升’番木瓜(Carica papaya L.cv’SunUp’)果实采后贮藏期间的表达特性,本研究基于番木瓜转录组数据,通过TA克隆及RT-PCR技术,克隆得到了6个bHLH基因,命名为CpbHLH4~CpbHLH9。利用生物信息学方法对CpbHLH4~CpbHLH的理化性质,亲缘关系,保守结构域和进行分析。结果表明,6个bHLH基因序列全长663 bp(CpbHLH5)~1965 bp(CpbHLH9),具有完整的开放阅读框,编码221 aa(CpbHLH5)~654 aa(CpbHLH9)个氨基酸,除CpbHLH6表现为疏水性之外,其他5个bHLH蛋白均为亲水性蛋白,并且6个bHLH蛋白不具有跨膜结构和信号肽,预测定位于细胞核中。系统发育树和多序列比对结果显示,6个bHLH转录因子分布于不同的亚族,同时它们也都具有bHLH保守结构域。RT-qPCR结果表明CpbHLH4、CpbHLH5、CpbHLH6、CpbHLH7、CpbHLH8的表达水平在贮藏前期显著上调,而CpbHLH9的表达水平在果实成熟过程中持续降低。本研究鉴定了6个bHLH转录因子,明确了它们在采后番木瓜果实成熟过程中的表达模式,为进一步解析bHLH转录因子在采后番木瓜果实成熟中的功能和调控机制提供基础。The bHLH transcription factors(TFs)comprise the second largest superfamily of transcription factor and plays an important role in plant development and fruit ripening.In order to study the expression patterns of bHLH transcription factors in postharvest’SunUp’papaya fruit(Carica papaya L.cv’SunUp’)during storage time,six CpbHLH genes were cloned based on papaya transcriptome database by TA cloning and RT-PCR,named CpbHLH4~CpbHLH9.The physicochemical properties,phylogenetic relationships and conserved domains of CpbHLH4~CpbHLH9 were analyzed by bioinformatics methods.The results elucidated that CpbHLH4~CpbHLH9 contained an open reading frame of 663 bp(CpbHLH5)~1965 bp(CpbHLH9),encode 221 aa(CpbHLH5)~654 aa(CpbHLH9)amino acid residues.And five bHLH proteins were hydrophilic except CpbHLH6.In addition,six CpbHLH proteins were predicted to loc ate in the nucleus,without transmembrane structure and signal peptide.Moreover,phylogenetic tree and multiple sequence alignment showed that six CpbHLH proteins had bHLH conserved domains,but they were distributed in different subfamilies.Furthermore,RT-q PCR showed that the expression levels of CpbHLH4,CpbHLH5,CpbHLH6,CpbHLH7 and CpbHLH8 were significantly up-regulated at the early stage of storage,while the expression level of CpbHLH9 continued to decrease during fruit maturation.Our observations identified six bHLH transcription factors,and clarified their expression patterns during the process of postharvest papaya fruit ripening.Overall,these findings provide a preliminary basis for the future analysis of the functions and regulatory mechanisms of bHLH TFs in the process of metabolism in postharvest papaya fruit.

关 键 词：番木瓜(Carica papaya L.) 果实成熟 bHLH转录因子 表达分析 

分 类 号：S667.9[农业科学—果树学]