油茶bHLH基因家族鉴定与响应干旱胁迫的基因表达分析  

Identification of bHLH gene family in Camellia oleifera and analysis of its expression under drought stress

作　　者：谢荟清 苏文娟 赵娜红 程钦华 朱鸿洋 樊昊琦 胡冬南[1,2] 刘娟[1,2] XIE Huiqing;SU Wenjuan;ZHAO Nahong;CHENG Qinhua;ZHU Hongyang;FAN Haoqi;HU Dongnan;LIU Juan(Jiangxi Provincial Key Laboratory of Subtropical Forest Resources Cultivation,Jiangxi Agricultural University,Nanchang 330045,Jiangxi,China;College of Forestry,Jiangxi Agricultural University,Nanchang 330045,Jiangxi,China)

机构地区：[1]江西农业大学亚热带森林资源培育江西省重点实验室,江西南昌330045 [2]江西农业大学林学院,江西南昌330045

出　　处：《中南林业科技大学学报》2025年第1期168-180,共13页Journal of Central South University of Forestry & Technology

基　　金：江西省自然科学基金面上项目(20232BAB205054);江西省林业局油茶研究专项项目(YCYJZX{2023}114号);江西省研究生创新专项资金项目(YC2023-S354)。

摘　　要：【目的】探究油茶bHLH基因家族成员及其应对干旱胁迫的表达调控模式。【方法】基于油茶全基因组数据,鉴定CobHLHs基因成员,分析其系统发育进化关系,研究其在油茶染色体上的分布、顺式作用元件预测、家族成员间共线性分析,探究CobHLHs基因的组织表达特异性及其在干旱胁迫、ABA处理下的表达模式。【结果】共鉴定出127个CobHLHs。根据其系统发育关系,将其分为17个亚族。共线性分析结果显示,全基因组范围内共发生了22次片段复制事件。干旱胁迫下叶组织转录组分析结果显示,共有106个CobHLHs参与油茶干旱胁迫响应过程。组织特异表达分析发现,参与干旱胁迫的CobHLHs主要在叶中高表达,在根中表达相对较低。PEG模拟干旱胁迫和同源基因功能预测证实,9个CobHLHs的表达均在不同程度上受干旱胁迫诱导,不同基因表达调控模式存在差异,CobHLH071在干旱胁迫下为低表达,表现为12、48 h分别为对照的0.07和0.24倍;CobHLH006、CobHLH082在干旱胁迫下高表达,CobHLH006在12、48 h为对照的8.2、54.1倍,而CobHLH082在48 h才出现显著高表达。进一步进行ABA处理研究其可能的表达调控模式发现,CobHLH071可能通过ABA依赖负调控干旱胁迫应答。CobHLH006、CobHLH082可能通过影响ABA信号通路相关基因的表达,正调控油茶干旱胁迫应答,但两者的响应时间存在差异,前者可能同时存在非ABA依赖调控模式。【结论】大部分CobHLHs基因在干旱胁迫下参与响应,其中CobHLH071、CobHLH082在干旱胁迫下和ABA处理下均出现响应,且两者响应方式不同,研究进一步表明CobHLH可能通过不同方式参与ABA信号途径响应干旱胁迫。【Objective】This study aimed to explore the bHLH gene family members of Camellia oleifera and their expression and regulation mode in response to drought stress.【Method】This research based on complete genomic data from C.oleifera to identify CobHLH family members,investigate their evolutionary connections,map their positions on chromosomes,forecast their cis-regulatory elements,and assess the conservation of gene order among family members.Additionally,the study aimed to delineate the tissue-specific expression profiles of CobHLHs and to examine their expression dynamics in response to drought stress and ABA treatment.【Result】A total of 127 CobHLH gene were identified in the study.They were classified into 17 distinct subfamilies based on their evolutionary relationships.The collinearity analysis revealed 22 segmental duplication events spanning the entire genome.When examining the leaf tissue’s transcriptome under drought conditions,it was found that 106 CobHLHs played a role in drought stress response.Furthermore,the tissue-specific expression analysis indicated that those CobHLHs implicated in drought stress response were predominantly highly expressed in leaves and comparatively less so in roots.Using PEG to simulate drought stress,along with predictions of homologous gene functions,demonstrated that the expression levels of 9 CobHLH genes were modulated by drought to varying extents,highlighting disparities in their regulatory mechanisms.Specifically,CobHLH071 exhibited reduced expression under drought conditions,with levels 0.07 and 0.24 times that of the control at 12 and 48 hours post-stress,respectively.In contrast,CobHLH006 and 082 displayed robust expression under drought stress.CobHLH006 showed a significant upregulation,being 8.2 and 54.1 times the control levels at 12 and 48 hours after the onset of drought stress.CobHLH082 also showed a marked increase in expression,particularly at the 48-hour mark following drought stress.Further investigation into the potential regulatory mechanisms

关 键 词：油茶 bHLH基因家族 表达分析 干旱胁迫 

分 类 号：S722.5[农业科学—林木遗传育种]