目的 对柴胡Bupleurum chinense R2R3-MYB转录因子家族进行鉴定与表达分析，为解析柴胡在盐胁迫下的次生代谢调控机制提供理论依据。方法 通过同源比对和隐马尔可夫模型筛选鉴定柴胡全部R2R3-MYB基因，系统解析其理化性质、系统进化关系、保守结构域、基因结构、顺式作用元件及染色体分布，并通过转录组测序分析其在200 mmol/L盐胁迫下的表达模式。结果 在柴胡基因组中共鉴定出116个R2R3-MYB转录因子，均为亲水性核定位蛋白，仅2个成员含跨膜结构域；系统发育分析显示其聚类为23个亚家族，主要分布于K、P、W、X亚家族；启动子区域含4类顺式作用元件，包括光响应、激素响应、胁迫响应、发育调控，其中光响应元件占比最高；基因复制事件共42对，串联重复3对，片段重复39对；盐胁迫表达谱显示有21个基因显著响应，根据表达模式分为早期响应型、中期持续性型、晚期抑制型。结论 对柴胡R2R3-MYB基因家族进行了全基因组鉴定、进化和盐胁迫表达分析，初步确定BcMYB59和BcMYB116这2个成员因其独特的结构特征和强烈的胁迫响应，成为解析柴胡盐胁迫应答机制及潜在跨膜信号感知功能的极佳候选基因。

Objective To identify and analyze the expression of R2R3-MYB transcription factor family of Bupleurum chinense, and provide a theoretical basis for analyzing the secondary metabolic regulation mechanism of B. chinense under salt stress. Methods All R2R3-MYB genes of B. chinense were screened and identified by homologous alignment and hidden Markov model. Their physical and chemical properties, phylogenetic relationship, conserved domains, gene structure, cis-acting elements and chromosome distribution were systematically analyzed, and their expression patterns under 200 mmol/L salt stress were analyzed by transcriptome sequencing. Results A total of 116 R2R3-MYB transcription factors were identified in the B. chinense genome, all of which were hydrophilic nuclear localization proteins, with only two members containing transmembrane domains. Phylogenetic analysis showed that they clustered into 23 subfamilies, mainly distributed in K, P, W, and X subfamilies. The promoters contained four types of cis-acting elements, including light response, hormone response, stress response, and development regulation, among which light response elements accounted for the highest proportion. There were 42 pairs of gene duplication events, including three tandem duplications and 39 fragment duplications. The salt stress expression profile revealed that 21 genes responded significantly, and they were classified into early response type, mid-term continuous type, and late inhibition type according to the expression patterns. Conclusion This study conducted a genome-wide identification, evolutionary analysis and salt stress expression analysis of the R2R3-MYB gene family in B. chinense. It was initially determined that BcMYB59 and BcMYB116, due to their unique structural features and strong stress response, are excellent candidate genes for understanding the salt stress response mechanism and potential transmembrane signal perception function of B. chinense.

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山东省创新公共服务平台项目-中药分子鉴定公共服务平台(2018JGX111); 山东省农业科学院“3237”齐鲁农科英才工程(创新类);山东省农业科学院农业科技创新工程项目(CXGC2025F13-1)