目的 基于连翘Forsythia suspensa基因组数据筛选鉴定bHLH转录因子家族成员并进行特征与功能分析。方法 利用连翘基因组数据筛选鉴定连翘bHLH转录因子家族，分析其蛋白理化性质、系统进化关系，并对bHLH基因进行染色体定位、基因结构、功能注释、顺式作用元件分析等特征分析。此外，采用外源茉莉酸甲酯（methyl jasmonate，MeJA）处理连翘叶片，通过qRT-PCR检测FsbHLHs在处理后48 h内的表达模式，并结合连翘脂素含量变化进行相关性分析。结果 筛选出170条具有完整HLH保守结构域的bHLH转录因子，分布在14条染色体上，编码氨基酸长度在67～885个aa，相对分子质量在7 910.58～98 854.78，理论等电点（pI）为4.71～10.44，系统发育分析将其划分为13个亚家族，其中第III亚家族成员最多。通过顺式作用元件分析，FsbHLHs具有多种光调控、激素响应和胁迫响应相关的元件。对筛选获得的8个FsbHLH基因在MeJA处理下的表达模式与连翘脂素含量变化进行相关性分析，结果表明FsbHLH26和FsbHLH139 2个基因极有可能在连翘脂素的合成与积累中发挥关键调控作用。结论 筛选鉴定了170个FsbHLH基因家族成员，对其进行系统的生物信息学分析和MeJA处理下基因表达模式分析，筛选到FsbHLH26和FsbHLH139可能是参与到连翘脂素生物合成的关键转录因子，为探究连翘脂素生物合成的分子机制奠定基础。

Objective To screen and identify members of the bHLH transcription factor family based on genomic data from Forsythia suspensa and characterize their features and functions. Methods Using the genomic data of F. suspensa, the bHLH transcription factor family was screened and identified, analysing their physicochemical properties and phylogenetic relationships, and characterizing the bHLH genes by analysing their chromosomal locations, gene structures, functional annotations, and cis-acting elements. In addition, F. suspensa leaves were treated with exogenous methyl jasmonate (MeJA) and expression pattern of FsbHLHs within 48 h after treatment was detected by qRT-PCR. Correlation analysis was conducted in combination with the changes in phillygenin content. Results A total of 170 bHLH transcription factors with complete HLH conserved domains were identified, and these factors were distributed across 14 chromosomes. Their amino acid lengths ranged from 67 to 885 aa, relative molecular masses from 7 910.58 to 98 854.78, and theoretical isoelectric points (pI) from 4.71 to 10.44. Based on phylogenetic analysis, FsbHLHs were grouped into 13 subfamilies, with subfamily III being the largest. Through cis-acting element analysis, it was found that FsbHLHs contained multiple elements associated with light regulation, hormone response, and stress response. Subsequently, the correlation between MeJA-induced expression of eight FsbHLH genes and phillygenin content was analysed, and these results suggested that FsbHLH26 and FsbHLH139 were potentially critical regulators of phillygenin biosynthesis and accumulation. Conclusion This study identified 170 members of the FsbHLH gene family. Through systematic bioinformatics analysis and gene expression pattern analysis following MeJA treatment, FsbHLH26 and FsbHLH139 may be the key transcription factors involved in the biosynthesis of phillygenin, laying the foundation for future research into the molecular mechanisms underlying phillygenin biosynthesis.

R282.12

河南省中央引导地方科技发展资金项目（Z20241471030）；中央本级重大增减支项目“名贵中药资源可持续利用能力建设项目”（2060302）；河南省科技攻关项目（242102110325，262102110326）；河南省中药材产业科技特派员服务团项目