灯盏花R2R3-MYB转录因子基因家族鉴定与表达分析

Identification and expression profiling of R2R3-MYB transcription factors in Erigeron breviscapus

R2R3-MYB转录因子是植物中存在最为广泛的一类,参与植物的生长发育和次生代谢的调控。该文基于灯盏花基因组数据,采用生物信息学手段鉴定灯盏花中的R2R3-MYB转录因子,并对其基因序列、结构、理化性质进行分析,聚类分析预测灯盏花中的R2R3-MYB转录因子的功能;同时基于激素处理的转录组数据,对R2R3-MYB转录因子响应激素的表达模式进行分析。从灯盏花的基因组中共鉴定108个R2R3型MYB转录因子,分别命名为EbMYB1~EbMYB108,位于9条染色体上;基因结构显示,除个别MYB基因外,基本都含有2~4个外显子;构建灯盏花与拟南芥MYB家族成员的系统发育树,将234个MYBs分为的30个亚族,5个拟南芥亚族单独聚类成不同亚家族分支,有4个分支单独由灯盏花MYB基因聚类;转录组数据显示各MYB基因在灯盏花不同组织和ABA、SA、GA外源激素处理不同时间的差异表达,有13个R2R3-MYB基因的转录没有发生明显变化,部分基因的表达模式随着激素处理时间的增加呈现上调或下调的趋势。该研究为参与灯盏花生长发育、逆境(激素)胁迫以及活性成分灯盏乙素积累相关的R2R3-MYB转录因子调控机制的研究提供了理论依据。

R2 R3-MYB transcription factors are ubiquitous in plants,playing a role in the regulation of plant growth,development,and secondary metabolism.In this paper,the R2 R3-MYB transcription factors were identified by bioinformatics analysis of the genomic data of Erigeron breviscapus,and their gene sequences,structures,physical and chemical properties were analyzed.The functions of R2 R3-MYB transcription factors were predicted by cluster analysis.Meanwhile,the expression patterns of R2 R3-MYB transcription factors in response to hormone treatments were analyzed.A total of 108 R2 R3-MYB transcription factors,named EbMYB1-EbMYB108,were identified from the genome of E.breviscapus.Most of the R2 R3-MYB genes carried 2-4 exons.The phylogenetic tree of MYBs in E.breviscapus and Arabidopsis thaliala was constructed,which classified 234 MYBs into 30 subfamilies.The MYBs in the five MYB subfamilies of A.thaliala were clustered into independent clades,and those in E.breviscapus were clustered into four clades.The transcriptome data showed that MYB genes were differentially expressed in different tissues of E.breviscapus and in response to the treatments with exogenous hormones such as ABA,SA,and GA for different time.The transcription of 13 R2 R3-MYB genes did not change significantly,and the expression patterns of some genes were up-regulated or down-regulated with the extension of hormone treatment time.This study provides a theoretical basis for revealing the mechanisms of R2 R3-MYB transcription factors in regulating the growth and development,stress(hormone)response,and active ingredient accumulation in E.breviscapus.