铁十字秋海棠R2R3-MYB基因家族的鉴定及表达分析

Identification and expression analysis of R2R3-MYB gene family in Begonia masoniana

  • 摘要: 【目的】 对铁十字秋海棠(Begonia masoniana)R2R3-MYB基因家族进行鉴定分析,并检测R2R3-MYB基因家族成员在铁十字秋海棠叶片不同生长发育时期中叶斑区和非叶斑区的表达模式,为铁十字秋海棠叶斑分子调控机制和叶色改良及新品种培育提供理论参考。【方法】 以铁十字秋海棠3个关键生长发育时期的叶片为试验材料,参考拟南芥R2R3-MYB家族蛋白序列,利用生物信息学方法从铁十字秋海棠基因组数据库中鉴定出R2R3-MYB基因家族成员,并对其理化性质、染色体定位、系统发育、基因结构、保守基序及启动子顺式作用元件等进行预测分析,并通过实时荧光定量PCR检测7个BmaMYBs基因在铁十字秋海棠3个生长发育期中叶斑区和非叶斑区的表达模式。【结果】 从铁十字秋海棠基因组中鉴定出110个R2R3-MYB基因家族成员,该基因家族成员的氨基酸数量为128~870个,分子量为14660.85~97435.93 Da,理论等电点(pI)为4.92~10.10,成员之间差异较大,大部分为不稳定的疏水性蛋白,均定位在细胞核。110个R2R3-MYB家族基因在15条染色体上均有分布,部分基因在同一染色体上集中分布,形成基因簇;BmaMYBs含有0~10个内含子;约94%的成员含有Motif 1、Motif 2和Motif 3基序;R2R3-MYB基因家族成员启动子均含有大量光响应元件;BmaMYB10、BmaMYB18、BmaMYB38、BmaMYB53、BmaMYB97、BmaMYB99BmaMYB109基因在叶片发育过程中叶斑区与非叶斑区均有表达,叶斑区BmaMYB53基因的相对表达量较非叶斑区高达19.41~131.99倍。【结论】 在铁十字秋海棠基因组中鉴定出110个R2R3-MYB基因家族成员,叶斑区与非叶斑区BmaMYB53基因的相对表达量差异最大,推测该基因是调控铁十字秋海棠叶斑形成的关键基因。

     

    Abstract: 【Objective】 Identification and analysis of the R2R3-MYB gene family in Begonia masoniana was conducted,and the expression patterns of the R2R3-MYB gene family members in different growth stages of leaf spots and non-leaf spot regions was detected,providing theoretical reference for understanding the molecular regulatory mechanisms underlying leaf spot formation in B. masoniana,as well as for leaf color improvement and new variety breeding. 【Method】 Using leaves from 3 key growth and development periods of B. masoniana as experimental materials,with Arabidopsis thaliana R2R3-MYB family proteins as reference sequences,members of the R2R3-MYB gene family from the B. masoniana genome database were identified using bioinformatics methods. Then predicted and analyzed their physicochemical properties,chromosomal localization,phylogenetic relationships,gene structures,conserved motifs and promoter cis-acting elements. Additionally,examined the expression patterns of 7 BmaMYBs genes in the leaf spot region and non-leaf spot region during 3 growth and development periods of B. masoniana through real-time fluorescence quantitative PCR. 【Result】 A total of 110 members of the R2R3-MYB gene family were identified from the genome of B. masoniana. These gene family members had amino acid quantity ranging from 128 to 870,molecular weights ranging from 14660.85 to 97435.93 Da,and theoretical isoelectric points(pI)ranging from 4.92 to 10.10. There were great differences among the members,with most being unstable hydrophobic proteins,and all of them located in the nucleus. The 110 R2R3-MYB family genes were distributed across all 15 chromosomes,with some genes concentrated on the same chromosome forming gene clusters. BmaMYBs contained 0-10 introns;approximately 94% of the members contained Motif 1, Motif 2 and Motif 3;and the promoter regions of R2R3-MYB gene family members contained a large number of lightresponsive elements. During leaf development,BmaMYB10,BmaMYB18,BmaMYB38,BmaMYB53,BmaMYB97,BmaMYB99 and BmaMYB109 genes were expressed in both leaf spot and non-leaf spot regions;relative expression level of the BmaMYB53 gene in the leaf spot region was as high as 19.41 to 131.99 times compared to that in non-leaf spot region. 【Conclusion】 In the genome of B. masoniana,110 members of the R2R3-MYB gene family are identified. The relative expression level difference between the leaf spot region and non-leaf spot region is the greatest for BmaMYB53 gene,suggesting that this gene is a key regulator in the formation of leaf spots in B. masoniana.

     

/

返回文章
返回