星油藤细胞分裂素反应调节子基因PvoRR22克隆及表达分析

Cloning and expression analysis of cytokinin response regulator PvoRR22 in Plukenetia volubilis

关键词:  星油藤, 细胞分裂素反应调节子, PvoRR22, 响应元件, 表达模式

Key words:  Plukenetia volubilis, cytokinin response regulators, PvoRR22, response elements, expression patterns

摘要:

细胞分裂素反应调节子(RRs)是细胞分裂素信号转导通路上的重要组分,其中RR22是C型反应调节因子。该文基于星油藤基因组和转录组数据库,克隆了PvoRR22基因,并对其生物信息学及不同组织部位和6-苄基腺嘌呤(6-BA)处理花序芽中的表达模式进行了分析。结果表明:(1)PvoRR22编码含170个氨基酸的蛋白。PvoRR22蛋白分子量为18.65 kDa,理论等电点为4.54且为亲水性蛋白,定位于细胞核。(2)系统进化分析表明星油藤PvoRR22与蓖麻和南欧大戟来源的RR22关系较近。(3)PvoRR22启动子序列含有大量光响应、昼夜节律与逆境胁迫响应及脱落酸、生长素和茉莉酸等激素响应顺式作用元件。(4)PlantRegMap分析发现PvoRR22的表达可能受MYB和ERF转录因子家族的调控。(5)PvoRR22主要在星油藤的根、茎和茎尖中表达,其中在根中的表达量最高; 在6-BA处理的花序芽中,PvoRR22的表达量在12 h时达到最高。综上认为,PvoRR22可能在星油藤根、茎和茎尖的生长发育及细胞分裂素信号转导方面发挥功能。该结果为将来研究PvoRR22的功能奠定了基础。

Abstract:

Cytokinin response regulators(RRs)are key components of cytokinin signal transduction pathways, and RR22 belongs to type-C RR subfamily. PvoRR22 was cloned based on the Plukenetia volubilis genome and transcriptome database, and its bioinformatics and expression patterns of different tissues and inflorescence buds treated with 6-benzyladenine(6-BA)were analyzed in this study. The results were as follows:(1)PvoRR22 encoded a protein of 170 amino acids with a calculated molecular mass of 18.65 kDa and a theoretical isoelectric point of 4.54. PvoRR22 was characterized as a hydrophilic protein and localized in the nucleus.(2)Phylogenetic analysis revealed the closest evolutionary relationship of PvoRR22 was the homologs from Ricinus communis and Euphorbia peplus.(3)PvoRR22 promoter sequences contained a large number of cis-acting elements those responded to light, a circadian rhythm and abiotic stress, and hormones including abscisic acid, auxin, and jasmonic acid.(4)PlantRegMap analysis revealed that PvoRR22 might be primarily regulated by the transcription factors of MYB and ERF family.(5)PvoRR22 was principally expressed in the roots, stems, and stem apexes of Plukenetia volubilis, with the highest expression levels in the roots. The expression levels of PvoRR22 peaked at 12 h in inflorescence buds after 6-BA treatment. In conclusion, PvoRR22 may play an important role in the growth and development of the roots, stems, and stem apexes in P. volubilis, as well as in cytokinin signal transduction. This study lays a foundation for further research on the function of PvoRR22.