千里光肌动蛋白基因(Actin)的生物信息学及功能分析

Functional Analysis of Actin Gene from Senecio scandens Buch.-Ham.ex D.Do Based on Its Bioinformatics

肌动蛋白(Actin)是广泛存在于高等植物中的组成型表达蛋白质,与细胞分裂、细胞运动、细胞信号转导等功能密切相关。为明确肌动蛋白性质与功能的关系,本研究从千里光全长cDNA文库中分离得到Actin基因。序列分析结果表明:该基因长度为1 481 bp,编码360个氨基酸残基的多肽,与甘草Actin基因编码的氨基酸序列(GenBank登录号:ABW71681.1)的同源性最高,达96%;预测蛋白质的分子量为40.02 kDa,理论等电点为5.85;结构分析发现,螺旋结构和无规则卷曲构成Actin二级结构的主要组分;三级结构预测发现,Actin具有4个结构域;蛋白系统发生树发现,与甘草和鹰嘴豆的亲缘关系较近。本研究认为,高等植物Actin可能参与基因的转录调控,其氨基酸突变位点未对功能结构域产生影响。

Actin, a constitutively expressed protein in higher plants, was closely related to the function such as cell division, cell movement and cell signal transduction. In order to learn the relationship between characteristics and functional roles, actin genes from full-length cDNA library in Senecio scandens Buch. -Ham. ex D. were isolated, and it was found to share 96% indentity with Glycyrrhiza uralensis（ GenBank accession： ABW71681.1 ） using bioinformatics analysis. In the present study, actin protein was composed cf 360 amino acid residues with the predicted molecular weight of 40.02 kDa and the theoretical isoelectric point of 5.85. Analyses of domain and structure indicated that the protein was dominantly composed of the imperative curls and the loosed helixes, with 4 domains in three-dimensional level. The phylogenetic tree of 28 species suggested that closer relationship was observed among S. scandens, Cicer arietinum, and G. uralensis. Notably, it was concluded that actin protein might play an important role in the regulation of gene transcription in higher plants, without changeable advanced structure even if a few amino acid mutation sites.