大豆过氧化物酶Ⅲ的生物信息学分析

Bioinformatics Analysis of Class Ⅲ Peroxidases in Glycine max

过氧化物酶Ⅲ(ClassⅢPOD)普遍存在于植物体内一类多基因家族蛋白,它属于一类PR蛋白;广泛参与植物的多种生理生化过程,在维持植物体内过氧自由基和H2O2处于稳定水平方面发挥着重要作用。本文通过生物信息学的方法,共筛选获得164条大豆过氧化物酶Ⅲ序列。以本实验室克隆得到的Glyma02g40040.1为目的基因,对该基因及其同源蛋白的结构和功能进行了分析,并用Mega4.0软件构建其系统进化树;同时对Soy Base中的大豆过氧化物酶Ⅲ的表达数据进行分析。结果表明:Glyma02g40040.1编码324个氨基酸,等电点为9.51,不存在跨膜结构域属于外分泌蛋白;与Gm Prx50的相似性达到93.85%,二级结构以σ螺旋为主,主要在花中和根中表达;大豆Gm Prxs基因具有明显的组织特异性表达模式。上述分析为进一步阐明过氧化物酶Ⅲ基因家族在植物生长发育过程中功能及分子机制奠定重要基础。

Class Ⅲ plant peroxidases are part of the polygene protein family; they are PR proteins, and they are normally present in plants. They are involved in a broad range of physiological and biochemical processes throughout the entire plant life cycle, and they also play an important role in maintaining plant peroxy radicals and H2O2 concentrations at a stable level. By searching the Perxi Base(http://peroxibase.toulouse.inra.fr/), 164 Class Ⅲplant peroxidase base sequences were obtained. The structure and function of the Glyma02g40040.1 gene and its homologous proteins were analyzed. Phylogenetic trees were then built with MEGA4.0 software, and gene expression profiles from the soybean database(www.soybase.com) were identified. The results indicated that Glyma02g40040.1 has 324 amino acids and that its isoelectric point is 9.51. There were no transmembrane structures.Class Ⅲ plant peroxidases belong to the exocrine proteins. The similarity of the Glyma02g40040.1 structure to that of Gm Prx50 was 93.85%, and its secondary structure was primarily composed of α helixes; the protein would be expressed in the flowers and stems. The expression patterns of the Gm Prxs were significantly different. This study provides an important foundation for a further functional dissection of the ClassⅢ plant peroxidases.