大豆病程相关蛋白PR-5及其同源蛋白TPLs的生物信息学分析

Bioinformatics Analysis on Soybean Pathogenesis-related Protein(PR-5) and Its Homology Proteins TPLs

大豆病程相关蛋白PR-5又称为类甜蛋白TLPs,广泛分布于高等植物体内,各种生物和非生物胁迫诱导(病原微生物、渗透胁迫,机械损伤和植物激素等)均可诱导其表达。本研究以PR-5编码基因Glyma01g42670.1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;通过生物信息学的方法,共筛选获得42条大豆TLPs蛋白质序列,并用Mega 4.1软件构建其系统进化树;同时对Soy Base中的大豆TLPs相关的表达数据进行分析。结果表明:大豆病程相关蛋白PR-5的编码基因Glyma01g42670.1编码240个氨基酸的多肽链,p I 6.26,是一种酸性蛋白,属于疏水蛋白,该蛋白质具有典型的TLP家族的保守结构域,具有指导PR-5蛋白的跨膜转移(定位)的N端信号肽序列,PR-5蛋白不含有跨膜螺旋结构,主要存在于质外体中,属于分泌蛋白,推测该蛋白具有内切葡聚糖酶的催化活性,进化分析表明:该编码基因与拟南芥的NP_192902.1基因属于直系同源基因,它们是具有相同功能和共同起源的基因,组织表达特异性分析表明该基因主要在根部和花中表达。

Protein PR-5 of soybean is one of the PRs,known as TLPs,which exist in higher plants and can be induced to express by biotic and abiotic stress（ including pathogenic microorganisms,osmotic stress,mechanical damage and phytohormone etc.）. In present study,the structure and function of gene Glyma01g42670. 1 and its homologous protein were analyzed through bioinformatics,meanwhile 42 soybean TLPs protein sequences were collected to build a phylogenetic tree by software Mega 4. 1,and all the expression data of TLPs from website Soy Base were analyzed. The results showed： Gene Glyma01g42670. 1 coded peptide with 240 amino acids,and the protein was acidic and hydrophobic with p I 6. 26,which had typical domain as TLP family. It had N-terminal signal peptide leading protein membrane transportation,but without transmembrane helix structure,and mainly existed in apoplast. It belonged to secreted proteins and inferred to have endoglucanase catalytic activity. From the results of evaluation analysis,gene Glyma01g42670. 1 was the orthologous gene of gene NP_192902. 1from Arabidopsis,which had the same function and the same origin. From the results of tissue differential analysis,this gene mainly expressed in roots and flowers. All the research helps to clarify the function and molecular mechanism of how TLPs gene family did during the plant development.