硫酯蛋白家族保守区域分析

硫酯蛋白家族(thioester-containing proteins,TEPs)广泛分布于动物界,在动物非特异性免疫反应中发挥了重要的作用,然而其家族成员多,分子进化关系复杂.本研究从基因数据库中挑取已收录TEPs家族各成员的氨基酸全序列,包括α2-巨球蛋白、补体3、补体4、murinoglobulins、卵巨球蛋白、妊娠区带蛋白,α-1-抑制因子等.多重序列比对分析TEPs家族各成员间功能位点和保守区域的变化,构建系统进化树分析TEPs家族分子进化.TEPs家族除保守的GC*EQ**硫酯键区域及两侧的脯氨酸残基,还有7个完全保守的氨基酸残基及G*****Q*T,FPETW,QTD,KPTVK等保守区域.上述分析结果可为深入研究TEPs家族分子进化及动物非特异性免疫进化提供参考.

An Initial Analysis of Sequence Conservation of Thioestercontaining Proteins(TEPs) Superfamily

Thioester-containing proteins(TEPs) were widely distributed in animal kingdom,and played an important role in innate immunity system.This study aimed to study the molecular characterization and motif variation of TEPs,and lead to an improved classification system for TEPs containing thioester bond with detailed sequence comparison.A PSI-BLAST search at NCBI was performed using Mus musculu alpha 2-macroglobulin as a query,and this superfamily includes alpha 2-macroglobulin,murinoglobulins,ovomacroglobulins,pregnancy zone proteins,alpha-1-inhibitor III,and complement proteins(complement) C3,C4.Then,multiple sequence alignments and phylogenetic analysis of TEPs domains were performed using the CLUSTALW program.The blasted results showed,except for conserved G**EQ** domain,there were about 12 fully conserved domains in all blasted sequences.Alignment of deduced amino acid sequence within TEPs showed that the over all structure of TEPs are evolutionarily conserved.In TEPs family,the function motifs were conserved with little variation,other amino acid sequences were low homologous.These analyses have established a framework of information about evolutionary relationships and conserved domains among the TEPs,which may facilitate research on these proteins as well as homologous molecules from other invertebrate species.