真核翻译延伸因子1A蛋白家族功能位点的进化踪迹分析

真核翻译延伸因子1A（eEF1A）是真核生物蛋白质翻译过程中能将氨酰tRNA运送到核糖体A位点参与多肽延伸反应的多功能蛋白质. 本文主要利用多种生物信息学分析工具进行地中海涡虫翻译延伸因子1A（SmEF1A）蛋白序列的查找与eEF1A直系同源蛋白的搜索, 并基于90条直系同源蛋白进行eEF1A蛋白家族的进化踪迹分析和SmEF1A蛋白功能位点的比较研究. 结果表明，在eEF1A蛋白家族中共识别到338个踪迹残基位点和20个踪迹残基富集区域，SmEF1A蛋白的功能位点与踪迹残基位点密切相关，与GTP/Mg2+结合相关的S21、T72、D91、G94等重要位点均为全家族保守的踪迹残基,N 糖基化、磷酸化等蛋白修饰位点中踪迹残基位点往往是被修饰的部位或修饰功能发挥的关键辅助位点,而位于分子表面的配基结合口袋则与20个踪迹残基富集区域在分子表面形成的踪迹残基簇关系密切. eEF1A蛋白家族的进化踪迹分析为eEF1A蛋白重要功能区域关键残基的确定和未知功能位点的预测提供了重要信息.

Evolutionary Trace Analysis of Functional Sites of the eEF1A Family

Eukaryotic elongation factor 1 alpha (eEF1A) is a multifunctional protein family which delivers aminoacylated tRNA to the A site of ribosomes during peptide chain elongation. This study is conducted on the basis of searching EF1A protein sequence in Schmidtea mediterranea (SmEF1A) and eEF1A orthologous protein sequences through a variety of bioinformatics tools and performing evolutionary trace analysis of the eEF1A family with 90 orthologous protein sequences. This comparative study also was done to explore the functional sites of SmEF1A protein. The findings indicate that 338 trace residues and 20 trace residue rich regions are accumulated in eEF1A family, which are closely related to the functional sites of SmEF1A protein. The key amino acid sites including S21, T72, D91, G94 in binding GTP/Mg2+ are family conserved residues, and the modified sites or essential sites in N-glycosylation or phosphorylation modification process of protein are usually trace residues. Furthermore, the ligand-binding pockets located in the surface of SmEF1A protein have close relationships with trace residue clusters, which are composed of 20 trace residue rich regions. This research will provide useful information for identifying key residues from functional region and predicting unknown functional site in eEF1A family.