千里光β-微管蛋白基因结构与功能的生物信息学分析

Bioinformatic Analysis of Tubulin-beta Gene in Senecio scandens Buch.-Ham. ex D. Don

β-微管蛋白是影响细胞新陈代谢和行使功能的重要结构物质,研究β-微管蛋白基因的序列信息对揭示其蛋白结构与功能具有重要指导意义。从千里光全长cDNA文库中分离得到β-微管蛋白基因,并采用生物信息学软件进行序列分析。结果显示,该基因长度为1750 bp,编码的蛋白质长度为448个氨基酸,与柚子β-微管蛋白的同源性最高,达96%;其蛋白质分子量为50.01 kD,理论等电点为4.83。β-微管蛋白二级结构主要组成为无规则卷曲结构和α螺旋结构;结构域分析发现该蛋白具有两个保守结构域;三级结构预测为相对稳固的类球形结构;信号肽分析将该蛋白主要定位于细胞质、过氧化物酶体、线粒体基质等亚细胞器位置。将该基因序列上传至GenBank所获得的登录号为KF887495。本实验结果为千里光β-微管蛋白的作用机制揭示和应用研究提供了基础数据,也为植物β-微管蛋白基因的分子研究提供了理论依据及基础资料。

Beta-tubulin is an essential component in cell metabolism and function implementation. In this article,the Senecio scandens Buch.-Ham. ex D. Don beta-tubulin gene sequence was analyzed for its structure and function,as well as the relationship between them,through bioinformatics. The beta-tubulin nucleotide sequence was obtained from a formerly constructed full-length cDNA library of S. scandens,and was used as the query for a series of online bioinformatics tools. The S. scandens beta-tubulin gene was 1750 bp long,coding 448 amino acid residues,and shared 96% sequence identity with the beta-tubulin gene in Citrus maxima. This protein had a predicted molecular weight of 50. 01 kD and theoretical isoelectric point of 4. 83. The secondary structure of this protein mainly contained random coils and an alpha helix with two conserved domains. Its predicted tertiary structure was a relatively stable spherical structure. Signal peptide analysis revealed that the most probable sub-cellular locations of this protein were the cytoplasm,peroxisome and mitochondrial matrix space. This gene was uploaded to GenBank with the access number KF887495. This research lays a solidfoundation for future studies on function mechanism revelation and application for genetically improving S. scandens. This study also provides some basic data for studies on plant betatubulin.