阿拉善双峰驼MSTN基因序列生物信息学分析

Bioinformatics analysis of the MSTN gene sequence in Alxa bactrian camel

为了研究阿拉善双峰驼肌肉生长抑制素(MSTN)基因,进一步探讨阿拉善双峰驼MSTN基因的结构及功能,试验采用5对引物对阿拉善双峰驼MSTN基因进行PCR扩增,所得产物进行序列拼接,利用生物信息学方法对阿拉善双峰驼MSTN基因的结构、理化性质及其编码蛋白信号肽、跨膜位置、亚细胞定位等进行分析,并讨论了阿拉善双峰驼与其他物种MSTN氨基酸序列的进化关系。结果表明:阿拉善双峰驼MSTN基因长7.3 kb,1~581 bp为第一外显子区,2 384~2 757 bp为第二外显子区,4 800~6 737 bp为第三外显子区。阿拉善双峰驼MSTN蛋白属于疏水性不稳定蛋白,18~19位氨基酸是最有可能的剪切位点,作为信号肽的可能性很大;二级结构中α-螺旋占22.40%,延伸链占26.67%,β-转角占7.73%,无规则卷曲占43.20%;阿拉善双峰驼MSTN蛋白有1个跨膜结构区域,其功能域可能位于278~375位氨基酸处。阿拉善双峰驼MSTN基因与哺乳类及灵长类动物的亲缘关系较近,与猪的亲缘关系最近(相似性高达99.2%)。说明阿拉善双峰驼MSTN基因编码的蛋白符合一般TGF-β超家族的结构特征,并符合已知MSTN蛋白的结构特征,与猪、灵长类及反刍类动物的分子进化距离较近。

The aim of the present study was to identify the Myostatin( MSTN) gene and analyze the structure and function of MSTN gene in the Alxa bactrian camel. 5 pairs of primers were used to amplify the MSTN gene of Alxa bactrian camel by PCR. The sequences of the products were spliced. The structure,physical and chemical properties of MSTN gene,signal peptide,transmembrane location and subcellular localization of MSTN gene in the Alxa bactrian camel were analyzed by bioinformatics method. The evolution of the MSTN amino acid sequence in Alxa bactrian camel and other species was also discussed. The results showed that the length of MSTN gene was 7. 3 kb. The region of 1-581 bp was the first exon,and the region of 2 384-2 757 bp was the second exon,the region of 4 800-6 737 bp was the third exon of the gene. There was a transmembrane domain in the MSTN protein,the 18 ~ 19 amino acids position was the most likely splicing site,and the peptide segment prior to the sit was the most likely signal peptides. The ratios of α-helix,extended strand,β-turn and random coil in the secondary structures were22. 40%,26. 67%,7. 73% and 43. 20%,respectively. The functional area might be located at the amino acid 278 ~ 375. The MSTN gene was closely related to mammals and primates,and the relationship with the pig was the closest( similarity was 99. 2%). The results indicated that the the protein encoded by MSTN gene in the Alxa bactrian camel was conformed to the structural characteristics of the general TGF-β superfamily,and conformed to the structural characteristics of the known MSTN protein. The molecular evolution distance of the MSTN protein was closed to the pigs,primates and ruminant.