西藏桑桑牦牛CXCR2基因克隆及生物信息学分析

Cloning and Bioinformatics Analysis of CXCR2 Gene in Tibetan Sangsang Yak

为了研究牦牛CXCR2基因的结构、生物学功能及影响牦牛生长发育的机制,以西藏桑桑牦牛脂肪组织cDNA为模板,利用RT-PCR克隆牦牛CXCR2基因的编码区序列(Coding sequence,CDS),并对其进行生物信息学分析、结构域预测及蛋白理化性质预测,利用RT-qPCR技术进行组织表达分析。结果表明,桑桑牦牛CXCR2基因的CDS区全长876 bp,共编码291个氨基酸;结构域预测结果显示,在CXCR2氨基酸序列的1~245位有1个Pfam家族的7tm_1结构域;CXCR2蛋白分析预测结果显示,该蛋白有5个跨膜结构,无信号肽区域,分子量32855.55 Da,原子总数4726个,分子式为C_(1524)H_(2416)N_(392)O_(374)S_(20),不稳定性指数29.45,表明该蛋白质为稳定蛋白,理论等电点9.86,脂肪系数120.27,总平均亲水系数-0.657,为疏水性蛋白,共有21个磷酸化位点;亚细胞定位预测结果显示,桑桑牦牛CXCR2基因主要分布于内质网(55.6%)、线粒体(22.2%)和细胞核(22.2%)中;系统进化树结果显示,桑桑牦牛与瘤牛亲缘关系最近,与水牛亲缘关系最远。

In order to study the structure,biological function of yak CXCR2 gene,and the mechanism that affects the growth and development of yak,the coding sequence(CDS)of yak CXCR2 gene was cloned by RT-PCR using the adi‐pose tissue cDNA of Tibet Sangsang yak as a template.The gene sequence was used for bioinformatics analysis,struc‐tural domain prediction and protein physicochemical property prediction,and then RT-qPCR was used for tissue ex‐pression analysis.The results showed that the CDS region of the CXCR2 gene of Sangsang yak was 876 bp in length,encoding 291 amino acids.The structural domain prediction of the CXCR2 gene of the yak showed that there was a 7tm_1 structural domain of the Pfam family at position 1-245 of the amino acid sequence of the CXCR2,and the analy‐sis of the protein showed that there were five transmembrane structures and no signal peptide region.The moleculor weight was 32855.55 Da.Its total number of atoms was 4726.Molecular formula was C_(1524)H_(2416)N_(392)O_(374)S_(20).Instability index was 29.45.It indicated that the protein was a stable protein with the theoretical isoelectric point of 9.86,fat coeffi‐cient of 120.27,and the total average hydrophilicity coefficient of-0.657.It was the hydrophobic proteins with a total of 21 phosphorylation sites.The subcellular localization showed that the CXCR2 gene was mainly distributed in the endo‐plasmic reticulum(55.6%),mitochondria(22.2%)and nucleus(22.2%)of the Sangsang yak.The phylogenetic tree showed that the Sangsang yak was the closest to the zebu,and the farthest from the buffalo.