肝豆状核变性基因突变的生物信息学分析  

A bioinformatics analysis of gene mutation in Wilson disease

作　　者：李艳艳[1] 张东锋[1] 

机构地区：[1]郑州人民医院,河南郑州450000

出　　处：《中医临床研究》2016年第25期56-59,共4页Clinical Journal Of Chinese Medicine

摘　　要：目的:分析预测肝豆状核变性(WD)基因突变与蛋白结构、功能改变的关系,为WD的早期基因诊断与治疗提供参考。方法:选取符合Wilson病诊断标准的患者6例及健康对照者6名作为研究对象,用盐析法抽提受试者基因组DNA并进行测序鉴定,检测受试者WD基因突变情况;通过生物信息学分析手段分析预测WD基因的生物学特性及理化性质,对WD基因编码蛋白及发生基因突变的外显子进行同源模建,分析基因突变与其空间构象变化的关系。结果:6例患者中有3例为第8外显子突变(2例为Arg778Leu,1例为Arg778Gln),有2例为第12外显子突变(Thr935Met和Arg919Gly),1例为第7外显子突变(Trp650Ser);蛋白生物信息学分析发现,蛋白总体带负电荷,不稳定指数45.26,蛋白分子量为157.23k Da,蛋白具有两亲性分子的特点;蛋白有8个跨膜区,二级结构主要有α-螺旋,无规则卷曲,延伸结构及β-转角;同源模建结果显示,778位氨基酸的突变导致外显子8的空间构象发生明显改变;而外显子12的935和919位氨基酸突变则对其空间构象影响不大。结论:778位氨基酸突变或许不是一个温和突变,该位点的突变对本病的发生影响更为深刻。Objective： The relationship among gene mutation, protein structure and change of function in Wilson disease was analyzed, to provide a reference for the early diagnosis and treatment. Results： 6 cases of Wilson disease and 6 cases of healthy people were selected. DNA in subjects were sequenced by salting-out method, and gene mutation in WD subjects were tested. Biological characteristics and physicochemical properties of WD gene were analyzed and predicted by the bioinformatics analysis. The protein encoded by WD gene and gene mutation in exon were given homology modeling. And relationship between gene mutation and conformational changes was analyzed. Results： In 6 cases, 3 cases suffered from mutation in exon 8（1 case in Arg778Leu, 1 case in Arg778Gln）. 2 cases suffered from mutation in exon 12（Thr935Met and Arg919Gly）; 1 case suffered from mutation in exon 7（Trp650Ser）. Protein bioinformatics analysis revealed that protein overall showed negative electric charge; instability index was 45.26, and protein molecular was157.23kDa. Protein is amphiphilic molecule, and has 8 transmembrane region, with α-helix, random coil, extending structure andβ-corner in secondary structure. Results of homology modeling showed that change of spatial conformation in exon 8 resulted from mutation in amino acid 778, while mutation in amino acid 935 and 919 showed little effect on spatial conformation in exon 12. Conclusion： Mutation in amino acid 778 may not mild, and profoundly affect on the disease.

关 键 词：WILSON病 生物信息学 同源模建 第8外显子 基因突变 

分 类 号：R394[医药卫生—医学遗传学]