汉族人群花生四烯酸细胞色素P450ω-羟化酶4A11基因编码区结构的研究

Identification of Characterization and Variants of Arachidonic acid-Cytochrome P450 (-Hydroxylase 4A11 in Chinese Population

目的花生四烯酸由细胞色素P450ω-羟化酶催化生成的19-和20-羟烷四烯酸(19-, 20-HETE)。在多种疾病过程,尤其是高血压病中,20-HETE扮演着重要角色。寻找人群中该酶基因之一的CYP4A11的编码区多态性位点分布情况,可以为研究高血压病的基因机制提供新的依据。方法采集50例血压正常、无血缘关系的汉族人外周静脉血白细胞;提取基因组DNA;设计特异性引物,PCR法分段扩增基因编码区序列,电泳检测后回收目的片断;测序,与参考序列比对后统计结果。结果CYP4A11共发现16个多态性位点,其中5个有意义:1个5’端非编码区的突变位点A-54G,4 个引起氨基酸改变的多态性位点,分别为A6890C、A7207G、T7394A和T8590C。其余为同义突变或者位于内含子区。结论(1)多态性位点存在种族差异;(2)突变位点大多数位于内含子区,或者为同义突变,仅有少数有意义;(3)发现的多态性位点可能引起蛋白质构象进而改变蛋白质功能,或者引起基因转录活性的改变,并为下面的蛋白质组学研究和大样本人群研究奠定了基础。

Objective Arachidonic acid Cytochrome P450 （CYP） ω-hydroxylases catalyze arachidonic acid to produce 19- and 20-HETE, especially the later. 20-HETE may involve in a variety of pathophysiological conditions, especially primary hypertension. Identification of characteristics single nucleotide polymorphisms （SNPs） existing in coding region of the gene, CYP4A11, may provide some new insights into the genetic mechanisms of hypertension. Method Genomic DNA was extracted from blood white cells of 50 unrelated Chinese Han people with normotension. The coding regions were amplified by PCR, respectively. After sequenced, the information wan aligned and summarized. Results Sixteen SNP sites in CYP4A11 were identified,in which there are 5 sense mutation, including A-54G in 5′-uncoding region, A6890C, A7207G, T7394A and T8590C, which caused corresponding amino acid changing （K-T, S-G, F-Y and F-S）, respectively. Others were in intron region or nonsynonymous. Conclusion This study suggests that multiple variants exist within or near the CYP4A11 and CYP4F2 genes in Chinese populations. Most of variants were nonsense or in intron region. These SNPs or variants may change biologicalactivity of ω-hydroxylases. It may provide some directions for protein research consequently.