人脑硫氧还蛋白还原酶基因的克隆及测序

Cloning and sequencing of human brain thioredoxin reductase

目的:从人脑组织中克隆硫氧还蛋白还原酶基因。方法;从胎脑中提取总RNA,采用RT-PCR技术,获得该基因的cDNA,构建pHBTR重组质粒,通过蓝白斑筛选及限制性内切酶鉴定,选择阳性克隆并测序。结果:测序结果显示该基因的开放读码框为1500 bp,用计算机软件处理后推导出相应的氨基酸序列为500个氨基酸的多肽链,将该基因与人胎盘TR基因比较发现两者的同源性为99％,在核苷酸序列上有5处碱基不同;且在氨基酸序列上也有4处不同。结论:首次获得中国人脑TR基因。

Objective:To clone the thioredoxin reductase (TR) gene from human fatal brain. Methods: The total RNA was extracted from human fatal brain; TR cDNA was obtained by RT-PCR method,and was cloned into pGEM-T vector, and then was transformed into E. Coli (DH5a); The positive transformant was identified with 2 groups of restriction en-donucleases; The positive clones was purified and sequenced. Results: The DNA sequence has been determined. Of the 1 513 base pairs sequenced, 1 500 base pairs were in an open reading frame encoding a mature protein with 500 amino acids; Identity to DNA sequence of TR gene from human placenta was 99% . There were 5 differences in the base pairs, and 4 differences in the amino acid sequences. Conclusion:The Chinese brain TR gene has been obtained firstly by us.