Shibata F, Takagi Y, Kitajima M, Kuroda T, Omura T
Division of Molecular Genetics, School of Medicine, Fujita Health University, Japan.
Genomics. 1993 Jul;17(1):76-82. doi: 10.1006/geno.1993.1285.
A cDNA encoding human liver carboxylesterase and its gene were isolated. Nucleotide sequence analyses of the cDNA revealed that the predicted enzyme protein consists of 567 amino acids, including 18 amino acids of a putative signal peptide. Comparison of the deduced amino acid sequences of this enzyme with those of seven other carboxylesterases in various mammalian species, together with experimental data from several other laboratories, showed that these enzymes can be classified into three groups depending on the sequences at their carboxyl terminals and the presence or absence of one exon. A human carboxylesterase gene was found to span approximately 30 kb and to have 14 small exons. Alignments of this gene with those of human cholinesterase and rat cholesterol esterase indicated insertional sites at some introns and homologous amino acid sequences around them, although these genes have different numbers of exons. Thus the results supported the conclusion that these esterases evolved from a common ancestral gene.
分离出了编码人肝脏羧酸酯酶的cDNA及其基因。对该cDNA的核苷酸序列分析表明，预测的酶蛋白由567个氨基酸组成，包括一个推定信号肽的18个氨基酸。将该酶推导的氨基酸序列与各种哺乳动物物种中的其他七种羧酸酯酶的序列进行比较，以及来自其他几个实验室的实验数据表明，这些酶可根据其羧基末端的序列和一个外显子的有无分为三组。发现一个人羧酸酯酶基因跨度约为30kb，有14个小外显子。该基因与人胆碱酯酶和大鼠胆固醇酯酶的基因比对表明，尽管这些基因的外显子数量不同，但在一些内含子处有插入位点，且其周围有同源氨基酸序列。因此，结果支持了这些酯酶由一个共同祖先基因进化而来的结论。
