Structure of the rat pancreatic cholesterol esterase gene.
Structure of the rat pancreatic cholesterol esterase gene.
复制标题
大鼠胰腺胆固醇酯酶基因的结构。
DOI：
10.1021/bi00242a028
复制
发表时间：
1991
期刊：
影响因子：
2.9
通讯作者：
Hui,DY
中科院分区：
文献类型：
--
作者：
Fontaine,RN;Carter,CP;Hui,DY
辛辛那提大学医学院病理学和实验医学系，俄亥俄州辛辛那提 45267-0529 1990 年 11 月 21 日收稿；修订稿于 1991 年 5 月 9 日收到摘要：编码大鼠胰腺胆固醇酯酶的基因已被分离和表征。对重叠基因组克隆的分析表明，胆固醇酯酶基因的长度约为 8 kb，包含 11 个被 10 个内含子中断的外显子。除最后一个外显子长度为 548 bp 外，外显子的大小范围为 83 至 201 bp。 TAAATA 序列存在于距转录起始位点约 31 个核苷酸处。在 CAP 位点上游 90 bp 处发现了假定的胰腺特异性增强子序列。尽管胆固醇酯酶与胆碱酯酶和乙酰胆碱酯酶具有三个相似的结构域，但发现这些结构域位于胆固醇酯酶基因的不同外显子中。胆固醇酯酶基因的组织表明其与丝氨酸酯酶基因家族的其他成员的进化不同。胰腺胆固醇酯酶，也称为羧基酯脂肪酶、胆盐刺激脂肪酶或非特异性脂肪酶，催化胆固醇酯水解成游离胆固醇和脂肪酸。该酶在胰腺的腺泡细胞中合成，并通过胰管释放到肠腔中（Guy & Figarella，1981）。胆固醇酯酶是胰液中最丰富的蛋白质之一（Rudd & Brockman，1984）。目前来自多个实验室的数据（Gallo 等人，1984 年；Williams 等人，1989 年）表明胆固醇酯酶在介导肠道胆固醇吸收中发挥着作用。胆固醇酯酶也已被证明与胰脂肪酶在脂质吸收中协同作用（Lindstrom 等，1988）。此外，胆固醇酯酶是胰液中唯一能够水解维生素酯的酶（Rudd & Brockman，1984），这表明它在催化饮食中脂溶性维生素的淋巴吸收方面发挥着作用。鉴于胆固醇吸收的速率和效率可能是 f 的重要决定因素，这项研究得到了美国国立卫生研究院 Grant DK 40917 的支持。
Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0529 Received November 21, 1990; Revised Manuscript Received May 9, 1991 abstract: The gene encoding the rat pancreatic cholesterol esterase has been isolated and characterized. Analysis of overlapping genomicclones showed that the cholesterol esterase genespans approximately 8 kb, containing 11 exons interrupted by 10 introns. The exons ranged in size from 83 to 201 bp except for the last exon, which was 548 bp in length. A TAAATA sequence was present at-31 nucleotides from the transcriptional initiation site. A putative pancreas-specific enhancer sequence was found at-90 bp upstream from the CAP site. Although cholesterol esterase shares three domains of similarity with cholinesterase and acetylcholinesterase, these domains were found to be localized in distinct exons of the cholesterol esterase gene. The organization of the cholesterol esterase gene suggests its divergent evolution with othermembers of the serine esterase gene family. e cholesterol esterase of the pancreas, also called carboxyl ester lipase, bile salt stimulated lipase, or nonspecific lipase, catalyzes the hydrolysis of cholesteryl esters to free cholesterol and fatty acids. The enzyme is synthesized in the acinar cells of the pancreas and is released into the intestinal lumen via the pancreatic duct (Guy & Figarella, 1981). The cholesterol esterase isone of the most abundant proteins in the pancreatic juice (Rudd & Brockman, 1984). Current data from several laboratories (Gallo et al., 1984; Williams et al., 1989) have suggested a role of the cholesterol esterase in mediating cholesterol absorption in the gut. The cholesterol esterasehas also been shownto act in concert with pancreatic lipase in lipid absorption (Lindstrom et al., 1988). In addition, the cholesterol esterase is the only enzyme in the pancreatic juice capable of hydrolyzing vitamin esters (Rudd & Brockman, 1984), suggesting its role in catalyzing the lymphatic absorption of fat-soluble vitamins from the diet. In view of observations that the rate and efficiency of cholesterol absorption may be important determinants in fThis research was supported by Grant DK 40917 from the National Institutes of Health.