Zebrafish cDNA encoding multifunctional fatty acid elongase involved in production of eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acids
Zebrafish cDNA encoding multifunctional fatty acid elongase involved in production of eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acids
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DOI：
10.1007/s10126-003-0029-1
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发表时间：
2004-05-01
影响因子：
3
通讯作者：
Teale, AJ
中科院分区：
文献类型：
--
作者：
Agaba, M;Tocher, DR;Teale, AJ
增加脂肪酸链长的酶对于高度不饱和脂肪酸的生物合成是必不可少的。GLELO基因编码一种蛋白质，参与真菌高山被孢霉中多不饱和脂肪酸的伸长。对GenBank数据库的搜索发现了几个表达序列标签序列，包括从斑马鱼(Danio Rerio)获得的与gLELO高度相似的序列标签序列。ZfELO全长转录本，编码291个氨基酸残基的多肽，是从斑马鱼肝脏cDNA中分离得到的。预测的开放阅读框的氨基酸序列与秀丽线虫和人的伸长高度相似。当在酿酒酵母中表达时，斑马鱼开放阅读框架能够延长一系列C-18、C-20和C-22多不饱和脂肪酸的链，这不仅表明通过24碳中间体从18：3N-3生物合成22：6N-3是可行的，而且一个伸长酶可以完成所需的所有三个延伸步骤。斑马鱼酶还能够拉长单不饱和脂肪酸和饱和脂肪酸，因此在底物使用方面表现出比之前描述的任何伸长酶更大的混杂程度。
Enzymes that increase the chain length of fatty acids are essential for biosynthesis of highly unsaturated fatty acids. The gLELO gene encodes a protein involved in the elongation of polyunsaturated fatty acids in the fungus Mortierella alpina. A search of the GenBank database identified several expressed sequence tag sequences, including one obtained from zebrafish (Danio rerio), with high similarity to gLELO. The full-length transcript ZfELO, encoding a polypeptide of 291 amino acid residues, was isolated from zebrafish liver cDNA. The predicted amino acid sequence of the open reading frame shared high similarity with the elongases of Caenorhabditis elegans and human. When expressed in Saccharomyces cerevisiae, the zebrafish open reading frame conferred the ability to lengthen the chain of a range of C-18, C-20, and C-22 polyunsaturated fatty acids, indicating not only that biosynthesis of 22:6n-3 from 18:3n-3 via a 24-carbon intermediate is feasible, but also that one elongase enzyme can perform all three elongation steps required. The zebrafish enzyme was also able to elongate monounsaturated and saturated fatty acids, and thus demonstrates a greater level of promiscuity in terms of substrate use than any elongase enzyme described previously.