Guangdong Provincial Key Laboratory of Marine Biology, Shantou University, Shantou 515063, China.
College of Marine Science, South China Agriculture University, Guangzhou 510642, China.
Gene. 2018 Jun 15;659:11-21. doi: 10.1016/j.gene.2018.03.046. Epub 2018 Mar 16.
Enzymes that lengthen the carbon chain of polyunsaturated fatty acids (PUFA) are key to the biosynthesis of the long-chain polyunsaturated fatty acids (LC-PUFA). Here we report on the molecular cloning, tissue distribution, functional characterization and nutritional regulation of a elovl5 gene from Nibea coibor. The full-length cDNA was 1315 bp, including a 5-untranslated region (UTR) of 134 bp, a 3-UTR of 296 bp and an open reading frame of 885 bp, which specified a peptide of 294 amino acids. Bioinformatics analysis showed that the deduced peptide sequence possessed all the characteristic features of microsomal fatty acyl elongases, including the so-called histidine box (HXXHH), the canonical C-terminal endoplasmic reticulum retention signal, several predicted transmembrane regions and other highly conserved motifs. Expression of elovl5 was strongly observed in stomach, and more weakly in kidney, spleen, intestine, brain, eye, liver, gill, muscle and heart. Functional characterization revealed that the chu's croaker Elovl5 was able to elongate both C18 and C20 PUFA substrates. Nutritional study indicated that the hepatic expression of elovl5 could be up-regulated by low dietary n-3 LC-PUFA. These results may contribute to better understanding the LC-PUFA biosynthetic pathway and regulation mechanism in chu's croaker.
延长多不饱和脂肪酸（PUFA）碳链的酶是长链多不饱和脂肪酸（LC-PUFA）生物合成的关键。在这里，我们报告了来自 Nibea coibor 的 elovl5 基因的分子克隆、组织分布、功能特征和营养调节。全长 cDNA 为 1315bp，包括 134bp 的 5'非翻译区（UTR）、296bp 的 3'UTR 和 885bp 的开放阅读框，指定了 294 个氨基酸的肽。生物信息学分析表明，推导的肽序列具有微粒体脂肪酸延伸酶的所有特征，包括所谓的组氨酸盒（HXXHH）、典型的内质网保留信号的 C 末端、几个预测的跨膜区域和其他高度保守的基序。elovl5 的表达在胃中强烈观察到，在肾脏、脾脏、肠、脑、眼、肝脏、鳃、肌肉和心脏中较弱。功能特征表明，楚氏黄鱼 Elovl5 能够延长 C18 和 C20 PUFA 底物。营养研究表明，低膳食 n-3 LC-PUFA 可上调肝脏中 elovl5 的表达。这些结果可能有助于更好地理解楚氏黄鱼 LC-PUFA 生物合成途径和调节机制。
