MOLECULAR CLONING, TISSUE DISTRIBUTION OF ELOVL4, ELOVL5 AND ELOVL7 FROM ACIPENSER DABRYANUS

Long-chain polyunsaturated fatty acids (LC-PUFAs) are essential for numerous critical biological processes, and elongases of very long chain fatty acids are the rate-limiting enzyme for LC-PUFAs synthesis. The CDS of Elovl4, Elovl5 and Elovl7 were cloned from the unigene database by full-length transcriptome sequencing of A. dabryanus. Results showed that the open reading frames (ORF) of Elovl4, Elovl5 and Elovl7 were 753, 885 and 846 bp which encoded 250, 294 and 281-residue peptide, respectively. Phylogenetic analysis showed that the Elovl4, Elovl5 and Elovl7 clustered with Lepisosteus oculatus. Tissue expression analysis showed that the highest Elovl4 level was in the ovary and eye; muscle Elovl5 level was significantly higher than other tissues and the highest Elovl7 was in ovary, which was followed by gill and testis (P<0.05). Starvation significantly decreased the expression of liver Elovl4, Elovl5 and Elovl7 (P<0.05). Stomach Elovl4, Elovl5 and Elovl7 reduced significantly (P<0.05) at day 3, and then significantly upregulated. The highest expression levels of Elovl4, Elovl5 and Elovl7 in brain and muscle were at day 7, and then dropped dramatically (P<0.05). These findings suggest that Elovl4, Elovl5 and Elovl7 may play certain roles in the nutritional regulation of A. dabryanus, and the specific mechanisms need further investigation.