This trial was conducted to investigate the role of the elovl1 gene from loach (Misgurnus anguillicaudatus).The loach elovl1 was cloned by using RT-PCR and RACE,and its expression patterns were analyzed.The loach were exposed to 8℃ and 26℃ for 30 d to evaluate the effects of cold stress on fatty acid composition,tissue morphology and expression of the elovl1 gene. The results showed that the elovl1a full-length cDNA was 2 216 bp with an ORF of 948 bp,encoding 315 amino acids and the elovl1b full-length cDNA was 1 895 bp with an ORF of 963 bp,encoding 320 amino acids.The elovl1 protein was conserved in vertebrates,containing one conserved diagnostic histidine box HXXHH motif,several transmembrane regions,and the endoplasmic reticulum retrieval signal (KXKXX) at the carboxyl terminus.The elovl1a and elovl1b were expressed in almost all tissues and the expression of elovl1a was lower than that of elovl1b in every tissue tested.Total saturated fatty acids (SFA) significantly decreased (P<0.05),and total monounsaturated fatty acids (MUFA) significantly increased in the liver at 8℃ compared to that at 26℃ (P<0.05).Both elovl1a and elovl1b were significantly induced in the muscle and liver (P<0.05) after exposed to cold.In conclusion,elovl1 was conserved in vertebrates,which might involve in energy production and play an important role in adaptation to cold temperature.