The partial cDNA of peroxisome proliferator activated receptorgamma coactivator1 alpha(PGC-1α)was cloned(GenBank accession number HM015283),and the homologous alignment was analyzed.The expression in different organs of PGC-1α was detected in grass carp with the methods of qRT-PCR.The influence of dietary highly unsaturated fatty acids(HUFAs)on the temporal expression of PGC-1α in hepatopancreas of grass carp was also studied.The results showed that the obtained cDNA sequence was 612 bp in length,and its homology with human,cow,mice,zebra fish and other species is 75%-97%; and it is revealed that PGC-1α is widely expressed in hepatopancreas,kidney,muscle,heart,gill,and so on,with the highest expression level observed in kidney and heart,lowest in spermary and spleen.After six days feeding with HUFAs contained diet,the expression level of PGC-1α was significantly increased,then descended quickly in the following days.Our results indicate that PGC-1α is mainly express in high energy generating tissues and its expression level described as could be regulated by HUFAs.The expression pattern of PGC-1α induced by dietary HUFAs could be rising at first then going down back to the normal level.