Abstract
Complete g -actin genes from Rhodeus notatus and Hypophthalmichthys molitrix (silver carp) were amplified by polymerase chain reaction and cloned into pCRII vector for further characterization. The g -actin genes of these two fishes were 1718 and 1755 bp in sequence length, respectively, and both of them contained 5 exons and 4 introns. The exon and intron boundaries were identified with the GT/AG rule. The phylogenetic implications of g -actin gene in the family Cyprinidae were shortly discussed.