Characterization and Expression Analysis of Myogenin Gene in White Muscle of Chinese Mandarin Fish, Siniperca chuatsi

Myogenin plays a crucial role in myoblast differentiation and maturation. In the present study, the myogenin gene structure and expressional patterns in Siniperca chuatsi were characterized. Sequence analysis indicated that the myogenin shared a similar structure and the conserved bHLH domain with other vertebrate myogenin genes. Sequence alignment and phylogenetic analysis showed that Siniperca chuatsi myogenin shared homologous with Epinephelus coioides, Sparus aurata, Takifugu rubripes and Salmo salar. Whole-mount in situ hybridization revealed that myogenin expression was first detected in the gastrula stage embryos and high levels of expression at the 24 somite stage. After the 24 somite stage, myogenin expression began to decrease in the anterior somites where somatic cells were differentiated. Further, the muscle structural gene, MyHC, and myogenin, are concomitantly expressed during S. chuatsi embryonic development as assayed with whole-mount in situ hybridization. In the adult fish, the myogenin showed the highest levels of expression in the brain compared with the kidney, spleen, liver, heart and white muscles. Our work on the myogenin gene from the mandarin fish has provided useful information for fish molecular biology and fish genomics.