Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2004
Publication Date: 12/1/2004
Citation: Waldbieser, G.C., Bosworth, B.G. 2004. Cloning and characterization of myogenic regulatory genes in three Ictalurid catfish species. Animal Genetics 35:425-430. Interpretive Summary: Development of improved channel catfish germplasm with superior growth and meat yield will benefit catfish producers, processors, and consumers. Little information is known about the role of specific genes in the physiology of growth and meat yield in fish. We report sequence, mapping, and expression data for myogenin, MyoD, myostatin, and follistatin (genes demonstrated to affect muscle growth in mammals) for 3 catfish species: channel catfish (Ictalurus punctatus), blue catfish (I. furcatus), and white catfish (I. catus). Amino acid sequence and expression for the genes were generally similar to that observed for other fish and mammalian species. Information provided in this study is being used to study the molecular genetics and physiology of muscle growth and development in catfish.
Technical Abstract: A better understanding of the molecular genetics of muscle growth will be useful in developing catfish germplasm with improved growth and meat yield. We report sequence, tissue expression, and map-position data for myogenin, MyoD, myostatin, and follistatin in three Ictalurid catfish species: channel catfish (Ictalurus punctatus), blue catfish (I. furcatus), and white catfish (I. catus). These genes are involved in muscle growth and development in mammals and may play similar roles in muscle growth and development in catfish. Amino acid sequences were highly conserved among the three ictalurid species (> 95% identity), moderately conserved among catfish and zebrafish (~ 80% identity), and less conserved among catfish and humans (~ 40 - 60% identity) for all four genes. Gene structure (number of exons and introns and exon-intron boundaries) was conserved between catfish and other species for all genes. Myogenin and MyoD expression was limited to skeletal muscle in juvenile channel catfish. Myostatin was expressed in a variety of tissues in juvenile channel catfish, a pattern common in other fish species but contrasting with data from mammals where myostatin is primarily expressed in skeletal muscle. Follistatin was expressed in juvenile catfish heart, testes, and spleen. All four genes contained polymorphic microsatellite repeats in non-coding regions and linkage analysis based on inheritance of these microsatellite loci was used to place the genes on the channel catfish linkage map.