A novel salmonid myoD gene is distinctly regulated during development and probably arose by duplication after the genome tetraploidization.
A novel myoD paralogue was characterised in Salmo salar (smyoD1c) and S. trutta (btmyoD1c). SmyoD1c had 78.2/90.6% protein sequence identity to smyoD1a/smyoD1b, respectively. Each paralogue was differentially expressed throughout somitogenesis. In adult fish, smyoD1a was the predominant gene expressed in fast muscle, whereas smyoD1c was 2-3 times upregulated in slow muscle compared to smyoD1a/1b. A maximum likelihood analysis indicated that myoD1c arose by duplication of myoD1b after the salmonid tetraploidization. Another myoD paralogue (myoD2) is present in at least some teleosts, reflecting a more ancient genome duplication. To accommodate these findings we propose a simplified teleost-myoD nomenclature.
Macqueen
Daniel J
DJ
Gatty Marine Laboratory, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB Scotland, UK.
Johnston
Ian A
IA
D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation; D004625:Embryo, Nonmammalian / Q000166:cytology; D019143:Evolution, Molecular; D020440:Gene Duplication; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D016678:Genome / Q000235:genetics*; D016013:Likelihood Functions; D008969:Molecular Sequence Data; D018656:Muscle Fibers, Fast-Twitch / Q000166:cytology; D018657:Muscle Fibers, Slow-Twitch / Q000166:cytology; D017570:MyoD Protein / Q000737:chemistry / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011123:Polyploidy; D012487:Salmonidae / Q000196:embryology / Q000235:genetics*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
D017570:MyoD Protein