title: Isolation and characterization of an avian slow myosin heavy chain gene expressed during embryonic skeletal muscle fiber formation.
abstract: We have isolated and begun characterization of the quail slow myosin heavy chain (MyHC) 3 gene, the first reported avian slow MyHC gene. Expression of slow MyHC 3 in skeletal muscle is restricted to the embryonic period of development, when the fiber pattern of future fast and slow muscle is established. In embryonic hindlimb development, slow MyHC 3 gene expression coincides with slow muscle fiber formation as distinguished by slow MyHC-specific antibody staining. In addition to expression in embryonic appendicular muscle, slow MyHC 3 is expressed continuously in the atria. Transfection of slow MyHC 3 promoter-reporter constructs into embryonic myoblasts that form slow MyHC-expressing fibers identified two regions regulating expression of this gene in skeletal muscle. The proximal promoter, containing potential muscle-specific regulatory motifs, permits expression of a reporter gene in embryonic slow muscle fibers, while a distal element, located greater than 2600 base pairs upstream, further enhances expression 3-fold. The slow muscle fiber-restricted expression of slow MyHC 3 during embryonic development, and expression of slow MyHC 3 promoter-reporter constructs in embryonic muscle fibers in vitro, makes this gene a useful marker to study the mechanism establishing the slow fiber lineage in the embryo.
authors.affiliation: Department of Medicine, Stanford University School of Medicine, Stanford, California 94305-5306, USA.
authors.forename: W
authors.initials: W
authors.lastname: Nikovits
authors.forename: G F
authors.initials: GF
authors.lastname: Wang
authors.forename: J L
authors.initials: JL
authors.lastname: Feldman
authors.forename: J B
authors.initials: JB
authors.lastname: Miller
authors.forename: R
authors.initials: R
authors.lastname: Wade
authors.forename: L
authors.initials: L
authors.lastname: Nelson
authors.forename: F E
authors.initials: FE
authors.lastname: Stockdale
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002642:Chick Embryo; D002645:Chickens; D003001:Cloning, Molecular; D004625:Embryo, Nonmammalian / Q000502:physiology*; D005091:Exons; D018507:Gene Expression Regulation, Developmental; D015698:Genomic Library; D006321:Heart / Q000196:embryology; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D018656:Muscle Fibers, Fast-Twitch / Q000502:physiology*; D018657:Muscle Fibers, Slow-Twitch / Q000502:physiology*; D018482:Muscle, Skeletal / Q000196:embryology* / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000096:biosynthesis* / Q000235:genetics*; D009838:Oligodeoxyribonucleotides; D011401:Promoter Regions, Genetic; D011784:Quail; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic
chemical_list: D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D018995:Myosin Heavy Chains