title: Expression pattern of mRNA A and mRNA B of alpha sarcoglycan gene during mouse embryonic development and regulation of their expression by myogenic and cardiogenic transcription factors.
abstract: BACKGROUND
  Type 2D limb-girdle muscular dystrophy (LGM2D) is a progressive disorder caused by mutations in the alpha sarcoglycan (α-SG) gene. In mice, the α-SG gene contains two promoters that regulate the expression of two different mRNAs (A and B). However, their gene expression pattern during embryonic development has not been explored and their regulation by myogenic and cardiogenic transcription factors has been only partially studied.
  
  
  RESULTS
  During embryonic development, mRNA A and B of α-SG gene were initially detected in hypaxial muscles, heart, stomach, tongue, and mesenchymal cells, which surround the dorsal region of the somites. Moreover, mRNA B was exclusively expressed in the floor plate and notochord and in the interdigits of limbs. In vitro, MyoD and myogenin positively regulated the transcription of mRNA B during skeletal myogenesis, whereas mRNA A was activated only for MyoD in differentiated skeletal muscle. In addition, Gata-4 together with Mef2c may regulate the expression of mRNA B in heart development, whereas Nkx2.5 and myocardin may activate expression of mRNA A in the differentiated cardiomyocyte.
  
  
  CONCLUSIONS
  The differential expression of α-SG mRNAs during mouse embryonic development may be a consequence of the differential regulation of both promoters by myogenic and cardiogenic factors.
authors.affiliation: División de Investigación Biomédica, Subdirección de Enseñanza e Investigación, Centro Médico Nacional 20 de Noviembre, Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado, México, D.F. México.
authors.forename: Bladimir
authors.initials: B
authors.lastname: Roque-Ramírez
authors.forename: Jesús
authors.initials: J
authors.lastname: Chimal-Monroy
authors.forename: Patricia
authors.initials: P
authors.lastname: Canto
authors.forename: Ramón Mauricio
authors.initials: RM
authors.lastname: Coral-Vázquez
mesh_terms: D000818:Animals; D047369:Chromatin Immunoprecipitation; D017931:DNA Primers / Q000235:genetics; D047108:Embryonic Development / Q000502:physiology*; D050991:GATA4 Transcription Factor; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D006321:Heart / Q000196:embryology; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; D017403:In Situ Hybridization; D008156:Luciferases; D064326:MEF2 Transcription Factors; D051379:Mice; D024510:Muscle Development / Q000502:physiology; D049288:Muscular Dystrophies, Limb-Girdle / Q000235:genetics*; D017570:MyoD Protein / Q000378:metabolism; D018008:Myogenin / Q000378:metabolism; D009687:Nuclear Proteins; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D049031:Sarcoglycans / Q000235:genetics / Q000378:metabolism*; D018709:Statistics, Nonparametric; D015534:Trans-Activators; D014157:Transcription Factors / Q000378:metabolism*; D000099251:Myocardin
chemical_list: D017931:DNA Primers; D050991:GATA4 Transcription Factor; D000072576:Homeobox Protein Nkx-2.5; D018398:Homeodomain Proteins; D008156:Luciferases; D064326:MEF2 Transcription Factors; D017570:MyoD Protein; D018008:Myogenin; D009687:Nuclear Proteins; D012333:RNA, Messenger; D049031:Sarcoglycans; D015534:Trans-Activators; D014157:Transcription Factors; D000099251:Myocardin; C484171:Gata4 protein, mouse; C578041:Mef2c protein, mouse; C057363:MyoD1 myogenic differentiation protein; C503801:Myog protein, mouse; C484469:Nkx2-5 protein, mouse
keywords: alpha sarcoglycan; cardiac muscle; embryonic development; gene expression; mouse; muscular dystrophy; skeletal muscle