title: Requirement of the transcription factor GATA4 for heart tube formation and ventral morphogenesis.
abstract: The zinc finger transcription factor GATA4 has been implicated in heart development based on its early expression in precardiogenic splanchnic mesoderm and its ability to activate the expression of a number of cardiac-specific genes. To determine the role of GATA4 in embryogenesis, we generated mice homozygous for a GATA4 null allele. Homozygous GATA4 null mice arrested in development between E7.0 and E9.5 because of severe developmental abnormalities. Mutant embryos most notably lacked a primitive heart tube and foregut and developed partially outside the yolk sac. In the mutants, the two bilaterally symmetric promyocardial primordia failed to migrate ventrally but instead remained lateral and generated two independent heart tubes that contained differentiated cardiomyocytes. We show that these deformities resulted from a general loss in lateral to ventral folding throughout the embryo. GATA4 is most highly expressed within the precardiogenic splanchnic mesoderm at the posterior lip of the anterior intestinal portal, corresponding to the region of the embryo that undergoes ventral fusion. We propose that GATA4 is required for the migration or folding morphogenesis of the precardiogenic splanchnic mesodermal cells at the level of the AIP.
authors.affiliation: Department of Molecular Biology and Oncology, University of Texas Southwestern Medical Center at Dallas, 75235-9148, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Molkentin
authors.forename: Q
authors.initials: Q
authors.lastname: Lin
authors.forename: S A
authors.initials: SA
authors.lastname: Duncan
authors.forename: E N
authors.initials: EN
authors.lastname: Olson
mesh_terms: D000818:Animals; D019521:Body Patterning; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004064:Digestive System / Q000737:chemistry / Q000196:embryology; D005314:Embryonic and Fetal Development; D050991:GATA4 Transcription Factor; D050992:GATA5 Transcription Factor; D050993:GATA6 Transcription Factor; D005775:Gastrula; D018507:Gene Expression Regulation, Developmental; D006321:Heart / Q000196:embryology*; D051379:Mice; D008817:Mice, Mutant Strains; D009024:Morphogenesis; D009206:Myocardium / Q000737:chemistry / Q000166:cytology; D009420:Nervous System / Q000737:chemistry / Q000196:embryology; D012333:RNA, Messenger / Q000032:analysis; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D015017:Yolk Sac / Q000196:embryology
chemical_list: D004268:DNA-Binding Proteins; D050991:GATA4 Transcription Factor; D050992:GATA5 Transcription Factor; D050993:GATA6 Transcription Factor; C494756:Gata5 protein, mouse; D012333:RNA, Messenger; D014157:Transcription Factors