title: Identification of an essential nonneuronal function of neurotrophin 3 in mammalian cardiac development.
abstract: Neurotrophin 3 (Nt3) is one of five neurotrophin growth factors which shape the development of the nervous system by regulating neuronal survival and differentiation. Peripheral neuronal subpopulations expressing the TrkC receptor tyrosine kinase respond to Nt3 with enhanced survival, mitogenesis or cell migration and these neurons are lost in homozygous Nt3 null (-/-) mutant mice. The unexplained perinatal lethality in the Nt3-/- mice, however, suggests a wider function for this neurotrophin. Here we report that Nt3 is essential for the normal development of atria, ventricles, and cardiac outflow tracts. Histological and echocardiographic image analysis of Nt3-/- animals reveal severe cardiovascular abnormalities including atrial and ventricular septal defects, and tetralogy of Fallot, resembling some of the most common congenital malformations in humans. The observed defects are consistent with abnormalities in the survival and/or migration of cardiac neural crest early in embryogenesis and establish an essential role for neurotrophin 3 in regulating the development of the mammalian heart.
authors.affiliation: Department of Pathology, Children's Hospital, Boston, Massachusetts 02115, USA.
authors.forename: M J
authors.initials: MJ
authors.lastname: Donovan
authors.forename: R
authors.initials: R
authors.lastname: Hahn
authors.forename: L
authors.initials: L
authors.lastname: Tessarollo
authors.forename: B L
authors.initials: BL
authors.lastname: Hempstead
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000831:Animals, Newborn; D004452:Echocardiography; D005314:Embryonic and Fetal Development; D006321:Heart / Q000196:embryology* / Q000254:growth & development* / Q000503:physiopathology; D006330:Heart Defects, Congenital / Q000000981:diagnostic imaging / Q000196:embryology* / Q000473:pathology; D051379:Mice; D008817:Mice, Mutant Strains; D008969:Molecular Sequence Data; D009206:Myocardium / Q000737:chemistry / Q000473:pathology; D009414:Nerve Growth Factors / Q000502:physiology*; D009432:Neural Crest; D020933:Neurotrophin 3; D020794:Receptor Protein-Tyrosine Kinases / Q000032:analysis; D020812:Receptor, trkC; D017475:Receptors, Nerve Growth Factor / Q000032:analysis
chemical_list: D009414:Nerve Growth Factors; D020933:Neurotrophin 3; D017475:Receptors, Nerve Growth Factor; D020794:Receptor Protein-Tyrosine Kinases; D020812:Receptor, trkC