Anterior endoderm is sufficient to rescue foregut apoptosis and heart tube morphogenesis in an embryo lacking retinoic acid.
The vitamin A deficient (VAD) quail embryo lacks active retinoids, fails to express normally GATA-4, and develops a nonlooping heart tube morphogenetic defect that is a model for congenital cardiomyopathy. VAD quail embryos, or chick embryos depleted specifically for GATA factors, show in addition abnormal foregut development, characterized by apoptosis of the endoderm cells associated with presumptive myocardium during the process of heart tube formation. Exogenous retinoic acid or transplantation of normal chick embryo anterior endoderm is sufficient to rescue apoptosis as well as GATA-4 expression and results in normal development and heart tube morphogenesis. Normal posterior endoderm also contains retinoids but is unable to rescue the VAD defect. Our results indicate that a retinoid-dependent transcriptional program, mediated at least in part by GATA factors, is critical in presumptive foregut endoderm for normal heart tube morphogenesis.
Ghatpande
S
S
Department of Developmental Biology, Albert Einstein College of Medicine, Bronx, New York, 10461, USA.
Ghatpande
A
A
Zile
M
M
Evans
T
T
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002642:Chick Embryo; D002678:Chimera; D004268:DNA-Binding Proteins / Q000235:genetics; D004064:Digestive System / Q000166:cytology / Q000196:embryology*; D004707:Endoderm / Q000637:transplantation*; D050991:GATA4 Transcription Factor; D050992:GATA5 Transcription Factor; D050993:GATA6 Transcription Factor; D015870:Gene Expression; D006321:Heart / Q000196:embryology*; D006330:Heart Defects, Congenital / Q000196:embryology; D017403:In Situ Hybridization; D010641:Phenotype; D011784:Quail / Q000196:embryology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics; D014183:Transplantation, Heterologous; D014212:Tretinoin / Q000494:pharmacology; D014802:Vitamin A Deficiency / Q000196:embryology*
D004268:DNA-Binding Proteins; D050991:GATA4 Transcription Factor; D050992:GATA5 Transcription Factor; D050993:GATA6 Transcription Factor; D012333:RNA, Messenger; D014157:Transcription Factors; D014212:Tretinoin