Heart and liver defects and reduced transforming growth factor β2 sensitivity in transforming growth factor β type III receptor-deficient embryos

Abstract

The type III transforming growth factor β (TGFβ) receptor (TβRIII) binds both TGFβ and inhibin with high affinity and modulates the association of these ligands with their signaling receptors. However, the significance of TβRIII signaling in vivo is not known. In this study, we have sought to determine the role of TβRIII during development. We identified the predominant expression sites of TβRIII mRNA as liver and heart during midgestation and have disrupted the murine TβRIII gene by homologous recombination. Beginning at embryonic day 13.5, mice with mutations in TβRIII developed lethal proliferative defects in heart and apoptosis in liver, indicating that TβRIII is required during murine s..