Signal transduction
NOTCH Activation Promotes Valve Formation by Regulating the Endocardial SecretomeThe NOTCH-dependent endocardial secretome has been determined by quantitative MS-based proteomics of mouse embryonic endocardial cells (MEEC). DLL4-mediated NOTCH activation lead to expression of EMT, cytoskeleton and cell-cell/cell-matrix proteins, whereas JAG1-NOTCH signaling activated ECM molecules expression. Data validation in vitro and in vivo support the value of MEEC as a model for studying the endocardial secretome and for the identification of novel factors potentially involved in heart development and disease.