Smad ProteinsSignal TransductionSmad3 ProteinSmad4 ProteinSmad7 ProteinSmad1 ProteinProtein Sorting SignalsSmad5 ProteinMolecular Sequence DataAmino Acid SequenceSmad2 ProteinSmad8 ProteinMembrane ProteinsTransforming Growth Factor betaTrans-ActivatorsSmad Proteins, Receptor-RegulatedDNA-Binding ProteinsTransduction, GeneticPhosphorylationBone Morphogenetic ProteinsReceptors, Transforming Growth Factor betaCell LineActivinsSmad6 ProteinCells, CulturedProtein BindingSmad Proteins, InhibitoryBase SequenceTranscription, GeneticCOS CellsTransfectionTranscription FactorsTransforming Growth Factor beta1MutationActivin Receptors, Type IProtein-Serine-Threonine KinasesModels, BiologicalGene Expression RegulationRNA, MessengerRecombinant Fusion ProteinsProtein Structure, TertiaryPromoter Regions, GeneticBinding SitesTranscriptional ActivationMitogen-Activated Protein KinasesCell NucleusBlotting, WesternEnzyme ActivationPhosphoproteinsTumor Cells, CulturedGenes, ReporterBone Morphogenetic Protein 2Intracellular Signaling Peptides and ProteinsSequence Homology, Amino AcidProtein-Tyrosine KinasesProto-Oncogene ProteinsCell DivisionCell DifferentiationRecombinant ProteinsGene ExpressionTwo-Hybrid System TechniquesReverse Transcriptase Polymerase Chain ReactionActivin ReceptorsTyrosineBone Morphogenetic Protein Receptors, Type IActive Transport, Cell NucleusMinkLuciferasesXenopus ProteinsCloning, MolecularTime FactorsBone Morphogenetic Protein 4CalciumApoptosisLigandsProtein Kinase CProtein KinasesPrecipitin TestsCell Line, TumorCytoplasmGenetic VectorsAdaptor Proteins, Signal TransducingFollistatin-Related ProteinsEnzyme InhibitorsDNA, ComplementaryNuclear ProteinsFibroblastsDNAMice, Inbred C57BLGene Expression Regulation, DevelopmentalBacterial ProteinsFollicle Stimulating Hormone, beta SubunitProteinsInhibinsPlasmidsImmunoblottingReceptors, Cell SurfaceGTP-Binding ProteinsCell MembraneRepressor Proteins