Activin Receptors, Type IIActivin ReceptorsActivinsActivin Receptors, Type IMyostatinReceptors, Transforming Growth Factor betaReceptors, Interleukin-1 Type IIInhibinsInhibin-beta SubunitsFollistatinBone Morphogenetic Protein Receptors, Type IIReceptors, Growth FactorTransforming Growth Factor betaProtein-Serine-Threonine KinasesSmad2 ProteinSignal TransductionSmad ProteinsProtein SubunitsBone Morphogenetic ProteinsReceptors, Interleukin-1RNA, MessengerReceptors, Tumor Necrosis Factor, Type II