MesodermFetal ProteinsGastrulaGastrulationCell DifferentiationT-Box Domain ProteinsGene Expression Regulation, DevelopmentalEmbryo, NonmammalianBody PatterningEctodermEmbryonic InductionXenopus ProteinsIn Situ HybridizationMorphogenesisZebrafish ProteinsZebrafishSomitesHomeodomain ProteinsTranscription FactorsSignal TransductionXenopusBone Morphogenetic ProteinsEndodermXenopus laevisNodal ProteinChick EmbryoMolecular Sequence DataCell LineageWnt ProteinsGerm LayersActivinsEmbryonic DevelopmentNervous SystemGoosecoid ProteinStem CellsBone Morphogenetic Protein 4Primitive StreakBlastulaRNA, MessengerDNA-Binding ProteinsEmbryonic and Fetal DevelopmentFibroblast Growth FactorsBase SequenceCell MovementGenes, HomeoboxCells, CulturedEmbryonic Stem CellsBlastodermEmbryo, MammalianAmino Acid SequenceDrosophila ProteinsPhenotypeDrosophilaNodal Signaling LigandsTrans-ActivatorsQuailNotochordTretinoinTransforming Growth Factor betaGene ExpressionCoturnixMutationModels, BiologicalCell LineNeural CrestBasic Helix-Loop-Helix Transcription FactorsCell DivisionImmunohistochemistryPleurodelesProteinsReverse Transcriptase Polymerase Chain ReactionHeadTailGene Expression RegulationTwist Transcription FactorLeft-Right Determination FactorsFibroblast Growth Factor 8Repressor ProteinsSequence Homology, Amino AcidIntercellular Signaling Peptides and ProteinsAvian ProteinsOrganizers, EmbryonicAnimals, Genetically ModifiedDNA PrimersSex DifferentiationCell ProliferationTranscription, GeneticSea UrchinsTime FactorsBlastomeresMice, KnockoutBlastocystMice, TransgenicInhibinsMyoD ProteinNuclear ProteinsCentral Nervous SystemBone Morphogenetic Protein 2Muscle DevelopmentCloning, Molecular