Sea UrchinsEmbryo, NonmammalianCell DifferentiationMesodermStrongylocentrotus purpuratusLytechinusGene Expression Regulation, DevelopmentalEctodermEmbryo, MammalianChick EmbryoGastrulaHemicentrotusParacentrotusOvumMorphogenesisBlastomeresEndodermIn Situ HybridizationEmbryonic DevelopmentBody PatterningBlastulaBlastocystMolecular Sequence DataNodal ProteinTranscription FactorsRNA, MessengerEmbryonic InductionFertilizationSignal TransductionBase SequenceHomeodomain ProteinsEchinodermataCell LineageBone Morphogenetic ProteinsAmino Acid SequenceEmbryo ImplantationEmbryonic and Fetal DevelopmentMicroinjectionsZygoteCleavage Stage, OvumCell DivisionStem CellsHyalinCells, CulturedDNA-Binding ProteinsTranscription, GeneticOdontogenesisGene Expression RegulationEpitheliumModels, BiologicalTrans-ActivatorsCloning, MolecularToothGene ExpressionUreterTime FactorsLimb BudsWnt ProteinsExtremitiesGastrulationSequence Homology, Amino AcidBone Morphogenetic Protein 4Larvabeta CateninImmunohistochemistryPregnancyNeural CrestCell LineReceptors, NotchTretinoinDNA, ComplementaryMSX1 Transcription FactorEmbryonic Stem CellsPhenotypeMice, TransgenicOrgan Culture TechniquesHedgehog ProteinsDNADNA PrimersOligonucleotides, AntisenseSex DifferentiationCytoskeletal ProteinsMice, KnockoutOligoribonucleotides, AntisenseProteinsCell NucleusGene Regulatory NetworksFibroblast Growth FactorsMice, Inbred C57BLTransforming Growth Factor betaCell ProliferationReverse Transcriptase Polymerase Chain ReactionStarfishZebrafishEmbryo LossEmetineFibroblast Growth Factor 9QuailFluorescent Antibody TechniqueOocytes