Embryonic DevelopmentEmbryo, MammalianEmbryo, NonmammalianChick EmbryoGene Expression Regulation, DevelopmentalEmbryonic and Fetal DevelopmentBlastocystEmbryo ImplantationEmbryo LossZebrafishIn Situ HybridizationPregnancyZygoteFertilization in VitroOocytesBody PatterningZebrafish ProteinsMorphogenesisMolecular Sequence DataBlastomeresMesodermCleavage Stage, OvumGastrulaMorulaHomeodomain ProteinsTranscription FactorsCell DifferentiationRNA, MessengerBase SequenceAmino Acid SequenceXenopus ProteinsSignal TransductionEctodermNervous SystemPhenotypeGenes, LethalFertilizationDrosophila ProteinsDrosophilaMutationNuclear Transfer TechniquesEndodermMice, KnockoutCulture TechniquesGene TargetingParthenogenesisYolk SacEctogenesisCryopreservationOvumOrganogenesisXenopus laevisAnimals, Genetically ModifiedTime FactorsDevelopmental BiologySomitesEmbryonic Stem CellsEmbryo DispositionDNA-Binding ProteinsNeural CrestMice, Inbred C57BLOogenesisGastrulationXenopusDrosophila melanogasterDNA, ComplementaryImmunohistochemistryCloning, OrganismSequence Homology, Amino AcidSperm Injections, IntracytoplasmicMice, TransgenicEmbryonic InductionCloning, MolecularStem CellsWnt ProteinsGenes, HomeoboxCell LineageGene ExpressionMicroinjectionsReverse Transcriptase Polymerase Chain ReactionFetal ViabilityEmbryologyMice, Mutant StrainsHedgehog ProteinsBlastodermGerm LayersSea UrchinsMice, Inbred ICRChimeraCentral Nervous SystemEmbryo Culture TechniquesNotochordModels, BiologicalBone Morphogenetic ProteinsTranscription, GeneticNeural TubeCell MovementLarvaGestational AgeSpermatozoa