MorphogenesisCell DifferentiationEmbryo, NonmammalianEmbryo, MammalianGene Expression Regulation, DevelopmentalChick EmbryoEmbryonic DevelopmentBlastocystIn Situ HybridizationMesodermBody PatterningSignal TransductionTranscription FactorsMolecular Sequence DataEmbryonic and Fetal DevelopmentHomeodomain ProteinsZebrafishEmbryo ImplantationDrosophila ProteinsMutationPhenotypeRNA, MessengerCells, CulturedZygoteBase SequenceDrosophilaAmino Acid SequenceEpitheliumCell DivisionStem CellsZebrafish ProteinsGastrulaPregnancyBlastomeresCell LineageModels, BiologicalCell PolarityCell LineEpithelial CellsOocytesEctodermDNA-Binding ProteinsImmunohistochemistryOrganogenesisEndodermCleavage Stage, OvumAnimals, Genetically ModifiedBone Morphogenetic ProteinsXenopus ProteinsMice, TransgenicEmbryo LossMice, KnockoutEmbryonic Stem CellsDrosophila melanogasterCell ProliferationCaenorhabditis elegansGene ExpressionCell MovementReverse Transcriptase Polymerase Chain ReactionMice, Inbred C57BLTime FactorsGene Expression RegulationCaenorhabditis elegans ProteinsEmbryonic InductionOrgan Culture TechniquesUreterTrans-ActivatorsMembrane ProteinsWnt ProteinsCell ShapeEpidermisFertilization in VitroTranscription, GeneticSequence Homology, Amino AcidTretinoinOogenesisFibroblast Growth FactorsXenopus laevisDNA PrimersActinsSex DifferentiationNervous SystemMicroscopy, ElectronExtremitiesRepressor ProteinsNerve Tissue ProteinsHedgehog ProteinsBone Morphogenetic Protein 4Neural CrestCadherinsGenes, InsectCulture TechniquesNuclear ProteinsGenes, HomeoboxCloning, MolecularMorulaFibroblast Growth Factor 10NotochordCell AdhesionGerm Cells