Organizers, EmbryonicNucleolus Organizer RegionGoosecoid ProteinXenopus ProteinsGastrulaEmbryonic InductionBody PatterningGene Expression Regulation, DevelopmentalXenopusEmbryo, NonmammalianMesodermEmbryonic DevelopmentZebrafish ProteinsXenopus laevisHomeodomain ProteinsNodal ProteinEctodermIntercellular Signaling Peptides and ProteinsIn Situ HybridizationEmbryologyBone Morphogenetic ProteinsWnt ProteinsMorphogenesisSilver StainingActivinsBone Morphogenetic Protein 4ProteinsSignal TransductionMolecular Sequence DataOtx Transcription FactorsTranscription FactorsT-Box Domain ProteinsZebrafishMicroinjectionsTransforming Growth Factor betaGlycoproteinsNervous SystemAmino Acid SequenceFibroblast Growth Factor 8RhombencephalonNotochordRepressor ProteinsGenes, HomeoboxMesencephalonHydraSequence Homology, Amino AcidNodal Signaling LigandsRNA, MessengerHeadBase SequenceAxisEmbryonic and Fetal DevelopmentTissue TransplantationCarrier ProteinsAmphibiansLIM-Homeodomain ProteinsEmbryo, MammalianBlastocystChick EmbryoEndodermCell NucleolusSilverBlastulaWnt1 ProteinFetal ProteinsInhibinsLeft-Right Determination FactorsTrans-ActivatorsDNA-Binding ProteinsFibroblast Growth FactorsBlastodermMetencephalonCell DifferentiationZygotebeta CateninHedgehog ProteinsTwins, ConjoinedCytoskeletal ProteinsCentral Nervous SystemCloning, MolecularBlastomeresBone Morphogenetic Protein 7MutationMatrix Attachment Region Binding ProteinsNerve Tissue ProteinsDrosophila ProteinsHepatocyte Nuclear Factor 3-betaDrosophilaSilver NitratePhenotypeDevelopmental BiologySomitesGenes, DevelopmentalCell LineageNeural PlateEmbryo LossNeural TubeProsencephalonAnimals, Genetically ModifiedModels, Biological