Organizers, EmbryonicGoosecoid ProteinNucleolus Organizer RegionXenopus ProteinsGastrulaEmbryonic InductionBody PatterningXenopusMesodermEmbryo, NonmammalianGene Expression Regulation, DevelopmentalXenopus laevisNodal ProteinZebrafish ProteinsHomeodomain ProteinsIntercellular Signaling Peptides and ProteinsEctodermBone Morphogenetic ProteinsEmbryologyIn Situ HybridizationWnt ProteinsBone Morphogenetic Protein 4ActivinsMorphogenesisProteinsSilver StainingMicroinjectionsT-Box Domain ProteinsTransforming Growth Factor betaGlycoproteinsSignal TransductionMolecular Sequence DataOtx Transcription FactorsTranscription FactorsRepressor ProteinsAmino Acid SequenceNervous SystemFibroblast Growth Factor 8Sequence Homology, Amino AcidRhombencephalonAmphibiansNotochordCarrier ProteinsHydraGenes, HomeoboxMesencephalonAxisNodal Signaling LigandsZebrafishRNA, MessengerBase SequenceHeadTissue TransplantationLIM-Homeodomain ProteinsInhibinsSilverCell NucleolusWnt1 ProteinLeft-Right Determination FactorsEndodermMetencephalonBlastulaBone Morphogenetic Protein 7Fetal ProteinsTrans-ActivatorsTwins, ConjoinedFibroblast Growth FactorsCytoskeletal ProteinsBlastodermMatrix Attachment Region Binding ProteinsDNA-Binding ProteinsChick EmbryoSilver Nitratebeta CateninHepatocyte Nuclear Factor 3-betaTectum MesencephaliNeural PlateDrug PackagingHedgehog ProteinsProsencephalonCloning, MolecularChromosomes