Transcription Factor TFIIIARNA, Ribosomal, 5STranscription FactorsXenopus laevisRNA, RibosomalTranscription, GeneticPromoter Regions, GeneticDNA-Binding ProteinsMolecular Sequence DataBase SequenceSp1 Transcription FactorGene Expression RegulationBinding SitesZinc FingersProtein BindingTranscriptional ActivationTrans-ActivatorsRNA, MessengerDNABasic Helix-Loop-Helix Transcription FactorsMedical ErrorsNuclear ProteinsTranscription Factor AP-1Repressor ProteinsCell LineHomeodomain ProteinsGene Expression Regulation, DevelopmentalSignal TransductionMutationBasic-Leucine Zipper Transcription FactorsCell NucleusTranscription Factor AP-2Cell DifferentiationXenopusTransfection