Matrix Attachment Region Binding ProteinsBinding SitesMolecular Sequence DataDNA-Binding ProteinsBase SequenceProtein BindingAmino Acid SequencePromoter Regions, GeneticBinding, CompetitiveModels, MolecularTranscription FactorsKineticsProtein ConformationMutagenesis, Site-DirectedProtein Structure, TertiaryTranscription, GeneticCell LineLigandsMutationDNAStructure-Activity RelationshipRecombinant ProteinsEscherichia coliBinding Sites, AntibodyCrystallography, X-RayGene Expression RegulationEnhancer Elements, GeneticConsensus SequenceSequence Homology, Amino AcidSp1 Transcription FactorRegulatory Sequences, Nucleic AcidSequence AlignmentDNA FootprintingTransfectionRadioligand Assay