title: Redox state of p63 and p73 core domains regulates sequence-specific DNA binding.
abstract: Cysteine oxidation and covalent modification of redox sensitive transcription factors including p53 are known, among others, as important events in cell response to oxidative stress. All p53 family proteins p53, p63 and p73 act as stress-responsive transcription factors. Oxidation of p53 central DNA binding domain destroys its structure and abolishes its sequence-specific binding by affecting zinc ion coordination at the protein-DNA interface. Proteins p63 and p73 can bind the same response elements as p53 but exhibit distinct functions. Moreover, all three proteins contain highly conserved cysteines in central DNA binding domain suitable for possible redox modulation. In this work we report for the first time the redox sensitivity of p63 and p73 core domains to a thiol oxidizing agent azodicarboxylic acid bis[dimethylamide] (diamide). Oxidation of both p63 and p73 abolished sequence-specific binding to p53 consensus sequence, depending on the agent concentration. In the presence of specific DNA all p53 family core domains were partially protected against loss of DNA binding activity due to diamide treatment. Furthermore, we detected conditional reversibility of core domain oxidation for all p53 family members and a role of zinc ions in this process. We showed that p63 and p73 proteins had greater ability to resist the diamide oxidation in comparison with p53. Our results show p63 and p73 as redox sensitive proteins with possible functionality in response of p53 family proteins to oxidative stress.
authors.affiliation: Institute of Biophysics, Academy of Science of The Czech Republic, v.v.i., Královopolská 135, 612 65 Brno, Czech Republic.
authors.forename: Vlastimil
authors.initials: V
authors.lastname: Tichý
authors.forename: Lucie
authors.initials: L
authors.lastname: Navrátilová
authors.forename: Matej
authors.initials: M
authors.lastname: Adámik
authors.forename: Miroslav
authors.initials: M
authors.lastname: Fojta
authors.forename: Marie
authors.initials: M
authors.lastname: Brázdová
mesh_terms: D001483:Base Sequence; D003545:Cysteine / Q000737:chemistry; D004247:DNA / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D003958:Diamide / Q000737:chemistry; D004229:Dithiothreitol / Q000737:chemistry; D004492:Edetic Acid / Q000737:chemistry; D004587:Electrophoresis, Agar Gel; D024202:Electrophoretic Mobility Shift Assay; D006801:Humans; D009687:Nuclear Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D010084:Oxidation-Reduction; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D000072160:Tumor Protein p73; D016159:Tumor Suppressor Protein p53 / Q000138:chemical synthesis / Q000737:chemistry*; D025521:Tumor Suppressor Proteins / Q000138:chemical synthesis / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry
chemical_list: D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C000606460:TP73 protein, human; D000072160:Tumor Protein p73; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D003958:Diamide; D004247:DNA; D004492:Edetic Acid; D015032:Zinc; D003545:Cysteine; D004229:Dithiothreitol