Binding of natively unfolded HIF-1alpha ODD domain to p53.
Hypoxia-inducible factor-1 (HIF-1) is a heterodimeric transcription factor that plays a crucial role in mediating oxygen response in the cell. Using biophysical techniques, we characterized two fragments of the HIF-1alpha subunit, one the full-length ODD domain (residues 403-603) and the second comprising the N-TAD (N-transactivation domain) and inhibitory domain (residues 530-698). Both were unstructured in solution under physiological conditions and so belong to the family of natively unfolded proteins. The HIF-1alpha ODD domain binds weakly to the isolated p53 core domain but tightly to full-length p53 to give a complex of one HIF-1alpha ODD domain with a p53 dimer. By being unstructured, the HIF-1alpha ODD domain can thread both its binding sites through the p53 multimer and bind tightly by the "chelate effect." These results support the idea that hypoxic p53-mediated apoptosis does involve the direct binding of HIF-1alpha to p53.
Sánchez-Puig
Nuria
N
Centre for Protein Engineering, Medical Research Council, Hills Road, CB2 2QH, Cambridge, United Kingdom.
Veprintsev
Dmitry B
DB
Fersht
Alan R
AR
D017209:Apoptosis; D001483:Base Sequence; D001665:Binding Sites; D002942:Circular Dichroism; D004247:DNA / Q000235:genetics; D004268:DNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D000860:Hypoxia / Q000378:metabolism / Q000473:pathology; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D066298:In Vitro Techniques; D007700:Kinetics; D046912:Multiprotein Complexes; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009994:Osmolar Concentration; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D004268:DNA-Binding Proteins; C497442:HIF1A protein, human; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D046912:Multiprotein Complexes; D009687:Nuclear Proteins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53; D004247:DNA