title: NBP is the p53 homolog p63.
abstract: We previously identified a non-p53, p53-responsive DNA element (p53RE)-binding protein named NBP, functionally analogous to p53, from human cervical carcinoma Hela cells. Here we report a biochemical study demonstrating that this activity is the recently cloned p53 analog p63. NBP was purified through conventional and DNA affinity chromatography to apparent homogeneity with a prominent polypeptide migrating in between the 43 and 68 kDa positions on a SDS gel. This polypeptide immunoreacted with monoclonal anti-p63 but not anti-p53 or anti-p73 antibodies. Also, NBP co-purified with p63 through each step of fractionation, as detected with anti-p63 antibodies. DNA-protein complexes formed with purified NBP and p53RE-containing oligomers derived from the p21(waf1) promoter were supershifted by anti-p63 but not anti-p53 antibodies. Thus, these results demonstrate that NBP is encoded by the p53 homolog p63 gene.
authors.affiliation: Department of Biochemistry and Molecular Biology, Oregon Health Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97201, USA.
authors.forename: X
authors.initials: X
authors.lastname: Zeng
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: H
authors.initials: H
authors.lastname: Lu
mesh_terms: D015153:Blotting, Western; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D016147:Genes, Tumor Suppressor; D006367:HeLa Cells / Q000737:chemistry; D006801:Humans; D015151:Immunoblotting; D008565:Membrane Proteins; D009687:Nuclear Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010051:Ovarian Neoplasms / Q000473:pathology; D010750:Phosphoproteins / Q000737:chemistry / Q000378:metabolism*; D015534:Trans-Activators; D014157:Transcription Factors; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000378:metabolism*; D025521:Tumor Suppressor Proteins; D002583:Uterine Cervical Neoplasms / Q000473:pathology
chemical_list: C081876:CKAP4 protein, human; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; C083666:Son protein, mouse; C115051:TP63 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; C486419:Trp63 protein, mouse; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins