title: P14ARF promotes accumulation of SUMO-1 conjugated (H)Mdm2.
abstract: p14ARF tumour suppressor stabilises and activates p53 by directly interacting with (H)Mdm2 [(human) murine double minute 2 homologue] and inhibiting its E3 ubiquitin ligase activity. Here we demonstrate that p14ARF promotes accumulation of (H)Mdm2 conjugated to the small ubiquitin-like protein SUMO-1. Mutational analysis demonstrated that the N-terminus of Mdm2 is a target for p14ARF-mediated SUMO conjugation. SUMO modification requires residues 2-14 in p14ARF that interact with (H)Mdm2 and residues 82-101 in exon 2 involved in nucleolar localisation of p14ARF. These data suggest a novel role for p14ARF as a regulator of activity of (H)Mdm2, which could be related to its tumour suppressing activities.
authors.affiliation: University of Dundee, Ninewells Hospital and Medical School, Department of Surgery and Molecular Oncology, UK.
authors.forename: Dimitris P
authors.initials: DP
authors.lastname: Xirodimas
authors.forename: June
authors.initials: J
authors.lastname: Chisholm
authors.forename: Joana M S
authors.initials: JM
authors.lastname: Desterro
authors.forename: David P
authors.initials: DP
authors.lastname: Lane
authors.forename: Ronald T
authors.initials: RT
authors.lastname: Hay
mesh_terms: D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D005091:Exons; D006801:Humans; D046911:Macromolecular Substances; D051379:Mice; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051736:Proto-Oncogene Proteins c-mdm2; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D025842:SUMO-1 Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017384:Sequence Deletion; D014162:Transfection; D025803:Tumor Suppressor Protein p14ARF / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D046911:Macromolecular Substances; D009687:Nuclear Proteins; D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D025842:SUMO-1 Protein; D025803:Tumor Suppressor Protein p14ARF; D016159:Tumor Suppressor Protein p53; C497206:MDM2 protein, human; C497207:Mdm2 protein, mouse; D051736:Proto-Oncogene Proteins c-mdm2