Oligomerization of the human ARF tumor suppressor and its response to oxidative stress.
The tumor suppressor ARF plays an important role as an inhibitor of the Mdm2-mediated degradation of p53. Here we demonstrate that human ARF (p14ARF) can form homo-oligomers. The stability of the oligomers is favored by oxidizing agents in a reversible fashion and involves all three cysteine residues in p14ARF. Furthermore, the effect of p14ARF in clonogenic assays is moderately but reproducibly increased by the mutation of its cysteine residues. We also observed that altering the amino terminus of p14ARF resulted in the appearance of remarkably stable oligomers. This indicates that the amino terminus of p14ARF interferes with the ability of the protein to form multimeric complexes. These observations suggest that p14ARF activity may be linked to its oligomerization status and sensitive to the redox status of the cell.
Menéndez
Sergio
S
Department of Surgery and Molecular Oncology, the University of Dundee, Ninewells Hospital and Medical School, Dundee DD1 9SY, Scotland, United Kingdom.
Khan
Zeb
Z
Coomber
David W
DW
Lane
David P
DP
Higgins
Maureen
M
Koufali
Maria M
MM
Lain
Sonia
S
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D003545:Cysteine / Q000737:chemistry / Q000235:genetics; D019281:Dimerization; D004355:Drug Stability; D017353:Gene Deletion; D015870:Gene Expression; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007163:Immunosorbent Techniques; D046911:Macromolecular Substances; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016297:Mutagenesis, Site-Directed; D009687:Nuclear Proteins; D009893:Opossums; D016877:Oxidants / Q000494:pharmacology; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051736:Proto-Oncogene Proteins c-mdm2; D011994:Recombinant Proteins / Q000737:chemistry; D014162:Transfection; D025803:Tumor Suppressor Protein p14ARF / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
D046911:Macromolecular Substances; D009687:Nuclear Proteins; D016877:Oxidants; D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D025803:Tumor Suppressor Protein p14ARF; D006861:Hydrogen Peroxide; C497206:MDM2 protein, human; C497207:Mdm2 protein, mouse; D051736:Proto-Oncogene Proteins c-mdm2; D003545:Cysteine