AuthorsSchonhoff, Christopher M.
Jones, Stephen N.
Schiffer, Celia A.
Ross, Alonzo H.
UMass Chan AffiliationsDepartment of Cell Biology
Department of Biochemistry and Molecular Pharmacology
Graduate School of Biomedical Sciences
Document TypeJournal Article
KeywordsAmino Acid Sequence; Binding Sites; Cysteine; Dithiothreitol; Enzyme-Linked Immunosorbent Assay; Glutathione; Glutathione Transferase; Humans; Molecular Sequence Data; Mutagenesis, Site-Directed; Mutation; Neoplasm Proteins; *Nuclear Proteins; Protein Binding; Protein Conformation; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-mdm2; Recombinant Fusion Proteins; Sequence Homology, Amino Acid; Triazenes; Tumor Suppressor Protein p53
Medicine and Health Sciences
MetadataShow full item record
AbstractIt has become increasingly evident that nitric oxide exerts its effects, in part, by S-nitrosylation of cysteine residues. We tested in vitro whether nitric oxide may indirectly control p53 by S-nitrosylation and inactivation of the p53 negative regulator, Hdm2. Treatment of Hdm2 with a nitric oxide donor inhibits Hdm2-p53 binding, a critical step in Hdm2 regulation of p53. The presence of excess amounts of cysteine or dithiothreitol blocks this inhibition of binding. Moreover, nitric oxide inhibition of Hdm2-p53 binding was found to be reversible. Sulfhydryl sensitivity and reversibility are consistent with nitrosylation. Finally, we have identified a critical cysteine residue that nitric oxide modifies to disrupt Hdm2-p53 binding. This cysteine is proximal to the Hdm2-p53 binding interface and is conserved across species from zebrafish to humans. Mutation of this residue from a cysteine to an alanine does not interfere with binding but rather eliminates the sensitivity of Hdm2 to nitric oxide inactivation.
Biochemistry. 2002 Nov 19;41(46):13570-4.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/32515
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