A peptide that binds and stabilizes p53 core domain: Chaperone strategy for rescue of oncogenic mutants

Autor: Mark R. Proctor, Thomas M Rippin, Lars O. Hansson, Penka V. Nikolova, Assaf Friedler, Alan R. Fersht, Dmitry B. Veprintsev, Stefan M.V. Freund, Stefan G.D. Rüdiger
Rok vydání: 2002
Předmět:
Zdroj: Proceedings of the National Academy of Sciences. 99:937-942
ISSN: 1091-6490
0027-8424
DOI: 10.1073/pnas.241629998
Popis: Conformationally compromised oncogenic mutants of the tumor suppressor protein p53 can, in principle, be rescued by small molecules that bind the native, but not the denatured state. We describe a strategy for the rational search for such molecules. A nine-residue peptide, CDB3, which was derived from a p53 binding protein, binds to p53 core domain and stabilizes it in vitro . NMR studies showed that CDB3 bound to p53 at the edge of the DNA binding site, partly overlapping it. The fluorescein-labeled peptide, FL-CDB3, binds wild-type p53 core domain with a dissociation constant of 0.5 μM, and raises the apparent melting temperatures of wild-type and a representative oncogenic mutant, R249S core domain. gadd45 DNA competes with CDB3 and displaces it from its binding site. But this competition does not preclude CDB3 from being a lead compound. CDB3 may act as a “chaperone” that maintains existing or newly synthesized destabilized p53 mutants in a native conformation and then allows transfer to specific DNA, which binds more tightly. Indeed, CDB3 restored specific DNA binding activity to a highly destabilized mutant I195T to close to that of wild-type level.
Databáze: OpenAIRE