Structures of p53 cancer mutants and mechanism of rescue by second-site suppressor mutations.
We have solved the crystal structures of three oncogenic mutants of the core domain of the human tumor suppressor p53. The mutations were introduced into a stabilized variant. The cancer hot spot mutation R273H simply removes an arginine involved in DNA binding without causing structural distortions in neighboring residues. In contrast, the "structural" oncogenic mutations H168R and R249S induce substantial structural perturbation around the mutation site in the L2 and L3 loops, respectively. H168R is a specific intragenic suppressor mutation for R249S. When both cancer mutations are combined in the same molecule, Arg(168) mimics the role of Arg(249) in wild type, and the wild type conformation is largely restored in both loops. Our structural and biophysical data provide compelling evidence for the mechanism of rescue of mutant p53 by intragenic suppressor mutations and reveal features by which proteins can adapt to deleterious mutations.
Joerger
Andreas C
AC
Centre for Protein Engineering, Medical Research Council, Cambridge, CB2 2QH, United Kingdom.
Ang
Hwee Ching
HC
Veprintsev
Dmitry B
DB
Blair
Caroline M
CM
Fersht
Alan R
AR
D001120:Arginine / Q000235:genetics / Q000378:metabolism; D018360:Crystallography, X-Ray; D004247:DNA / Q000378:metabolism; D006801:Humans; D009154:Mutation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000235:genetics*
D016159:Tumor Suppressor Protein p53; D004247:DNA; D001120:Arginine