Solution structure of the Ras-binding domain of c-Raf-1 and identification of its Ras interaction surface.
The structure of the Ras-binding domain of human c-Raf-1 (residues 55-132) has been determined in solution by nuclear magnetic resonance (NMR) spectroscopy. Following complete assignment of the backbone and side-chain 1H, 15N, and 13C resonances, the structure was calculated using the program CHARMM. Over 1300 NOE-derived constraints were applied, resulting in a detailed structure. The fold of Raf55-132 consists of a five-stranded beta-sheet, a 12-residue alpha-helix, and an additional one-turn helix. It is similar to those of ubiquitin and the IgG-binding domain of protein G, although the three proteins share very little sequence identity. The surface of Raf55-132 that interacts with Ras has been identified by monitoring perturbation of line widths and chemical shifts of 15N-labeled Raf55-132 resonances during titration with unlabeled Ras-GMPPNP. The Ras-binding site is contained within a spatially contiguous patch comprised of the N-terminal beta-hairpin and the C-terminal end of the alpha-helix.
Emerson
S D
SD
Roche Research Center, Hoffmann-La Roche Inc., Nutley, New Jersey 07110, USA.
Madison
V S
VS
Palermo
R E
RE
Waugh
D S
DS
Scheffler
J E
JE
Tsao
K L
KL
Kiefer
S E
SE
Liu
S P
SP
Fry
D C
DC
D001665:Binding Sites; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D011487:Protein Conformation; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000378:metabolism*; D019908:Proto-Oncogene Proteins c-raf; D012996:Solutions; D018631:ras Proteins / Q000378:metabolism*
D011518:Proto-Oncogene Proteins; D012996:Solutions; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D018631:ras Proteins