Loss of Raf-1-binding activity of v-Ha-Ras by the deletion of amino acid residues 64-72 and 143-151.
In order to elucidate the molecular events in signal transduction, examination of the interaction between Ras and Raf-1 seems crucial. Many Raf-1 mutants have been investigated in terms of their binding activities to Ras, where only a few Ras mutants have been examined thus far. We have investigated the Raf-1-binding activities of v-Ha-Ras and 21 insertion/deletion mutants of this protein. The results show that the mutants have varying levels of Raf-1-binding activity that are related neither to their transforming activity nor to their guanine nucleotide-binding activity. Deletion in the effector domain of Ras did not completely abolish Raf-1-binding, whereas the deletion in amino acid residues 64-72 or 143-151 resulted in complete loss of Raf-1-binding activity.
Division of Biochemistry, Chiba Cancer Center Research Institute, Japan.
T
T
Hiwasa
M
M
Kasama
T
T
Nakadai
T
T
Sawada
S
S
Sakiyama
D016296:Mutagenesis; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism*; D019908:Proto-Oncogene Proteins c-raf; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism*
D011518:Proto-Oncogene Proteins; D017346:Protein Serine-Threonine Kinases; D019908:Proto-Oncogene Proteins c-raf; D018631:ras Proteins