TY - JOUR

T1 - Harvey murine sarcoma virus p21 ras protein: biological and biochemical significance of the cysteine nearest the carboxy terminus.

AU - Willumsen, B M

AU - Norris, K

AU - Papageorge, A G

AU - Hubbert, N L

AU - Lowy, D R

N1 - Keywords: Animals; Base Sequence; Cell Transformation, Neoplastic; Cells, Cultured; Cysteine; Genes, Viral; Harvey murine sarcoma virus; Mice; Mice, Inbred Strains; Mutation; Neoplasm Proteins; Nucleic Acid Hybridization; Oncogenes; Plasmids; Proto-Oncogene Proteins p21(ras); Sarcoma Viruses, Murine; Species Specificity; Transfection

PY - 1984

Y1 - 1984

N2 - Previous studies of premature chain termination mutants and in frame deletion mutants of the p21 ras transforming protein encoded by the transforming gene of Harvey murine sarcoma virus (Ha-MuSV) have suggested that the C terminus is required for cellular transformation, lipid binding, and membrane localization. We have now further characterized the post-translational processing of these mutants and have also studied two C-terminal v-rasH point mutants: one encodes serine in place of cysteine-186, the other threonine for valine-187. The Thr-187 mutant was transformation-competent, and its p21 protein was processed normally, as was the p21 encoded by a transformation-competent deletion mutant from which amino acids 166-175 had been deleted. The Ser-186 mutant was defective for transformation. The p21s encoded by the Ser-186 mutant and by the previously described transformation-defective mutants did not undergo the posttranslational processing common to biologically active ras proteins: their electrophoretic migration rate did not change, they remained in the cytosol, and they failed to bind lipid. Since the cell-encoded ras proteins also contain this cysteine, we conclude that this amino acid residue is required for all ras proteins.

AB - Previous studies of premature chain termination mutants and in frame deletion mutants of the p21 ras transforming protein encoded by the transforming gene of Harvey murine sarcoma virus (Ha-MuSV) have suggested that the C terminus is required for cellular transformation, lipid binding, and membrane localization. We have now further characterized the post-translational processing of these mutants and have also studied two C-terminal v-rasH point mutants: one encodes serine in place of cysteine-186, the other threonine for valine-187. The Thr-187 mutant was transformation-competent, and its p21 protein was processed normally, as was the p21 encoded by a transformation-competent deletion mutant from which amino acids 166-175 had been deleted. The Ser-186 mutant was defective for transformation. The p21s encoded by the Ser-186 mutant and by the previously described transformation-defective mutants did not undergo the posttranslational processing common to biologically active ras proteins: their electrophoretic migration rate did not change, they remained in the cytosol, and they failed to bind lipid. Since the cell-encoded ras proteins also contain this cysteine, we conclude that this amino acid residue is required for all ras proteins.

M3 - Journal article

C2 - 6096132

VL - 3

SP - 2581

EP - 2585

JO - E M B O Journal

JF - E M B O Journal

SN - 0261-4189

IS - 11

ER -