Induction of transformation and DNA synthesis after microinjection of raf proteins.
Full-length and N-terminal deletion mutants of human c-raf-1 cDNA were cloned into Escherichia coli expression plasmids. Bacterially expressed c-raf proteins were purified by anion-exchange, gel filtration, and affinity chromatography. Microinjection of mutant c-raf proteins into G0-arrested NIH 3T3 cells induced DNA synthesis and morphological transformation, whereas microinjection of full-length c-raf had no effect. The amino terminus of the raf protein has an important negative regulatory influence; alteration of this region resulted in increased kinase activity and oncogenicity.
Biological Carcinogenesis and Development Program, Program Resources, Inc., National Cancer Institute-Frederick Cancer Research Facility, Maryland 21701.
M R
MR
Smith
G
G
Heidecker
U R
UR
Rapp
H F
HF
Kung
D000818:Animals; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004261:DNA Replication; D004926:Escherichia coli / Q000235:genetics; D006801:Humans; D051379:Mice; D008845:Microinjections; D009154:Mutation; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism*; D019908:Proto-Oncogene Proteins c-raf; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000378:metabolism; D015183:Restriction Mapping
D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D011505:Protein-Tyrosine Kinases; D019908:Proto-Oncogene Proteins c-raf