Mutagenic analysis of the v-crk oncogene: requirement for SH2 and SH3 domains and correlation between increased cellular phosphotyrosine and transformation.
We have constructed a series of mutants with deletion, linker insertion, and point mutations in the v-crk oncogene of avian sarcoma virus CT10. The v-crk gene contains no apparent catalytic domain, but does contain two blocks of homology to putative regulatory domains, termed SH2 and SH3, found in a variety of proteins implicated in signal transduction. Infection with CT10 causes a dramatic increase in the level of tyrosine phosphorylation of several cellular proteins. We found that mutation of either the SH2 or SH3 domain of v-crk reduced or eliminated transforming activity, whereas mutation of regions outside the conserved domains had no effect. Deletion of amino-terminal gag sequences caused a partial loss of transforming activity and a change in subcellular distribution of the crk protein. In all cases, there was an absolute correlation between increased cellular phosphotyrosine and transformation.
Laboratory of Molecular Oncology, Rockefeller University, New York, New York 10021.
B J
BJ
Mayer
H
H
Hanafusa
D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics*; D001483:Base Sequence; D002448:Cell Adhesion; D002455:Cell Division; D002471:Cell Transformation, Neoplastic; D002642:Chick Embryo; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D050736:Oncogene Protein v-crk; D009857:Oncogenes; D010750:Phosphoproteins / Q000302:isolation & purification; D019000:Phosphotyrosine; D010957:Plasmids; D015183:Restriction Mapping; D015682:Retroviridae Proteins, Oncogenic / Q000235:genetics*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
D015345:Oligonucleotide Probes; D050736:Oncogene Protein v-crk; D010750:Phosphoproteins; D015682:Retroviridae Proteins, Oncogenic; D019000:Phosphotyrosine; D014443:Tyrosine