Analysis of A-MuLV transformed fibroblast lines for amplification of the c-myc, p53 and c-fos nuclear proto-oncogenes.
Aberrations in nuclear proto-oncogene organisation and/or gene expression have been implicated in cell transformation mediated by the v-abl gene. For example, it has been suggested that amplification of the c-myc proto-oncogene is a co-operative event in v-abl induced fibroblast transformation. We have investigated amplification of the c-myc, p53 and c-fos nuclear proto-oncogenes in several Abelson murine leukaemia virus (A-MuLV) transformed fibroblast lines. None of these proto-oncogenes were detectably rearranged or amplified in v-abl transformed Swiss 3T3 lines. In contrast, NIH3T3 fibroblasts transformed by the v-abl gene consistently showed a 4 to 16-fold amplification of the c-myc gene. These data show that c-myc gene amplification is not an obligatory event associated with A-MuLV transformation, but may be restricted to cell lines derived from NIH3T3. c-myc gene amplification also did not correlate with a reduced latency period for tumour induction in nude mice. In addition, c-myc amplification was not selected during tumourigenesis, indicating that this event is not required for A-MuLV transformed Swiss 3T3 cells to display a full tumourigenic phenotype.
Colledge
W H
WH
Laboratory of Eukaryotic Molecular Genetics, National Institute for Medical Research, Mill Hill, London.
Gebhardt
A
A
Edge
M D
MD
Bell
J C
JC
D000011:Abelson murine leukemia virus / Q000235:genetics*; D000818:Animals; D015139:Blotting, Southern; D002461:Cell Line, Transformed; D005347:Fibroblasts / Q000382:microbiology* / Q000648:ultrastructure; D005784:Gene Amplification; D009052:Leukemia Virus, Murine / Q000235:genetics*; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000096:biosynthesis
D012333:RNA, Messenger