p21H-ras-induced morphological transformation and increases in c-myc expression are independent of functional protein kinase C.
It has previously been demonstrated that efficient DNA synthesis by oncogenic p21H-ras only occurs in the presence of insulin and is absolutely dependent on functional protein kinase C. Here we show that morphological transformation induced by oncogenic p21H-ras does not require functional protein kinase C. The early phases of protein kinase C-independent morphological transformation do not require de novo protein synthesis. We have also demonstrated that the introduction of p21H-ras into quiescent Swiss 3T3 cells by scrape-loading leads to increased levels of c-myc mRNA similar to those seen following serum stimulation. The increases in c-myc mRNA levels induced by p21H-ras are also independent of functional protein kinase C. Both morphological transformation and the elevation of c-myc mRNA levels do not require insulin. These results demonstrate that p21H-ras is generating protein kinase C-dependent and -independent signals.
Lloyd
A C
AC
Institute of Cancer Research, Chester Beatty Laboratories, London, UK.
Paterson
H F
HF
Morris
J D
JD
Hall
A
A
Marshall
C J
CJ
D000818:Animals; D002471:Cell Transformation, Neoplastic; D004247:DNA / Q000096:biosynthesis; D005786:Gene Expression Regulation; D014176:Protein Biosynthesis; D011493:Protein Kinase C / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D016271:Proto-Oncogene Proteins c-myc; D016283:Proto-Oncogene Proteins p21(ras); D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
D011518:Proto-Oncogene Proteins; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger; D004247:DNA; D011493:Protein Kinase C; D016283:Proto-Oncogene Proteins p21(ras)