title: Early gene expression and cellular DNA synthesis after stimulation of quiescent NIH3T3 cells with serum or purified simian virus 40.
abstract: Like growth factors or hormones, the DNA tumor virus simian virus 40 can stimulate quiescent cells to re-enter the S-phase. Time course experiments revealed similar kinetics for the stimulation of cellular DNA synthesis by growth factors or SV40 infection, although there was a delay in DNA synthesis of about 2 h in the case of the SV40 infection. The analysis of the transcriptional activation of proto-oncogenes in cells stimulated by serum or SV40 infection revealed an enhanced transcription of a common set of proto-oncogenes, including c-myc and c-fos. Early on after infection of quiescent cells SV40 induced in addition the transcription of the c-sis gene which did not occur with UV-irradiated SV40 virus. Furthermore, we could demonstrate the presence of growth stimulating activities in medium from SV40 infected quiescent cells, which triggered quiescent cells to re-enter the cell cycle. These data suggest that SV40 might stimulate quiescent cells by inducing the transcription and ultimately the release of growth-factors.
authors.affiliation: Department of Biochemistry, University of Ulm, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Mörike
authors.forename: A
authors.initials: A
authors.lastname: Quaiser
authors.forename: D
authors.initials: D
authors.lastname: Müller
authors.forename: M
authors.initials: M
authors.lastname: Montenarh
mesh_terms: D001790:Blood Physiological Phenomena; D002478:Cells, Cultured; D003470:Culture Media; D004247:DNA / Q000096:biosynthesis*; D006133:Growth Substances / Q000502:physiology; D011519:Proto-Oncogenes; D013539:Simian virus 40 / Q000502:physiology*; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: D003470:Culture Media; D006133:Growth Substances; D004247:DNA