Abstract
Infection of normal rat fibroblasts (FR 3T3) with the early tsa mutant of polyoma virus may lead to either the A or the N phenotype, tsa-A transformants, originally derived by agar selection, are not temperature dependent for maintenance of the transformed phenotype, whereas tsa-N transormants revert at high temperature to normal growth control. A transformants did not result from an independent cellular mutation selected in agar medium, but rather from a transformation process distinct from that leading to the N state. It occurred in both liquid and agar media when the infected cells were maintained under growth-restricting conditions, such as absence of anchorage and contact inhibition at confluency. N transformation occurred in cells maintained in active growth after virus infection (sparse cultures on a solid substratum). Physiological conditions during a critical period after virus infection thus appear to be a crucial parameter of the transformation process.
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Brockman W. W. Transformation of BALB/c-3T3 cells by tsA mutants of simian virus 40: temperature sensitivity of the transformed phenotype and retransofrmation by wild-type virus. J Virol. 1978 Mar;25(3):860–870. doi: 10.1128/jvi.25.3.860-870.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Di Mayorca G., Callender J., Marin G., Giordano R. Temperature-sensitive mutants of polyoma virus. Virology. 1969 May;38(1):126–133. doi: 10.1016/0042-6822(69)90134-2. [DOI] [PubMed] [Google Scholar]
- Eckhart W. Complementation and transformation by temperature-sensitive mutants of polyoma virus. Virology. 1969 May;38(1):120–125. doi: 10.1016/0042-6822(69)90133-0. [DOI] [PubMed] [Google Scholar]
- FRIED M. CELL-TRANSFORMING ABILITY OF A TEMPERATURE-SENSITIVE MUTANT OF POLYOMA VIRUS. Proc Natl Acad Sci U S A. 1965 Mar;53:486–491. doi: 10.1073/pnas.53.3.486. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fried M. Characterization of a temperature-sensitive mutant of polyoma virus. Virology. 1970 Mar;40(3):605–617. doi: 10.1016/0042-6822(70)90205-9. [DOI] [PubMed] [Google Scholar]
- Kimura G., Itagaki A. Initiation and maintenance of cell transformation by simian virus 40: a viral genetic property. Proc Natl Acad Sci U S A. 1975 Feb;72(2):673–677. doi: 10.1073/pnas.72.2.673. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MACPHERSON I., MONTAGNIER L. AGAR SUSPENSION CULTURE FOR THE SELECTIVE ASSAY OF CELLS TRANSFORMED BY POLYOMA VIRUS. Virology. 1964 Jun;23:291–294. doi: 10.1016/0042-6822(64)90301-0. [DOI] [PubMed] [Google Scholar]
- Rassoulzadegan M., Perbal B., Cuzin F. Growth control in simian virus 40-transformed rat cells: temperature-independent expression of the transformed phenotype in tsA transformants derived by agar selection. J Virol. 1978 Oct;28(1):1–5. doi: 10.1128/jvi.28.1.1-5.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Risser R., Pollack R. A nonselective analysis of SV40 transformation of mouse 3T3 cells. Virology. 1974 Jun;59(2):477–489. doi: 10.1016/0042-6822(74)90457-7. [DOI] [PubMed] [Google Scholar]
- Seif R., Cuzin F. Temperature-sensitive growth regulation in one type of transformed rat cells induced by the tsa mutant of polyoma virus. J Virol. 1977 Dec;24(3):721–728. doi: 10.1128/jvi.24.3.721-728.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tegtmeyer P. Function of simian virus 40 gene A in transforming infection. J Virol. 1975 Mar;15(3):613–618. doi: 10.1128/jvi.15.3.613-618.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
- VOGT M., DULBECCO R. Steps in the neoplastic transformation of hamster embryo cells by polyoma virus. Proc Natl Acad Sci U S A. 1963 Feb 15;49:171–179. doi: 10.1073/pnas.49.2.171. [DOI] [PMC free article] [PubMed] [Google Scholar]