Related Experiment Videos
"Rescued" SV40: increased transforming efficiency in mouse and human cells
Abstract:
Plaque-size mutants of simian virus 40 (SV40) have been characterized with respect to their ability to transform mouse and human cells in vitro. Large plaque mutants of SV40 were extremely inefficient at transforming mouse or human cells, requiring approximately 50 times more infectious particles per transformation event than did the small plaque mutants. The minute plaque SV40 was the most efficient, requiring less than 10(3) plaque-forming units per transformation in mouse Balb/3T3 cells and only 1.5 x 10(4) plaque-forming units per transformation unit in the "susceptible" human strains. Both small and minute plaque virus were unable to help the large plaque virus to transform. Virus "rescued" from transformed 3T3 cells by cocultivation with monkey kidney cells was more efficient at transformation than the parental type. The increased efficiency could be shown for each plaque type and in human as well as in mouse cells. The property of "high efficiency transformation" is stable through at least two passages in monkey kidney cells.
Insights
Minute plaque simian virus 40 (SV40) mutants exhibit the highest cell transformation efficiency. Rescued virus from transformed cells also shows enhanced transformation capabilities, a stable trait.
Area of Science:
- Virology
- Cell Biology
- Oncogenesis
Background:
- Simian virus 40 (SV40) is a versatile DNA tumor virus.
- SV40 plaque morphology correlates with biological activity.
- Understanding SV40 transformation efficiency is crucial for viral oncogenesis research.
Purpose of the Study:
- To characterize plaque-size mutants of SV40 for their in vitro cell transformation efficiency.
- To compare the transformation capabilities of large, small, and minute plaque SV40 mutants.
- To investigate the transformation efficiency of virus rescued from transformed cells.
Main Methods:
- In vitro transformation assays using mouse Balb/3T3 and human cell lines.
- Characterization of SV40 plaque-size mutants.
- Cocultivation of transformed cells with monkey kidney cells to rescue virus.
Main Results:
- Minute plaque SV40 mutants demonstrated the highest transformation efficiency in both mouse and human cells.
- Large plaque mutants were significantly less efficient transformers compared to small plaque mutants.
- Virus rescued from transformed mouse cells exhibited enhanced transformation efficiency, a property stable through passages.
Conclusions:
- SV40 plaque size is a critical determinant of in vitro transformation efficiency.
- Genetic alterations in rescued SV40 contribute to increased transformation potential.
- These findings provide insights into the mechanisms of SV40-mediated cell transformation.