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Production of Replication-Defective Retrovirus by Transient Transfection of 293T cells
Published on: December 4, 2007
Two independent mutations are required for temperature-sensitive cell transformation by a Rous sarcoma virus
Journal of Virology
|December 1, 1985
Summary
Researchers identified specific mutations in the Rous sarcoma virus src gene responsible for its temperature-sensitive transformation. These findings pinpoint key genetic alterations affecting viral oncogenic activity.
Area of Science:
- * Molecular biology
- * Virology
- * Oncology
Background:
- * Rous sarcoma virus (RSV) is a retrovirus known for its oncogenic properties.
- * Temperature-sensitive (ts) mutants of RSV, like tsNY68, allow for the study of viral gene function at different temperatures.
- * The src gene is a key viral oncogene in RSV, crucial for cell transformation.
Purpose of the Study:
- * To molecularly clone and characterize the src coding region of the tsNY68 mutant RSV.
- * To identify the specific mutations within the src gene responsible for the temperature-sensitive transformation phenotype.
- * To construct and analyze recombinant src genes to confirm the role of identified mutations.
Main Methods:
- * Molecular cloning of the src coding region from tsNY68.
- * Construction of ts wild-type recombinant src genes.
- * Transfection of chicken cells with hybrid genes, viral vector DNA, and helper viral DNA.
- * Recovery and characterization of infectious transforming viruses.
- * Nucleotide sequence analysis of the src gene.
Main Results:
- * Infectious transforming viruses were recovered from transfected chicken cells.
- * Characterization revealed at least two mutations in the 3' half of the mutant src gene are essential for the temperature-sensitive phenotype.
- * Nucleotide sequence analysis identified three amino acid differences compared to the parental virus.
- * A deletion of amino acids 352–354 and an amino acid substitution at position 461 were identified as responsible for the ts phenotype.
Conclusions:
- * The temperature-sensitive transformation of tsNY68 is attributed to specific mutations within its src gene.
- * The identified deletion and substitution mutations are critical for the temperature-sensitive nature of the src gene.
- * These findings provide a detailed molecular understanding of src gene function and its role in viral transformation.
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