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Updated: Aug 9, 2026

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Production of Replication-Defective Retrovirus by Transient Transfection of 293T cells
Published on: December 4, 2007
Sequences present in both human leukemic cell nuclear DNA and Rauscher leukemia virus
Summary
Researchers identified specific DNA sequences in human leukemia cells that match Rauscher leukemia virus. This viral DNA is found in infected mouse spleen and human leukemia cells, but not in healthy cells.
Area of Science:
- Molecular Biology
- Virology
- Oncology
Background:
- Particulate fractions from human leukemic white blood cells synthesize DNA.
- Rauscher leukemia virus (RLV) is an oncogenic retrovirus.
- Identifying viral genetic material in host cells is crucial for understanding viral pathogenesis.
Purpose of the Study:
- To subfractionate DNA synthesized by human leukemic white blood cells.
- To determine if this synthesized DNA contains sequences specific to Rauscher leukemia virus.
- To compare the presence of these sequences in normal versus infected cells.
Main Methods:
- Hybridization of synthesized DNA to Rauscher leukemia virus 70S RNA.
- Subfractionation using hydroxylapatite chromatography.
- Hybridization analysis of nuclear DNA from infected and normal Balb/c mouse spleens and human white blood cells.
Main Results:
- A specific DNA fraction complementary to Rauscher leukemia virus RNA was isolated.
- This viral DNA fraction was found in nuclear DNA of RLV-infected mouse spleens.
- The viral DNA fraction was also present in nuclear DNA from human leukemic white blood cells.
Conclusions:
- Human leukemic white blood cells contain DNA sequences specific to Rauscher leukemia virus.
- These viral sequences are absent in normal human white blood cells and normal mouse spleen cells.
- The findings suggest a potential role of RLV-related sequences in human leukemia.
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