Related Experiment Videos
Immortalizing genes of Epstein-Barr virus
T Middleton1, T A Gahn, J M Martin
1McArdle Laboratory for Cancer Research, University of Wisconsin, Madison 53706.
Advances in Virus Research
|January 1, 1991
Summary
Epstein-Barr virus (EBV) immortalizes human B lymphocytes using several viral genes. Key genes like EBNA-2, LMP, and EBNA-1 play crucial roles in this complex cellular transformation process.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Epstein-Barr virus (EBV) is known to efficiently immortalize human B lymphocytes.
- Approximately 10 EBV genes are expressed in lymphoblasts, with several being candidates for mediating immortalization.
- Understanding the roles of these viral genes is crucial for comprehending B lymphocyte immortalization.
Purpose of the Study:
- To investigate the roles of specific Epstein-Barr virus (EBV) genes in the immortalization of human B lymphocytes.
- To explore the biochemical activities and mechanisms of action of EBV proteins involved in cellular transformation.
- To clarify the contribution of viral genes to the phenotypic changes observed in EBV-infected B lymphocytes.
Main Methods:
- Genetic studies to determine the requirement of EBNA-2 for EBV-mediated immortalization.
- Analysis of RNA accumulation in EBV-negative B-lymphoblastoid cells to understand EBNA-2 effects.
- Biochemical and structural analysis of LMP, including studies of mutant derivatives.
- Investigation of EBNA-1's role in viral DNA replication and transcription regulation, including its binding to oriP and cellular proteins.
Main Results:
- EBNA-2 is genetically confirmed to be essential for EBV to immortalize B lymphocytes, affecting viral and cellular RNA accumulation.
- LMP's properties suggest a role in growth factor signaling, potentially transforming cells, but its direct biochemical activity remains unassigned.
- EBNA-1 is essential for EBV plasmid DNA replication initiation and likely sustains viral DNA replication and regulates viral gene transcription.
Conclusions:
- EBV utilizes multiple viral genes, including EBNA-2, LMP, and EBNA-1, to alter B lymphocyte physiology and achieve immortalization.
- While EBNA-2 and EBNA-1 have defined roles in replication and transcription, LMP's mechanism of action in immortalization remains enigmatic.
- Further research is needed to fully elucidate the biochemical activities and precise contributions of these EBV genes to host cell immortalization.