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Adenovirus E1B 19K protein is required for efficient DNA replication in U937 cells
1Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan, Republic of China.
Virology
|January 20, 1997
Summary
The adenovirus E1B 19K gene is crucial for viral DNA replication in human monocyte cell lines. Mutant viruses lacking this gene show defective replication and late gene expression in U937 cells.
Area of Science:
- Virology
- Molecular Biology
- Cell Biology
Background:
- Adenovirus E1B 19K protein is known for cell transformation and apoptosis inhibition.
- E1B 19K is typically not essential for viral DNA replication in established human cell lines like HeLa and KB.
Purpose of the Study:
- To investigate the role of the adenovirus E1B 19K gene in viral replication within monocyte cell lines.
- To characterize the replication defects of E1B 19K mutant viruses in U937 cells.
Main Methods:
- Infection of U937 and THP-1 monocyte cell lines with wild-type and E1B 19K mutant adenovirus.
- Analysis of viral DNA synthesis, late gene expression, and RNA splicing patterns.
- Complementation studies using E1A-defective adenovirus (dl312).
Main Results:
- E1B 19K mutant viruses exhibited inefficient replication in U937 cells.
- Defects in viral DNA synthesis and late gene expression were observed in U937 cells infected with E1B 19K mutants.
- Early viral RNA splicing patterns differed between wild-type and mutant infections, and replication defects were complemented by E1A expression.
Conclusions:
- The adenovirus E1B 19K gene is required for efficient viral DNA replication in U937 and THP-1 monocyte cell lines.
- E1B 19K plays a critical role in the onset of the late phase of adenovirus replication in these cells.
- This finding highlights cell-type specific requirements for viral gene function during infection.
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