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Published on: November 1, 2011
Baculovirus lef-12 is not required for viral replication.
Linda A Guarino1, Toni-Ann Mistretta, Wen Dong
1Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, USA. lguarino@tamu.edu
Journal of Virology
|November 5, 2002
Summary
The baculovirus LEF-12 protein is crucial for efficient viral replication. Its absence significantly reduces virus yields, though late gene expression remains largely unaffected.
Area of Science:
- Molecular Biology
- Virology
- Genetics
Background:
- The baculovirus lef-12 (orf41) gene plays a role in the transient expression of viral late genes.
- Understanding the function of LEF-12 in infected cells is essential for comprehending baculovirus replication cycles.
Purpose of the Study:
- To investigate the precise role of the LEF-12 protein in baculovirus-infected cells.
- To construct and analyze mutant viruses lacking functional LEF-12.
Main Methods:
- Construction of two mutant baculoviruses lacking the lef-12 gene.
- Single-step growth curve analysis to determine viral yields.
- Pulse-labeling and Western blot analysis to assess protein synthesis.
- Primer extension mapping to analyze lef-12 mRNA expression.
- Inhibition studies using aphidicolin to determine the timing of lef-12 expression relative to DNA replication.
Main Results:
- Mutant viruses lacking LEF-12 were viable but exhibited a fivefold reduction in virus yield.
- Late gene expression and entry into the late phase of infection were not significantly impaired in LEF-12 mutants.
- LEF-12 protein and mRNA synthesis were detected after 12-18 hours post-infection and were inhibited by aphidicolin, indicating post-DNA replication expression.
Conclusions:
- LEF-12 is essential for optimal baculovirus replication, significantly impacting viral yield.
- While LEF-12 is not strictly required for late gene expression, its absence affects overall virus production.
- The expression of lef-12 is temporally regulated and occurs after viral DNA replication.
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