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A Protocol for the Production of Integrase-deficient Lentiviral Vectors for CRISPR/Cas9-mediated Gene Knockout in Dividing Cells
Published on: December 12, 2017
The SSV1 viral integrase is not essential
Adam J Clore1, Kenneth M Stedman
1Biology Department, Center for Life in Extreme Environments, Portland State University, P.O. Box 751, Portland, OR 97207, USA. adam.clore@gmail.com
Virology
|December 19, 2006
Summary
Viral integration is not essential for SSV1 virus replication in Sulfolobus solfataricus. Removing the integrase allowed viral spread, though the mutant virus showed reduced competitiveness, highlighting potential advantages of integration.
Area of Science:
- Virology
- Archaea Biology
- Molecular Biology
Background:
- Viral integration is a conserved process across life, but its necessity is often unclear.
- Tyrosine recombinases mediate widespread and well-understood viral integration mechanisms.
- The hyperthermophilic archaeal virus SSV1 infects Sulfolobus solfataricus.
Purpose of the Study:
- To investigate the necessity of viral integration for SSV1 replication.
- To determine the role of tyrosine recombinase integrase in the SSV1 life cycle.
- To assess the impact of integrase absence on viral infectivity and competitiveness.
Main Methods:
- Utilized a novel Lysis-Induced Polymerase Chain Reaction (LIPCR) technique.
- Completely removed the tyrosine recombinase integrase gene from the SSV1 genome.
- Co-cultured wild-type and integrase-deficient SSV1 mutants with Sulfolobus solfataricus.
Main Results:
- The integrase-deficient SSV1 mutant successfully replicated and spread within Sulfolobus solfataricus.
- The mutant virus established a persistent infection despite the absence of integration.
- Integrase-lacking SSV1 demonstrated reduced competitiveness compared to the wild-type virus during co-cultivation.
Conclusions:
- Viral integration, mediated by integrase, is not strictly essential for SSV1 replication and spread.
- The absence of integration may confer disadvantages in viral competitiveness.
- This study provides insights into the evolutionary advantages and necessity of viral integration strategies.
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