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Assembly and Purification of Prototype Foamy Virus Intasomes
Published on: March 19, 2018
Functional and structural characterization of the integrase from the prototype foamy virus
Eugene Valkov1, Saumya Shree Gupta, Stephen Hare
1Division of Medicine, St. Mary's Campus, Imperial College London, London, UK.
Nucleic Acids Research
|November 28, 2008
Summary
We characterized prototype foamy virus integrase (IN) and determined its structure. PFV IN shows robust integration activity and sensitivity to HIV IN inhibitors, revealing conserved targets for antiviral drug development.
Area of Science:
- Retroviral replication mechanisms
- Structural biology of viral enzymes
- Antiviral drug discovery
Background:
- Integrase (IN) is crucial for stable provirus establishment during retroviral replication.
- Structural data for retroviral INs were previously limited to specific genera like Lentivirus and Alpharetrovirus.
Purpose of the Study:
- To characterize the in vitro activity of prototype foamy virus (PFV) integrase (IN).
- To determine the three-dimensional structure of the PFV IN catalytic core domain (CCD).
- To compare structural features of PFV IN with other characterized retroviral INs.
Main Methods:
- Recombinant protein expression and purification of PFV IN.
- In vitro integration assays using varying donor DNA lengths.
- X-ray crystallography to determine the 3D structure of the PFV IN catalytic core domain.
Main Results:
- PFV IN demonstrated robust and specific concerted integration activity in vitro.
- The 3D structure of the PFV IN catalytic core domain was determined.
- Structural comparisons revealed conserved and unique features in the active site and host factor binding face across different retroviral INs.
- PFV IN exhibited sensitivity to HIV IN strand transfer inhibitors despite low sequence homology.
Conclusions:
- PFV IN serves as a valuable model for structural studies of retroviral integrases.
- Structural insights highlight conserved elements within retroviral INs crucial for DNA integration.
- The sensitivity of PFV IN to HIV IN inhibitors suggests a conserved mechanism targeted by this drug class.
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