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Published on: July 15, 2019
Cyclophilin A interacts with diverse lentiviral capsids
1Pathobiology Graduate Program, University of Washington, Seattle, WA 98195, USA. linty@u.washington.edu
Retrovirology
|October 14, 2006
Summary
Lentiviruses, including FIV and SIVagmTAN, bind to cyclophilin A (CypA). This interaction, previously thought limited to HIV-1, is widespread and crucial for lentiviral infection.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Human Immunodeficiency Virus type 1 (HIV-1) capsid (CA) protein binds cyclophilin A (CypA) with high affinity.
- This interaction is vital for early viral lifecycle stages, as blocking it reduces infectivity.
- Previously, CypA binding was believed specific to the HIV-1/SIVcpz lineage.
Purpose of the Study:
- To investigate the prevalence of cyclophilin A (CypA) binding among diverse lentiviruses.
- To determine the evolutionary significance of the lentivirus-CypA interaction.
Main Methods:
- Yeast two-hybrid assays were used to test for interactions between lentiviral capsid proteins and cyclophilin A (CypA).
- Site-directed mutagenesis was employed on the FIV CA protein to identify key residues for CypA binding.
Main Results:
- Diverse lentiviruses, including Feline Immunodeficiency Virus (FIV) and Simian Immunodeficiency Virus from Tanzania (SIVagmTAN), were found to bind CypA.
- Mutagenesis of FIV CA identified a critical amino acid, homologous to HIV-1 CA Pro90, essential for CypA interaction.
Conclusions:
- Cyclophilin A (CypA) binding is a more common feature among lentiviruses than previously recognized.
- The interaction between lentiviruses and CypA appears to be evolutionarily conserved and important for viral infection.
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