HCV NS5A and IRF9 compete for CypA binding.

ABSTRACT:

Background & aims

Cyclophilin A (CypA) is vital for HCV replication. Cyp inhibitors successfully decrease viral loads in HCV-infected patients. However, their mechanisms of action remain unknown. Since interferon (IFN) can also suppress HCV replication, we asked whether a link between CypA and the IFN response exists.

Methods

We used cellular and recombinant pulldown approaches to investigate the possibility of a specific association of CypA with host ligands.

Results

We found for the first time that CypA binds to a major component of the IFN response - the IFN regulatory factor 9 (IRF9). IRF9 is the DNA-binding component of the transcriptional IFN-stimulated gene factor 3 (ISGF3). CypA binds directly to IRF9 via its peptidyl-prolyl isomerase (PPIase) pocket. Cyp inhi

SUBMITTER: Bobardt M 

PROVIDER: S-EPMC3527675 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature