Defining HIV-1 Vif residues that interact with CBF? by site-directed mutagenesis.

ABSTRACT: Vif is essential for HIV-1 replication in T cells and macrophages. Vif recruits a host ubiquitin ligase complex to promote proteasomal degradation of the APOBEC3 restriction factors by poly-ubiquitination. The cellular transcription cofactor CBF? is required for Vif function by stabilizing the Vif protein and promoting recruitment of a cellular Cullin5-RING ubiquitin ligase complex. Interaction between Vif and CBF? is a promising therapeutic target, but little is known about the interfacial residues. We now demonstrate that Vif conserved residues E88/W89 are crucial for CBF? binding. Substitution of E88/W89 to alanines impaired binding to CBF?, degradation of APOBEC3, and virus infectivity in the presence of APOBEC3 in single-cycle infection. In spreading infection, NL4-3 with Vif E88A/W89A mutation replicated comparably to wild-type virus in permissive CEM-SS cells, but not in multiple APOBEC3 expressing non-permissive CEM cells. These results support a model in which HIV-1 Vif residues E88/W89 may participate in binding CBF?.

SUBMITTER: Matsui Y 

PROVIDER: S-EPMC3936105 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature