Abstract
Objective: To examine if the intracellular HIV-1 envelope protein (Env) can be trapped by an intracellular chimeric CD4.
Material & Methods: We previously reported a mutant Friend murine leukemia virus Env, FCR, whose intracellular transport was inhibited. Here, a chimera consisting of a surface domain of CD4 and a C-terminal two-thirds of FCR was constructed. HeLa cells expressing the CD4-FCR were transfected with an infectious HIV-1 clone DNA, pNL4-3, and the processing of HIV-1 Env was examined.
Results: Intracellular transport of the CD4-FCR chimera to the cell surface was inhibited as was FCR. When the CD4-FCR-expressing HeLa cells were transfected with pNL4-3, the processing of HIV-1 Env and the infectious HIV-1 production were inhibited. Immunoprecipitation analysis showed binding of the CD4-FCR to the unprocessed HIV-1 Env.
Conclusion: These results suggest that HIV-1 Env could be trapped by the intracellular CD4 in the chimera.
