Activation of the Mitochondrial Apoptotic Signaling Platform during Rubella Virus Infection

Claus, Claudia; Manssen, Lena; Hübner, Denise; Roßmark, Sarah; Bothe, Viktoria; Petzold, Alice; Große, Claudia; Reins, Mareen; Mankertz, Annette; Frey, Teryl K.; Liebert, Uwe G.

Finally, the intracellular distribution of cyclophilin A (CypA), which is involved in apoptotic processes and acts as a host factor for several viruses [24] , was investigated. Immunofluorescence analysis was performed after permeabilization with two different detergents. Triton X-100 partially dissolves the nuclear membrane, while Tween 20 enables staining of mainly cytoplasmic proteins. Figure 7A highlights that after permeabilization with Tween 20, hardly any differences between mock-and RV-infected Vero cells and Vero cells after overnight incubation with 0.003% hydrogen peroxide are noticeable. This is in contrast to permeabilization with Triton X-100, which shows a clear shift of CypA from a cytoplasmic to a nuclear localization ( Figure 7B(12) ). However, as compared to the mock-infected control, only a slight shift of CypA to the nucleus can be speculated after infection with RV ( Figure 7B(4,8) ). In conclusion, during RV infection, nuclear translocation of Cyp40, but not of CypA, is detectable.