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.

Upon infection with RV, only some infected Vero cells show at 3 dpi a high p53 signal within the nucleus ( Figure 5A(1) ). While application of the respective inhibitors had no noticeable effect on mitochondrial morphology, differential effects on p53 distribution were observed ( Figure 5B ). (shown in red) and anti-E1 (shown in green) at 3 dpi. Pink colour indicates overlap areas. As a positive control, heat shock (2 h at 43 ¥ C and 24 h at 37 ¥ C) and overnight incubation with 0.003% H 2 O 2 was included; (B) Three days after infection with RV in the presence of pharmacological inhibitors NIM811 (2 µM) at 2 hpi and PFTµ (12.5 µM) at 24 hpi) the expression of p53 was compared to the SC through immunofluorescence analysis with anti-p53 antibody (shown in green) and anti-C protein antibody (shown in white). As a counterstain, mitochondria were labelled with MitoTracker Red CMXRos (shown in red) before fixation. Western blot analysis of (C) a nuclear and (D) a mitochondrial fraction obtained from RV-and mock-infected cells at 3 dpi. Conditions applied are indicated. As a loading control, anti-histone 2B (H2B) and anti-VDAC antibody were applied. HS, heat shock condition; (E) Immunofluorescence analysis of RV-infected Vero cells at 3 dpi, the inset depicts p53 localization (shown in red) outside the nucleus, close to areas of C protein localization (shown in green) and mitochondria (shown in white, stained with MitoTracker DeepRed). SC, solvent control; scale bar, 10 µm.