The Rubella Virus Capsid Is an Anti-Apoptotic Protein that Attenuates the Pore-Forming Ability of Bax
Figure 14
Model for how capsid blocks Bax-dependent apoptosis.
Apoptotic stimuli can induce a conformational change in Bax, which is followed by stable membrane association and oligomerization. The Bax oligomers serve as pores that faciliate efflux of cytochrome c from the mitochondria to the cytoplasm where it initiates downstream apoptotic signaling through the apoptosome. The RV capsid protein binds to Bax before or after it is translocated to mitochondria. Interaction with capsid is followed a conformational change in Bax and subsequent hetero-oligomer formation. However, the Bax-capsid oligomers do not allow efflux of cytochrome c from the mitochondria and apoptosis is blocked.