While activation of BAX/BAK by BH3-only molecules (BH3s) is essential for mitochondrial apoptosis, the underlying mechanisms remain unsettled. Here we demonstrate that BAX undergoes stepwise structural reorganization leading to mitochondrial targeting and homo-oligomerization. The alpha1 helix of BAX keeps the alpha9 helix engaged in the dimerization pocket, rendering BAX as a monomer in cytoso...

BACKGROUND Bax and Bcl-2 are the major members of Bcl-2 family whose play a key role in tumor progression or inhibition of intrinsic apoptotic pathway triggered by mitochondrial dysfunction. Therefore, the balance between pro- and anti-apoptotic members of this family can determine the cellular fate. METHODS In this study, the relative level of mRNA expression of Bax and Bcl-2 genes was deter...

The Bcl-2 family proteins Bax and Bak are essential for the execution of many apoptotic programs. During apoptosis, Bax translocates to the mitochondria and mediates the permeabilization of the outer membrane, thereby facilitating the release of pro-apoptotic proteins. Yet the mechanistic details of the Bax-induced membrane permeabilization have so far remained elusive. Here, we demonstrate tha...

In mitochondrion-dependent type II apoptosis, BH3-interacting domain death agonist (BID) and BCL-2-associated X protein (BAX) promote death ligand and receptor-mediated cell death. In porcine ovaries, the levels of BID and BAX increase in follicular granulosa cells during atresia. In the present study, to confirm the pro-apoptotic activity of BID and BAX in granulosa cells, we examined the effe...

Previously, we have shown the loss of anti-Bax function in Creutzfeldt Jakob disease (CJD)-associated prion protein (PrP) mutants that are unable to generate cytosolic PrP (CyPrP). To determine if the anti-Bax function of PrP modulates the manifestation of prion diseases, we further investigated the anti-Bax function of eight familial Gerstmann-Sträussler-Scheinker Syndrome (GSS)-associated PrP...

Previously we reported that proteasome inhibitors were able to overcome Bcl-2-mediated protection from apoptosis. Here we show that inhibition of the proteasome activity in Bcl-2-overexpressing cells accumulates the proapoptotic Bax protein to mitochondria/cytoplasm, where it interacts to Bcl-2 protein. This event was followed by release of mitochondrial cytochrome c into the cytosol and activa...

The role of Bax and Bak, 2 proapoptotic proteins of the Bcl-2 family, was analyzed in primary B-cell chronic lymphocytic leukemia (CLL) cells following in vitro treatment with fludarabine, dexamethasone, or the combination of fludarabine with cyclophosphamide and mitoxantrone (FCM). A strong correlation was found between the number of apoptotic cells and the percentage of cells stained with ant...

Sustained activation of AMPA and kainate receptors in rat oligodendrocytes induces cytosolic calcium overload, mitochondrial depolarization, and an increase of reactive oxygen species, resulting in cell death. Here, we provide evidence that Bax, a proapoptotic member of the Bcl-2 protein family, is involved in excitotoxic apoptotic death of oligodendrocytes and that calpain mediates Bax activat...

In the adult mouse tongue, an average of 11% of the gustatory receptor cells are replaced each day. In investigating homeostatic cell death mechanisms in gustatory renewing epithelium, we observed that taste receptor cells were selectively immunopositive for the bcl-2 family death factor, Bax, and for the protease Caspase-2 (Nedd2/Ich1). We determined that 8-10% of the taste receptor cells of t...