FIG. 3.

STS induces VDAC oligomerization in all cell types used. (A) T-REx-293, HeLa, and T47D cells (2.5 mg/ml) were incubated in the absence or presence of STS (1.25 μM; 5 h) and were subjected to cross-linking with EGS (250 μM) and to immunoblotting using anti-VDAC antibodies. The positions of molecular size protein standards are provided. (B) Quantitative analysis of apoptosis (assayed via AcrOr-EthBro staining) (n = 3). (C) T-REx-293, HeLa, and human peripheral blood mononuclear cells (PBMCs; isolated using Ficoll-Paque density gradient centrifugation) (30 and 60 μg) were subjected to immunoblotting using anti-Bax, anti-Bak, anti-Bid, and anti-VDAC antibodies. As a loading control, actin levels in the samples were determined using antiactin antibodies. Note that the increase in the amount of protein loaded was seen for all immunoblotted proteins, except for VDAC, due to the high affinity of the antibodies used, which yielded a saturated signal over 30 μg.