A. The oxidized mitochondria with radioactive single, double, or triple-cysteine Bax proteins were prepared and analyzed by non-reducing or reducing SDS-PAGE as in Figure 1B. Protein standards, Bax monomers and disulfide-linked Bax homodimers are also indicated as in Figure 1B. Closed triangles indicate disulfide-linked higher order Bax homo-oligomers. Open triangles indicate a background band that could not be reduced, and hence is not a disulfide-linked complex. 