FIG. 6.

In contrast to cytochrome c release, Bid-induced insertion of Bax does not require the presence of Mg²⁺. (A) Mitochondria from HeLa cells were incubated with 100 nM Bid for 15 min at 30°C in the presence or absence of 2.5 mM MgCl₂ or MnCl₂ before analysis of Bax insertion into membranes. (B) Mitochondria were incubated in the presence or absence of 100 nM Bid and various salts including MgCl₂ (2.5 mM), MnCl₂ (2.5 mM), KCl (5 mM), NaCl (5 mM), and LiCl (5 mM). Both supernatants and mitochondrial pellets were analyzed for cytochrome c release. Ctl., control; Att., attached (alkali sensitive); Ins., inserted (alkali resistant); Cyt. c, cytochrome c.