Figure 9.

A, Reactions run in the absence of inhibitor; B, reactions run in the presence of azide; C, reactions run in the presence of nigericin; and D, reactions run in the presence of azide and nigericin. Lanes 1, Intact chloroplasts; lanes 2, isolated thylakoids; lanes 3, stromal fraction; lanes 4, mock protease-treated thylakoids; and lanes 5, protease-treated thylakoids. Intact chloroplasts were preincubated with nigericin (6 μm) and azide (30 mm) (or equivalent volumes of ethanol and water) for 10 min in the dark on ice. Import reactions with precursor OE23 and subsequent fractionations were performed as described in Figure 4, except that an aliquot of thylakoids was removed before the protease treatment. The standard (std) represents 20% of the precursor added to each reaction; the positions of the precursor (p), intermediate (i), and mature (m) proteins are noted.