Figure 5.

Import of preSSU and OEP7 into intact spinach chloroplast under various conditions. [³⁵S]Methionine-labeled preSSU and OEP7 were imported into spinach chloroplasts (lanes 2–15) under various conditions. Lane 1 shows 10% translation product (TP). In the same experiments chloroplasts were preincubated for 10 min with 10 mM spermine (spm, lanes 4 and 5) or spermidine (spd, lanes 6 and 7), with antibodies against Toc75 (α75, lanes 8 and 9), preimmune serum (preα, lanes 10 and 11), or with 10 μg of purified preSSU (pS_ex, lanes 12 and 13). Pore activity was also blocked by 1 mM CuCl₂₊ (Cu²⁺, lanes 14 and 15). After import, chloroplasts were treated with thermolysin (Thr, lanes 3, 5, 7, 9, 11, 13, and 15). A fluorogram is shown.