Figure 7.

Insertion of Arabidopsis PMP22 into isolated peroxisomes. Radiolabeled PMP22 was prepared by in vitro transcription and translation in wheat germ lysate and incubated with peroxisomes isolated from 3-d postimbibition sunflower cotyledons (see Methods). Lane 1, 40% of the translation product added to the other reactions; lane 2, import reaction carried out in the presence of the ATP-regeneration system; lane 3, import in the presence of the ATP-regeneration system followed by protease treatment; lane 4, same as lane 3 but in buffer containing 1% Triton X-100 and 250 mm NaCl before the addition of protease; lane 5, import in the absence of ATP and the ATP-regenerating system; lane 6, import in the absence of ATP and the ATP-regenerating system followed by treatment with protease; lane 7, same as lane 3 but no peroxisomes were added to the import assay; lane 8, same as lane 2 but glyoxysomes were replaced with 50 μg of washed red blood cells from calf ascites; lane 9, same as lane 8 but treated with protease; lanes 10 to 15, Na₂CO₃ (pH 11.0) treated pellets and supernatants derived from import reactions (lane 10 is the pellet and lane 11 the supernatant of the import reaction in lane 2, lane 12 is the pellet and lane 13 the supernatant of the import reaction in lane 3; and lane 14 is the pellet and lane 15 the supernatant of the import reaction in lane 5).