Figure 2.

Requirements for recycling. Except where indicated, cells of the indicated genotypes expressing GFP-Snc1p were imaged (live). The tlg1 cells were labeled with FM4-64 for 2 h before imaging in separate channels to reveal GFP and vacuolar membranes. In this pair of images, and in subsequent figures, arrows indicate identical positions in the two channels. For vps5 s6, sec21, and cop1 cells, incubation at 37°C was for 1 h. Snc-sso refers to a version of GFP-Snc1p whose transmembrane domain was replaced by that of Sso1p, a change that prevents retrieval of the protein from the endocytic pathway (see RESULTS). The vps4 cells expressing this protein were labeled with FM4-64, and both images are shown. Note the class E compartments containing both GFP and FM4-64 (arrows).