Fig. 6. Mistargeting is rescued by removal of C-terminal lipids. (A) Effect of C-terminal deletions on yeast Ykt6p mislocalization mutants. The last five amino acid residues (CCIIM) were deleted from yeast Ykt6p mislocalization mutants and expressed in PC12 cells (Table 1). The subcellular localization of each mutant and endogenous rat Ykt6 was examined by double-label fluorescence microscopy using anti-Myc antibody (9E10) and anti-rat-Ykt6 antibody. (Top left) Myc-tagged yeast Ykt6p F39E with CCIIM deletion. (Bottom left) R50E/R56E with CCIIM deletion. Arrows point to punctate structures where the mutants and endogenous rat Ykt6 colocalize (overlaps were 31% and 18%, respectively). Identical results were obtained when CCIIM was deleted from other mislocalization mutants (Table 1). Scale bar, 10 µm. (B) Effect of C-terminal mutations on rat-Ykt6 mislocalization mutants. Rat Ykt6 mutants that have mutations in both the longin domain and the C-terminal lipidation motif were created (Table 2). Mutants were expressed in PC12 cells and the subcellular localization of each mutant was examined by fluorescence microscopy using anti-Myc antibody and FITC-labeled secondary antibody. Mutations to the longin domain are indicated at the left and mutations to the C-terminus are indicated at the top. Scale bar, 10 µm.