Positive prenylated probes are enriched in the cell body PM, perinuclear membranes, and the OS–IS junction. (A) Representative confocal images. Scale bars, 10 µm. Arrowheads: OS–IS junction. (B) 3D renderings of the Far+8 rod shown in A, at different angles (see angle indicators). Green: 50th percentile, red: 90th percentile intensities. White arrowheads: CPs (Videos 1, 2, and 3). Scale bar, 5 µm. (C) Confocal images of broken OS–IS showing fluorescence-containing CPs separated from OS. Scale bars, 5 µm. (D) OS–IS junction enrichment width estimate. Upper panel: Confocal image of Far+8 rod in A with OS–IS junction expanded. Scale bar, 5 µm. Middle panel: Fluorescence intensities as a function of axial distance; zero is the OS–IS junction. Arrowheads show half maximum fluorescence. Bottom panel, Junction widths for Far+8 and GG+8 cells were not different as determined by two-tailed T test assuming equal variance. Box-whisker plot as described in Fig. 2. n for each construct: Far+8, 9; and GG+8, 12. (E) Fluorescence as a function of distance within the OS. Left panels: Representative profiles from positive prenylated probes. Right panels: OS distributions of other PMPs. (F) FRAP of Far+8 in the synapse. Red box: Spherule region of interest (ROI); yellow box: OS–IS junction ROI. Scale bar, 5 µm. (G) Time course of synapse fluorescence recovery and OS–IS junction fluorescence loss.