FIM-SEM analysis of the spatial distribution of CC transport carriers. (A) Two enlarged block face views of the rod OS and inner segment junction. Black arrows point to the membrane carriers in the inner shafts of the CC; white arrows point to the membrane carriers in the basal body lumens situated exactly beneath the CC inner shaft. Black arrowheads point to the membrane carriers in the outer shaft of the CC. White arrowheads point to a string of vesicles about to enter the outer shaft. The extracellular matrices in the CP are also labeled. (B) A series of ten block face views (labeled one through ten) taken from every other 10-nm section of Additional file 1: Movie 1. White arrows point to a vesicle string in the inner segment that appears to link to the vesicle stream in the CC inner shaft, some of these vesicles had a close spatial relationship with a membrane compartment formed by the elongated tubular network (TN) (frames 4, 7). White arrowheads point to a continuous string of vesicles at the CP base and CC outer shaft. Brackets mark the predicted basal body location. MI mitochondria. Scale bar in nm.