Fig. 3. The defined orientation of the flagellar pocket collar is randomised in IFT^RNAi mutants. (A) Scanning electron micrograph of a wild-type cell extracted with cold Triton X-100. The white rectangle indicates the position of the magnified area shown on the right. The FPC and the FAZ filament are indicated by white arrows and arrowheads, respectively. (B) An intact wild-type cell examined by scanning electron microscopy. The magnified area shows the region where the flagellum emerges from the cell body. The shape of the FPC is visible underneath the membrane (white arrows). (C) Images of IFT140^RNAi cells (a-c) induced for 72 hours and treated with cold Triton X-100 as in A. The FPC associated with the short flagellum appears less elaborate and its orientation relative to the main axis of the cell is variable. (D) A non-extracted IFT140^RNAi cell after induction of silencing for 72 hours. The shape of the FPC is clearly recognisable but its orientation is not perpendicular to the main axis of the cell.