Figure 3. BBSome and arl-6 mutant hermaphrodites display defects in amphid sensory organ structure and/or associated glia.

(A) Transmission electron microscopy (TEM) images showing the amphid channels of the indicated genotype in cross section, at the positions of ciliary distal segments (DS) and middle segments (MS)/transition zones (TZ). Arrows point to matrix-filled vesicles (mfv) within the cytoplasm of the sheath glial cell that surrounds the amphid cilia. The extracellular matrix-filled amphid compartment volume is also highlighted. Scale bars; 1 μm (all panels). n = 4 hermaphrodites for WT, n = 1 hermaphrodite for arl-6, bbs-5 and bbs-8 (two amphid organs imaged per hermaphrodite). (B) TEM images of longitudinal sections through the amphid cilia of WT and bbs-8 mutant worms, highlighting the expanded compartment volume and accumulated mfv in the sheath cell (arrows). N = 2 hermaphrodites imaged per genotype, with two amphid organs imaged per hermaphrodite. Question marks denote densities for which identification as either an mfv or an expanded pore region is ambiguous. Scale bars; 1 μm. (C) Cartoon representations of amphid organ ultrastructure in WT and BBSome mutant hermaphrodites, in longitudinal and cross section. Only three cilia are shown in the longitudinal schematics for simplicity.