Figure 3.
Nanoscale position of the MEC-2 and MEC-4 MeT channel subunits and MEC-5 collagen in wild-type TRNs.
A
, Schematic cross-section showing the relative positions of the cuticle (gray), four muscle quadrants (green), hypodermis (brown), PLM (green), PLN (blue), and ECM (purple). Structures not to scale. Adapted from WormAtlas (Altun and Hall, 2005).
B
, Electron micrograph showing a cross-section through the cuticle (gray), ECM (purple), PLM (blue), and PLN (green). Cuticle (apical) side is up. Scale bar, 200 nm.
C
, Immunoelectron micrographs of thin sections labeled with anti-MEC-2 (top), anti-MEC-4 (middle), and anti-MEC-5 (bottom). Insets are digitally magnified (2×) views of each label cluster. Filled arrowheads indicate gold beads; open arrowhead indicates a mitochondrion in PLM. Scale bar, 200 nm.
D
, Circumferential position of MEC-2 (top), MEC-4 (middle), and MEC-5 (bottom). Symbol size is proportional to the number of gold beads in a cluster in each section; the smallest symbol corresponds to a single gold bead and the largest symbol corresponds to four gold beads. The average ECM density for the labeled sections is shown as a grayscale annulus around the neurite cross-section.
E
, MEC-5 collagen but not MeT channel subunits exhibit an apical bias. *p < 0.01, χ2 test. The number of labels in each category is indicated in parentheses.