Molecular composition of the AIS coat. Immunogold PREM of indicated AIS proteins in DIV14 neurons. (Low Mag) Regions of dense AIS coats along the main axon shaft showing immunogold staining (yellow) of AIS proteins. Bar, 100 nm. (High Mag) Galleries of immunogold-stained AIS proteins in sparse or stretched regions of the coat. Duplicate images are pseudocolored to show gold particles (12 nm; yellow,) associated with putative spectrin βIV (violet), neurofascin (green), NrCAM (orange), and Nav (blue) proteins. A cluster of three putative Nav proteins (blue, purple, and magenta) associated with two gold particles is shown in the top right panel. Yellow arrows indicate donut-like shapes with slightly larger diameter than Nav, possibly representing other ion channels in the AIS. Several putative ion channels are in close proximity to an NrCAM-positive filament (enlarged in bottom panel from red box in the panel immediately above). Putative Nav-containing AnkG globular cluster is pseudocolored in red to highlight its close proximity to spectrin βIV (bottom left corner). Bars, 20 nm.