Figure 4 of Regus-Leidig, Mol Vis 2010; 16:2690-2700.

Figure 4. Arciform density/plasma membrane proteins are stable components at the ribbon synaptic site. A-D: Representative images of the outer plexiform layer with the photoreceptor ribbon synapses double labeled for RIBEYE (green) and components of the arciform density/plasma membrane compartment (red) from untreated (A, C) and EGTA-treated (B, D) retinae. The arciform density/plasma membrane proteins RIM2 (B) and the L-type Ca2+ channel subunit Cacna1f (D) often show a horseshoe-shaped labeling under EGTA treatment, when RIBEYE has already disintegrated into aggregates. Scale bar: 5 µm.