Extended Data Fig. 1: Macaque pRGC10 mosaic properties suggest the presence of multiple mosaics.
From: An ON-type direction-selective ganglion cell in primate retina
a, Example confocal image showing BNC2, FOXP2 and RBPMS staining of the macaque GCL with pRGC10 (solid circles) and pRGC16 cells (dashed circles) indicated. Confocal stacks of the GCL were 2D median filtered before max z-projection. b, Example of mosaic analysis area showing positions of pRGC10 (blue) and pRGC16 (red) nuclei. Some pRGC10 nuclei are in close proximity suggesting a lack of self-avoidance whereas pRGC16 cells appear more evenly spaced. Dot sizes are not to scale. Region in square ROI is shown in a. c-d, Voronoi domain areas for pRGC10 (c) and pRGC16 (d) from the total area shown in b. e, Voronoi domain regularity index (VDRI) for the real and random simulated (sim) mosaics of pRGC10 (blue) and pRGC16 (red) (n = 4 retinas). The real pRGC10 mosaics are comparable to random simulations whereas the real pRGC16 mosaic is more regular than its random simulation. The grey dashed line indicates the VDRI of a random array of points (~1.9126,58,). Data are mean ± s.d. f, Density recovery profiles (DRPs) of pRGC10 (blue bars) and pRGC16 (red bars). Densities were pooled from retinal pieces of similar size and RGC density (4 regions from n = 3 retinas). Both DRPs show a reduced density at distances closer to the reference cell, seen as a “well-like” zone around each cell in the array where other cells are excluded. The x-axis is mirrored to better visualise this “well”. Black dotted lines indicate the average plateau density and white dotted lines mark an average measure of the lowest part of the “well”, based on real data. The well will be deepest for a single mosaic and become progressively shallower as more mosaics are added27,57. For pRGC16 the density converges at ~21%, which is consistent with the presence of a single mosaic. For pRGC10 the density converges to ~80%, which is consistent with as many as 5 mosaics, however, the data would also be consistent with 3 mosaics, as suggested by the molecular data. Grey lines show DRPs for random simulations with matching numbers of cells and retinal area as the real samples. Overall, the Voronoi domain and DRP analysis indicate that pRGC10 cells have a less regular mosaic structure than pRGC16, consistent with the notion that pRGC10 cells comprise more than one mosaic27. Comparisons in e were with a two-sided Wilcoxon rank sum test. Scale bars: 100 µm (a), 500 µm (b).
