Fig. 2

Anisotropic Retinal Structure

(A) 3D confocal stack taken across the entire retina of an 8 dpf larva (Tg(Opn1sw1:GFP)) with all U-cones fluorescently labeled was used for semi-automated quantification of cone densities across the retina (STAR Methods).

(B) Average densities of all four cone types and rods across the retina, based on n = 6 (R), 6 (G), 5 (B), 5 (U), and 4 (rods) retinas (Tg(thrb:Tomato) for R; zpr-1 antibody staining for G; Tg(−3.5opn1sw2:mCherry) for B; Tg(opn1sw1:GFP) for U; and Tg(xops:ntr-mCherry) for rod). Color scales: 0 (white)–35,000 (black) cones mm⁻² or 0–9,000 rods mm⁻². D, dorsal; N, nasal; T, temporal; V, ventral.

(C–E) To compare cone distributions across retinal positions (C and D), we computed densities at sagittal plane approximately aligned with the back surface of the lens (E; STAR Methods). This plane projects in a ∼130° cone from the eye center, with eyes rotated ∼36.5° forward during prey capture (18.5° at rest; Figures S2A and S2B). Cone and rod densities across the plane are defined in (E) on a linear scale of the fish’s egocentric visual field. Dashed lines indicate the forward and outward horizon. (D) is as (C), plotted in polar coordinates relative to the body of the fish as indicated.

(F) Whole-eye immunostaining of an 8 dpf Tg(−1.8ctbp2:SyGCaMP6) larvae labeled against GFP (bipolar cell [BC] terminals, green), choline acetyltransferase (ChAT) (cholinergic amacrine cells, cyan), and protein kinase C alpha (PKCα) (on-BCs, magenta). Shown is the same sagittal section used in (F)–(H). PKCα-stained BC somata are only faintly visible as the chosen equalization was tuned to highlight the much more strongly labeled synaptic terminals in the strike zone. The scale bar represents 50 μm. GCL, ganglion cell layer; INL, inner nuclear layer; IPL, inner plexiform layer; OPL, outer plexiform layer.

(G–J) Higher magnification sections from (F) showing the IPL at different positions across the eye as indicated. For clarity, GFP/PKCα (G₁–J₁) and ChAT/PKCα (G₂–J₂) are shown separately. Looking up (G), “strike zone” (H), looking down (I), and outward horizon (J). The scale bar represents 5 μm.

(K) Mean IPL thickness across n = 5 whole-eye immunostainings as in (F).

(L) Mean signal in the three fluorescence channels as above.

See also Figure S2.