Figure 7

Tuning of Phototransduction Cascade Elevates SZ Baseline

(A) UV cone RNA sequencing (RNA-seq) workflow. Retinas from 7 dpf zebrafish Tg(opn1sw1:GFP) were dissected and separated into SZ and non-SZ. After cell dissociation, UV cones were FACS sorted and immediately flash frozen. Samples were then subjected to library preparation for next-generation sequencing.

(B and C) All detected genes in UV cones ranked by expression label, with phototransduction genes highlighted (B), and zoom in to the top 200 genes (C). The two most highly expressed genes are both non-protein-coding genes; therefore, UV opsin is the highest expressed protein-coding gene.

(D) Mean gene expression ratio between SZ and non-SZ batches, with phototransduction genes highlighted.

(E) As in (D), but normalized to UV-opsin expression level in each batch and zoomed in to high expression phototransduction targets. Green and gray markers denote activators and repressors of the photo-response, respectively. Error bars represent SEM.

(F) Schematic of phototransduction based on Yau and Hardie (2009), with activators and repressors denoted in green and gray, respectively.

(G) Simulated current response of SZ and non-SZ UV cones to 100% dark and light contrasts from a 50% contrast background based on Invergo et al. (2014). Non-SZ was based on default model parameters, while SZ uses relatively scaled parameters according to gene expression ratios as in (E).

(H) Effects of expression changes of individual phototransduction components compared to non-SZ.

(I) Mean calcium responses to a flash of light from darkness in SZ, nasal, and dorsal UV cones from Figure 4E.

(J) Output of full phototransduction model to an equivalent stimulus between SZ and non-SZ batches.

(K) Full model output to a series of increasing amplitude 5-ms light flashes from darkness for SZ and non-SZ batches.

(L and M) Stimulus-response data from SZ and average of non-SZ data (N+D+V) from Figure 3H (L) and corresponding quantification of the phototransduction model output (K) (M).