Figure 1. ON and OFF Starburst Amacrine Cells are Transcriptionally Distinct Subtypes Distinguished by Fezf1. See alsoFigure S1.

(A) Development of SACs. ONBL/INBL: outer/inner neuroblastic layer; OPL/OPL: outer/inner plexiform layer; INL: inner nuclear layer; GCL: ganglion cell layer; BC: bipolar cell; ooDSGC: ON-OFF direction-selective ganglion cell.

(B) t-distributed stochastic neighbor embedding (tSNE) visualization of 136 SACs sequenced at E16.

(C) Dotplot of select genes expressed by clusters 1 and 2 of the E16 SAC dataset. Megf10, Sox2, Isl1, and Slc18a3 are known SAC marker genes (left). Genes of interest are largely selected from the P0 differentially expressed (DE) gene list. DE genes that achieve statistical significance are in bold.

(D) Violin plot of Fezf1 expression in the two E16 SAC clusters.

(E-G) Same as B-D for 2,055 SACs sequenced at P0.

(H-J) Double fluorescence in situ hybridization (FISH) using probes against Fezf1 (magenta) and Megf10 or CHAT (green) to label SACs in E15.5 and P0 mouse retina (H), P0 marmoset retina (I) and the peripheral (top) and central (bottom) regions of E8 chicken retina (J). Among Megf10- or CHAT-positive SACs, Fezf1-positive cells are ON SACs while negatives are OFF SACs. FEZF1- and CHAT-positive cells in marmoset are ON SACs.

(K) Model of Fezf1-expressing SAC soma position before and after ON and OFF SAC soma segregation.

Scale bars are 20μm. SAC somas are outlined by circles, and white dashed lines indicate the ONBL and INBL border.