Fig. 4.

atf3 is expressed in a subset of NSCs in the adult pallium. (A) atf3^pos cells (orange dots, UMI values color-coded) on the scRNAseq UMAP of adult quiescent NSCs (blue dots). NSCs closest to activation and/or neurogenesis commitment and NSCs in deep/long quiescence are indicated (Morizet et al., 2024). (B) Expression of atf3 in whole-mount ISH in the adult pallium (dorsal view, anterior left) with the atf3-L probe shown in E. Da, Dl, Dm, Dp, anterior, lateral, median and posterior pallial domains. Arrows point to atf3^pos cells in Dm and Dp. (C1-C4) Optical cross-sections of a Tg(gfap:eGFP) pallium stained in whole-mount for GFP (cyan, IHC), atf3 transcripts (Fast Red) and DAPI (ventricular surface up). Sections are ordered from C1 to C4 along the anteroposterior axis. Red arrows indicate an atf3^pos, GFP^pos cell (asterisk indicates the nucleus). (D1-D4) Optical horizontal sections of the pallium shown in C. D1 to D4 show superficial to deeper locations in sequence. Red arrows indicate an atf3^pos, GFP^pos cell. (E) Atf3 protein isoforms predicted from adult pallial transcripts. DBD, DNA-binding domain; E2-E4, coding exons: L, long; LZ, leucine zipper; S, short. Arrows indicate splice junctions for the L form. Yellow box represents the N terminus of the S form (alternative splicing). Scale bars: 100 µm (B); 5 µm (C1-D4).