Fig. 3.

In situ hybridization for miR-124 and miR-9 (A–H) in the telencephalic and tectal structures of 7-week-old Nothobranchius furzeri (young adult), and double-staining for doublecortin (DCX)/PCNA andDCX/5-ethynil-2′deoxyuridin (EdU) (I-T). (A) Overview of the right telencephalon in horizontal section where EdU+ cells (green) and miR-124+ cells (red) are visualized. (B) Magnification of the pallial neurogenic niche boxed in A is shown in panel B; the exclusion of miR-124 labeling from the EdU+ cells area is apparent. (C) Overview of the right telencephalon in horizontal section where EdU+ cells (green) and miR9+ cells (red) are visualized. (D) Magnification of the telencephalic subpallial neurogenic area boxed in C. (E) Confocal image of a single optical plane, horizontal section of the pallial neurogenic area. Magnification of the region boxed in E is shown in panel F. (G, H) In situ hybridization labeling in the optic tectum for miR-9 (G) and miR-124 (H). Note the exclusion of miR-124 and miR-9 as well from the germinal layer (arrow) and the complementary labeling pattern of miR-124 and miR-9 in the radial glia (arrowheads). (N–T) Horizontal sections of 7-week-old N. furzeri (young adult) double-labeled for DCX and PCNA (I–Q) or DCX and EdU, 1-2 weeks after intraperitoneal injection (R–T). (I) Horizontal overview of the right telencephalon stained for PCNA (red), DCX (green). (M, N) Magnification of the telencephalic pallial and subpallial neurogenic regions, respectively. Note that in the pallial neurogenic region (L), a strip of DCX+ cells is present immediately adjacent to the PCNA+ cells marginal stratum. In contrast, in the subpallial niche (M) only DCX+ fibers can be detected. (N, O) Representation at low (N) and high (M) magnification of the ventro-posterio tectal margin: a strip of DCX+ neuronal processes (green) is present a few cell diameter medial to the PCNA+ cells (red) in the germinal layer. (P, Q) Representation at low (P) and high (Q) magnification of the retinal ciliary marginal zone: a concentration of DCX+ neuronal processes (red) is present medial from the PCNA+ cells (green) proliferative margin. (R) Representation of the ventro-posterio tectal margin stained for DCX (red) and EdU (green, 1 week postinjection): the strip of EdU+ cells is aligned with the strip of DCX+ processes. (S, T) Representation at low (S) and high (T) magnification of the latero-posterior telencephalic margin stained for DCX (red) and EdU (green, 2 weeks postinjection): the majority of EdU+ cells after 2 weeks correspond with the strip of DCX+ cells. The nuclear DAPI is visualized as blue staining in panel B, D, G, H. (T) Scale bars are directly indicated in the panels: bar in the same for pictures L and M. DCX, doublecortin.