Fig. 6

The combined expression of prominin-1a and b mimics the distribution of musashi-1 in adult zebrafish brain.

(A–C) Cryosections of 3-month-old adult brain from BrdU-treated zebrafish were processed for ISH using an antisense DIG-labeled probe either against prominin-1a (A; prom1a), prominin-1b (B; prom1b) or musashi-1 (C; msi1). Proliferating cells were observed by immuno-detection of BrdU (brown). Proliferative zones are indicated with Arabic numbers (1 to 16, see below) from rostral to caudal direction along the neuraxis as proposed [41], and position of parasagittal section profiles of the brain is indicated on the cartoon (A) adapted from a standard neuroanatomical atlas of the zebrafish brain by Wulliman and colleagues [104]. The boxed areas in A–C are shown at higher magnification in Figure S2. Black dashed line indicates the border of prosencephalon towards the tegmentum of the brainstem (A). Coloured arrows and asterisks indicate overlapping expression domains of particular genes. Note that major sites of expression of prominin-1a are mainly located in the prosencephalic (rostral) and dorsal mesencephalic (tectal) domain (A), whereas prominin-1b is predominantly found in the rhombencephalic brainstem (caudal) domain (B). Msi1-1–positive cells are confined to all known proliferative zones both in rostral and caudal brain regions (C). CC, crista cerebellaris; CM, corpus mamillare; Cpost, commissura posterior; DIL, diffuse nucleus of the hypothalamic inferior lobe; Rh, rhombencephalon; SD, saccus dorsalis; T, telencephalon; 4V, fourth ventricle. Proliferative zones are: 1, olfactory bulb (OB); 2, ventral telencephalon; 3, dorsal telencephalon; 4, preoptic area; 5, ventral thalamus, 6, habenula; 7, periventricular zone of pretectum; 8, dorsal thalamus; 9, posterior tuberculum; 10, hypothalamus (Hy); 11, tectum opticum; 12, torus longitudinalis; 13, posterior mesencephalic lamina; 14a, molecular layer of valvula and corpus cerebelli (CCe); 14b, lobus caudalis cerebelli; 15, facial and vagal lobes; 16, ventricular zone of the fossa rhomboidea/canalis centralis. Zone 3 is indicated with a hollow number because is not represented on the present section. Black asterisk indicates rhombencephalic brain parenchyma. Scale bars, A–C, 250 μm.