Fig. 3

miR-219 Is Required for Differentiation of Glia and Late-Born Neurons

All images show representative transverse sections through trunk spinal cord with dorsal up.

(A and B) Whereas numerous GFAP⁺ radial glia occupy the spinal cord of a 3 dpf control larva, a miR-219 MO-injected larva has few radial glia except for the most dorsal and ventral regions of spinal cord (brackets). Asterisks mark oligodendrocyte lineage cells.

(C and D) Images showing a deficit of BLBP⁺ radial glia in a miR-219 MO-injected larva compared to control.

(E and F) miR-219 MO-injected larvae appear to have a normal number and distribution of neurons, marked by Elavl3 expression, but fewer oligodendrocyte lineage cells (asterisks) than control larvae.

(G) Graph showing number of Isl⁺ motor neurons in control and miR-219 MO-injected larvae. Data are presented as mean ± SEM (n = 10 sections obtained from 15 larvae per group, with two replicates). p > 0.05, unpaired t test.

(H and I) Confocal images of embryos pulsed with EdU at 1 dpf and fixed at 2 dpf. Numerous Edu⁺ cells are also Elavl3⁺ (arrowheads) in control larvae (H), whereas most EdU label persists within cells lining the spinal cord lumen, and fewer neurons are labeled by EdU in miR-219 MO-injected larva (I).

(J) Graph showing number of Elav3⁺ EdU⁺ neurons in control and miR-219 MO-injected larvae. Data represent mean ± SEM (n = 10 sections obtained from five larvae per group). p < 0.0001, unpaired t test. Scale bar equals 10 μm.