Pcdh9 and Pcdh17 expression in 24 hpf zebrafish embryos. All panels show whole mount embryos labeled with Pcdh9 cRNA (A–D, I–L) or Pcdh17 cRNA probes (E–H, M–P). (A and E) Lateral views of the anterior half of the embryos (anterior toward the lower left corner, and dorsal to the upper left corner). (B, C, F and G) Lateral views (anterior to the left and dorsal up) of the head, with (B and F) the fore- and midbrains, and (C and G) showing the hindbrain region. (D and H) Lateral views (anterior to the left and dorsal up) of whole mount eyes. (I, J and M) Frontal views (dorsal up) of embryo heads with focusing planes at the diencephalon level. (K and O) Dorsal views of the hindbrain region (anterior to the left). (L, N and P) Lateral views from the mid-trunk region (anterior to the left and dorsal up). The arrowheads in (B, F, I and M) point to the more anteroventrally located Pcdh9 or Pcdh17 expressing cluster, while the arrows in (B and J) point to the more posterodorsally located Pcdh9 expressing cluster in the anteroventral diencephalon. Asterisks in (C and K) indicate clusters of Pcdh9 expressing cells in the hindbrain. Arrows in (G, H, N, O and P) point to Pcdh17 expressing cells. Abbreviations: c, cerebellum; di, diencephalon; ey, eye; h, hindbrain; hd, head; le, lens; nc, notochord; or, optic recess; ot, optic tectum; ov, otic vesicle; p, pineal organ; rpe, retinal pigmented epithelium; sag, statoacoustic ganglion; sc, spinal cord; te, telencephalon; teg, tegmentum, y, yolk.