Korzh et al., 1993 - Zebrafish primary neurons initiate expression of the LIM homeodomain protein Isl-1 at the end of gastrulation. Development (Cambridge, England)   118:417-425

Fig. 1 Patterns of expression of Isl-1 immunoreactivity in early zebrafish embryos. (A) 13 hpf; (B) 17 hpf; (C-E) 18 hpf. a, anterior; p, posterior; agc, anterior group of cells; tg, trigeminal ganglia; mn, primary motor neurons; rb, Rohon-Beard cells; in, interneurons; vr, ventrorostral cluster; dr, dorsorostral cluster; e, epiphysis; allg, anterior lateral line ganglia; d, diencephalon; t, telencephalon; pc, neurons of nucleus of posterior commissure. In E the solid lines represent segment borders. Bars, 50 μm.

Fig. 2 Expression pattern of Isl-1 at the early neurulation stage. (A) The anterior group of cells at 12 hpf; (B) the region where the first somites will form, 12 hpf; (C) the same region as in B but with a lower magnification; (D) as in C but more posteriorly; (E) cross section through midpart of embryo at 10 hpf; (F) cross section through midpart of embryo at 12 hpf. mn, primary motor neurons; rb, Rohon- Beard cells. Bars, 50 μm.

EXPRESSION / LABELING:
Antibody:
Fish:
Anatomical Terms:
Stage Range: Bud to 5-9 somites

Fig. 3 Expression pattern of Isl-1 at 22 hpf. (A) Cross section through the anterior part of the brain in front of the eyes; (B) cross section through the anterior brain at the level of the epiphysis; (C) cross section at the level of the nucleus of posterior commissure; (D) cross section of the midbrain; (E) cross section of the 4th segment of the hindbrain; (F) cross section through the spinal cord of a double stained (anti-tubulin and anti-Isl-1) embryo. ag, acoustic ganglion; vr, ventrorostral cluster; dr, dorsorostral cluster; ob, olfactory bulb; pc, nucleus of posterior commissure; vc, ventrocaudal cluster. Bar, 50 μm.

Fig. 4 Isl-1 is expressed in neurons with long axons. (A) Nuclei of the trigeminal ganglion and the anterior part of dorsolateral fascicle (DLF) visualized in a 28 hpf embryo by whole-mount immunostaining with anti-Isl-1 and anti-HNK-1 antibodies; (B) Rohon-Beard nuclei in the spinal cord and the posterior part of dorsolateral fascicle visualized in whole-mount immunostaing using anti-Isl-1 and anti- HNK-1 antibodies (28 hpf); (C,D) whole-mount immunostaining of a 22 hpf embryo using anti-Isl-1 and anti-acetylated a-tubulin antibodies (eyes and yolk were removed before staining). tg, trigeminal ganglion; dr, dorsorostral cluster; vr, ventrorostral cluster; vc, ventrocaudal cluster; ob, olfactory bulb; e, epiphysis; nPC, nucleus of posterior commissure; PC, posterior commissure; DVT, dorsoventral tract; SOP, supra-optic tract; TPOC, tract of postoptic commissure; +, Isl-1-positive cell nuclei in the region where SOT and TPOC fasciculate. Bars, 50 μm.

Fig. 5 Restricted pattern of Isl-1 expression in zebrafish larvae at 72 hpf.(A) Cross section through the brain at the level of eyes; (B) cross section through the spinal cord. e, epiphysis; vd, ventral diencephalon; vgc, ventral group of cells; p, putative enteroendocrine cells dispersed in the intestinal wall; rb, Rohon-Beard cells; mn, motor neurons. Bar, 50 μm.

Acknowledgments:
ZFIN wishes to thank the journal Development (Cambridge, England) for permission to reproduce figures from this article. Please note that this material may be protected by copyright.