Fig. 1 flh is expressed in embryos with an open neural tube. In (A, E) WT and (B, F) sqt mutant embryos with closed neural tubes, the pineal precursors (p, white arrowheads) form a single, oval domain that spans the dorsal midline (dotted lines) separating the left (L) and right (R) sides of the epithalamus. (C) In sqt embryos with mild open neural tube defects, the pineal precursors still span the dorsal midline of the brain, but the pineal anlage is elongated along the left–right axis. (D, G, H) In sqt and cyc; sqt embryos with a severe open neural tube phenotypes, the pineal precursors are present in two divided domains on the left and right sides of the brain. Dorsal views of the epithalamus in (A–D) live or (E–H) fixed embryos, anterior to the top. Scale bar=20 μm.
Reprinted from Developmental Biology, 374(2), Lu, P.N., Lund, C., Khuansuwan, S., Schumann, A., Harney-Tolo, M., Gamse, J.T., and Liang, J.O., Failure in closure of the anterior neural tube causes left isomerization of the zebrafish epithalamus, 333-344, Copyright (2013) with permission from Elsevier. Full text @ Dev. Biol.