Fig. 5

Fig. 5 Hindbrain development and other cell migrations are unaffected in trilobite mutants. (A–F), (I), and (J) show dorsal views, and (G) and (H) show side views, with anterior to the left. (A) In an 18-HPF wild-type sibling, hoxb1a is expressed in r4. (B) In a tri mutant, hoxb1a is expressed in a normal fashion in r4. (C) In a 36-HPF wild-type sibling, the 3A10 antibody labels the Mauthner cell bodies in r4 and their axons. (D) In a tri mutant, the Mauthner cells and their axons develop normally. (E) In a 36-HPF wild-type sibling, gata3 is expressed in nVII motor neurons in r6 and r7 (arrowheads), nV neurons in r2 (asterisk), and in nVIII sensory neurons (out-of-focus cells, arrow). (F) In a tri mutant, the gata3-expressing nVII neurons are located in r4 (arrowhead). (G) In a 36-HPF wild-type sibling, an anti-tyrosine hydroxylase antibody labels locus coeruleus (LC) neurons ventrally within r1. (H) In a tri mutant, the LC neurons are found at the same location as in wild-type embryos. (I) In a wild-type sibling, the F59 antibody labels adaxial cells (arrowhead) adjacent to the notochord at the 18-somite stage. By the 30-somite stage, the F59-labeled cells (arrowhead) have migrated radially and laterally away from the notochord and have differentiated into superficial slow muscle fibers. (J) In a tri mutant, the F59-labeled cells (arrowheads) are shorter due to decreased convergence and extension. The location of labeled cells at 18- and 30-somite stages is identical to that in wild-type embryos, indicating that adaxial cell migration occurs normally. oto, otocyst. Scale bar, 100 (A, B, G, H, “30 som” I, J) and 50 μm (C–F, “18 som” I, J).