Fig. 2

Comparison of Tc ASH and Tc ato expression patterns in the developing peripheral nervous system. Light micrographs of flat preparations stained with DIG labelled RNA probes. Anterior is towards the top. Open arrowheads: tracheal pits. a, b Tc ASH and Tc ato expression pattern in whole embryos at NS13. Arrows: expression in the antennae. Tc ato is strongly expressed in the whole tip of the antenna, while Tc ASH is expressed in small groups of cells. Small arrowheads: expression in the legs. Large arrows: expression in the lateral body wall. c In the three thoracic segments, Tc ASH is expressed in three dorso-ventral rows (anterior-dorsal (a), medio-dorsal (m), and posterior-dorsal (p)) dorsal to the appendages, covering all areas of ESOs development. Arrows: medio-lateral expression domain in t2 and t3 corresponding to an area which is devoid of ESOs in 1st stage larvae. Transcripts are visible in the legs. d In the thorax, Tc ato is expressed in a single group of cells at the posterior base of the legs, corresponding to plCSM, and a few groups in the legs (arrows). At approximately the same position, the Tc ato positive plTSO cluster is visible in the abdominal segments. Arrowhead in t1: additional Tc ato positive cluster. e In the most dorsal part of the abdominal segments (bracket), Tc ASH is expressed in many cells, covering the area from which the pdCSGs and BSMs arise. Tc ASH is also expressed in the ventro-lateral areas from which the three TSOs arise and in the ventral neuroectoderm (asterisk). f Tc ato is expressed in pdCSG2 and the three TSOs in the abdominal segments. For abbreviations, see Fig. 1. Scale bar in a, 100 μm in a, b; 25 μm in c, d, e, f