Fig. 9. jing tracheal phenotype. (A) Wild-type stage 10 embryo. Tracheal nuclei are visualized with anti-Trachealess (TRH, red) antibodies and anti-Engrailed (EN, green) references the anterior tracheal border. A subset of tracheal cells express EN (arrows, yellow cells). (B) In jing³ stage 10 homozygous mutant embryos, the number of TRH-positive precursors is reduced. However, the segmental EN-positive stripes and positioning of the placodes appear normal. (C) Wild-type stage 11 embryo stained with anti-TRH (green) and TUNEL (red) showing a rare apoptotic tracheal cell (arrow). (D) Stage 11 jing³ mutant embryo stained with anti-TRH (green) and TUNEL (red). Many apoptotic tracheal cells are present (arrows) and more apoptotic cells surround the pits than in wild-type embryos (arrowhead). (E) Wild-type embryo at stage 12 shows migration of primary branches across EN-positive stripes. A domain of EN-positive tracheal cells encompasses a region of the segmental stripe (bracket). (F) The domain of EN-positive migrating tracheal cells is smaller (bracket) in some stage 12 jing³ mutant segments and absent in others (arrowhead). (G,H) Wild-type stage 15 embryo stained with both anti-TRH (green, G) and TUNEL (red, H). (I,J) jing³ stage 15 homozygous mutant embryo stained with anti-TRH (green, I) and TUNEL (red, J). (I) In jing³ mutant embryos the EGFR-dependent branches are most severely affected. The visceral branch does not form and regions of the dorsal branch are absent (arrows). The number of cells in the DPP-dependent branches (DB and TC) is reduced compared with wild type. (J) By contrast, the overall apoptotic pattern in jing³ mutant embryos is not significantly elevated from wild type. DB, dorsal branch; DT, dorsal trunk; VB, visceral branch; TC, transverse connective; LTa, lateral trunk anterior; LTp, lateral trunk posterior.

Return to article