Fig. 5

Differences in the BMP signaling domains of the medial and apical mesentery region. Immunostaining for pSMAD1/5 (cyan), Tyr-tubulin (gray), and DNA (magenta). A Schematic overview of a mesentery cross-section illustrating morphological domains, highlighted are the retractor muscle region, the medial and the apical (= septal filament) mesentery domains. B Lateral view of the mesentery at the level between subpharynx and gonad region. C–C’ Broad pSMAD1/5 activity in the retractor muscle region. D–D’ pSMAD1/5 is mostly absent from the medial mesentery. E–E’ Individual pSMAD1/5-positive cells at the boundary of the medial mesentery and the septal filament in the reticular tract. F–F’ Individual pSMAD1/5-positive cells in the cnidoglandular tract of the septal filament. All stainings were performed at least two times independently with 3 or more animals imaged. rmr—retractor muscle region, mm—medial mesentery, rt—reticular tract, cgt—cnidoglandular tract. Scale bars 50 µm