Fig. 6. Remodeling of E-cadherin (DE-cad) contacts and associated F-actin during anastomosis. (A-E) Tracheal cells (membranes outlined in green) in adjacent branches abut via the fusion cells (asterisks) and form a DE-cadherin contact (red, arrows) and associated F-actin (blue). (F-J) Remodeling of the E-cadherin contact (arrows) from a spot found in the anterior fusion cell (F,G) to one spanning both (M), and then a ring (I,J). (K-O) Membrane remodeling at the contact site. Initially (K,L), the fusion cells (asterisks) are round and their apical surfaces only face the existing lumens. As the contact matures (H), membrane is detected (arrow), spanning the fusion cells and connecting with these existing apical surfaces. This membranous compartment (arrow in N) expands as the cadherin contact becomes a ring (O). (P-T) An F-actin-rich track initiates at the site of E-cadherin contact (arrow in P) and lengthens to span the fusion cells (Q,R). As the central cadherin ring forms, the track disappears and F-actin is enriched at cadherin contacts (S,T). Scale bar: 10 µm.