Fig. 4. Shot and F-actin form a cytoskeletal track associated with the E-cadherin (DE-cad) contacts between fusion cells. (A-T) Stage 13, wild-type embryos. (A-E) Remodeling of the fusion cell E-cadherin (red) contact (arrows) and associated Shot-GFP (green) and F-actin (blue) during anastomosis. (F) E-cadherin accumulates in a spot at the interface between the fusion cells. (G,H) Elongation of the E-cadherin spot. (I) Contraction of the E-cadherin contact into a ring. (J) The three rings of E-cadherin at the anastomosis site. (K-O) Shot L(A)-GFP is associated with the E-cadherin contact during anastomosis. (P-T) A track of F-actin forms, associated with the E-cadherin contact, that grows to span the two fusion cells (S). (T) The F-actin track becomes a ring. (U-X) C-Shot L-GFP (green in X) and F-actin (blue in X) accumulate at the E-cadherin (red in X) contact (arrow).