Overexpression of SRGP-1::GFP induces F-BAR–dependent bending at cell–cell junctions. (A and B) Overexpressed JAC-1/p120-catenin (A) and HMP-1 (B) appear as straight lines at AJs. (C) Overexpressed SRGP-1 has a wavy appearance. (D–G) The wavy appearance remains upon RhoGAP domain deletion (D) but is abolished when the F-BAR domain is deleted (E). The F-BAR domain alone has a mild effect on membranes (F). However, coupled with the junctional targeting sequence, it becomes very potent in deforming junctions (G). Insets show magnification of the indicated areas. (H) The N-terminal half of SRGP-1 (containing the F-BAR domain and junctional targeting domain) tagged with 6× His does not bind significantly to GST alone (left), but it does binds strongly to the C-terminal half of SRGP-1 tagged with GST (middle), which on its own does not degrade to give a similar band (right). (I–K) Immunostaining of SRGP-1::GFP embryos with an αHMR-1 antibody (I) and embryos coexpressing SRGP-1::mCherry and HMP-1::GFP (J) show a high degree of colocalization between cadherin–catenin complex components and SRGP-1. In contrast, DLG-1::dsRed is not perturbed by SRGP-1::GFP expression and does not colocalize in induced projections (K).