Boomerangs, Bananas and Blimps: Structure and Function of F‑BAR Domains in the Context of the BAR Domain Superfamily
Adam Frost, Vinzenz M. Unger and Pietro De Camilli
Proteins that belong to the BAR (Bin, Amphiphysin, RVS) domain superfamily are alpha‑helical bilayer‑binding modules that have evolved to induce or stabilize membrane curvature during cellular events like endocytosis, cell division and organelle biogenesis. Within the superfamily, a subset of proteins possessing F‑BAR (Fes/CIP4 homology‑BAR) domains play key roles in membrane remodeling and loss‑of‑function mutations in genes coding for F‑BAR proteins are associated with human diseases. Here, we review how F‑BAR domains compare structurally with related members of the BAR domain superfamily and discuss the proposed mechanisms underlying their membrane‑molding activity and regulation. We end by highlighting the functional properties of select F‑BAR domains that were elucidated by electron cryo‑microscopy and 3D reconstruction of these modules while bound to flat and curved membranes.