Regulates the morphogenesis and endocytosis of caveolae (By similarity). Lipid-binding protein that is able to promote the tubulation of the phosphatidic acid-containing membranes it preferentially binds. Plays a role in intracellular vesicle-mediated transport. Involved in the endocytosis of cell-surface receptors like the EGF receptor, contributing to its internalization in the absence of EGF stimulus. Detected at the neck of flask-shaped caveolae. Detected in intestine, cardiac muscle, lung and brain (at protein level). Expressed in all tissues tested, including, gizzard, liver, cardiac muscle, skeletal muscle and skin. The F-BAR domain forms a coiled coil and mediates membrane-binding and membrane tubulation. In the autoinhibited conformation, interaction with the SH3 domain inhibits membrane tubulation mediated by the F-BAR domain (By similarity). Phosphorylated on serine residues. Belongs to the PACSIN family.