Actin filament binding protein; regulates actin filament capping by recruiting capping protein to endocytic sites and to the cytokinetic actin ring; interacts with the capping protein complex; adapter that links synaptojanins, Inp52p and Inp53p, to the cortical actin cytoskeleton; contains two WH2-like actin binding domains and a C-terminal capping protein interaction (CPI) motif