The N-terminal region of CAP consists of a coiled-coil and a helical-folded domain (HFD)30,31, whereas the C-terminal region contains two poly-proline-rich domains, a Wiskott–Aldrich-homology 2 (WH2) domain, and a CAP-retinitis pigmentosa (CARP) domain that is comprised of ß-sheets32,33. This evidence concerns the gene CAP1 and retinitis pigmentosa.