Coronin 1B (CORO1B)

Members of the coronin family, such as CORO1B, are WD repeat-containing actin-binding proteins that regulate cell motility.The protein contains WD40 repeats in its N-terminal half and a coiled-coil region at its C terminus. Fluorescence-tagged CORO1B localized predominantly to the leading edge of transfected fibroblasts, with some localization along actin stress fibers.Rat fibroblasts expressing human CORO1B with a ser2-to-ala mutation showed enhanced ruffling in response to phorbol esters and increased speed in single-cell tracking assays. Cells expressing a constitutively active CORO1B mutant (ser2 to asp) had attenuated ruffling and slower cell speed in response to phorbol esters. CORO1B interacted with the ARP2/3 complex, and the interaction was regulated by PKC phosphorylation of CORO1B.