THE NEURONAL EF-HAND CA2-BINDING PROTEIN VILIP - INTERACTION WITH CELL-MEMBRANE AND ACTIN-BASED CYTOSKELETON()

VILIP is a member of the visinin/recoverin family of neuronal EF-hand Ca2+-binding proteins. Cell fractionation revealed cytoplasmic, membra ne- and cytoskeleton-associated pools of VILIP. The association with t he cytoskeletal protein fraction is Ca2+-dependent and may be mediated by direct interaction with actin. This is concluded from the observat ions that (i) Ca2+-loaded recombinant VILIP binds actin in an overlay assay; (ii) in the presence of Ca2+, beta-actin co-immunoprecipitates with native VILIP from brain extracts, and (iii) actin and VILIP are c o-localized in PC12 cells stably transfected with VILIP cDNA. The inte raction of VILIP with the cortical cytoskeleton through actin may faci litate a Ca2+-dependent recruitment of VILIP to the cell membrane. (C) 1996 Academic Press. Inc.