Naslov
Domain analysis of cortexillin I: actin bundling, PIP2-binding and the rescue of cytokinesis

Autori
Stock, A. ; Steinmetz, M.O. ; Janmey, P.A. ; Aebi, U. ; Gerisch, G. ; Kammerer, R.A. ; Weber, Igor ; Faix, J.

Izvornik
EMBO Journal (0261-4189) 18 (1999), 19; 5274-5284

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Sažetak
Cortexillins are actin-bundling proteins that form a parallel two-stranded coiled-coil rod. Actin-binding domains of the alpha-actinin/spectrin type are located N-terminal to the rod and unique sequence elements are found in the C-terminal region. Domain analysis ill vitro revealed that the N-terminal domains are not responsible for the strong actin-filament bundling activity of cortexillin I. The strongest activity resides in the C-terminal region. Phosphatidylinositol 4, 5-bisphosphate (PIP2) suppresses this bundling activity by binding to a C-terminal nonapeptide sequence. These data define a new PIP2-regulated actin-bundling site. In vivo the PIP2-binding motif enhances localization of a C-terminal cortexillin I fragment to the cell cortex and improves the rescue of cytokinesis. This motif is not required, however, for translocation to the cleavage furrow. A model is presented proposing that cortexillin translocation is based on a mitotic cycle of polar actin polymerization and midzone depolymerization.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA