2i2q
Fission Yeast cofilin
Structural highlights
FunctionCOFI_SCHPO Controls reversibly actin polymerization and depolymerization in a pH-sensitive manner. It has the ability to bind G- and F-actin in a 1:1 ratio of cofilin to actin. Binding to F-actin is regulated by tropomyosin. It is the major component of intranuclear and cytoplasmic actin rods. Required for accumulation of actin at the cell division site via depolymerizing actin at the cell ends. In association with myosin II has a role in the assembly of the contractile ring via severing actin filaments. Involved in the maintenance of the contractile ring once formed. In association with profilin and capping protein, has a role in the mitotic reorganization of the actin cytoskeleton.[1] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedADF/cofilins are key regulators of actin dynamics during cellular motility, yet their precise role and mechanism of action are shrouded in ambiguity. Direct observation of actin filaments by evanescent wave microscopy showed that cofilins from fission yeast and human do not increase the rate that pointed ends of actin filaments shorten beyond the rate for ADP-actin subunits, but both cofilins inhibit elongation and subunit dissociation at barbed ends. Direct observation also showed that cofilins from fission yeast, Acanthamoeba, and human sever actin filaments optimally at low-cofilin binding densities well below their K(d)s, but not at high binding densities. High concentrations of cofilin nucleate actin assembly. Thus, the action of cofilins in cells will depend on the local concentration of active cofilins: low concentrations favor severing, whereas high concentrations favor nucleation. These results establish a clear paradigm for actin turnover by cofilin in cells. Mechanism of actin filament turnover by severing and nucleation at different concentrations of ADF/cofilin.,Andrianantoandro E, Pollard TD Mol Cell. 2006 Oct 6;24(1):13-23. PMID:17018289[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
