Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Sci. STKE, 11 January 2005
Vol. 2005, Issue 266, p. tw16
[DOI: 10.1126/stke.2662005tw16]


CELL BIOLOGY New Cofilin Phosphatase

Control of the actin cytoskeleton is critical for many cellular processes, particularly cell motility. The actin-depolymerizing factor cofilin is inhibited by phosphorylation. To better understand its regulation, Gohla et al. used classical protein-purification techniques to isolate a protein with phosphatase activity toward cofilin phosphorylated on serine 3. The enzyme they isolated is a member of the haloacid dehalogenase (HAD) superfamily of phosphotransferases. These phosphatases have an unusual catalytic mechanism and were not previously implicated in serine dephosphorylation in mammals. The phosphatase, which the authors name chronophin (CIN), appears to be a physiologically relevant regulator of cofilin. Overexpression of CIN decreased amounts of phosphocofilin in HeLa cells. Depletion of CIN by RNA interference increased the amount of phosphocofilin, increased the amount of Factin, stabilized membrane protrusions and stress fibers, and caused abnormalities in cell division. The findings place new emphasis on understanding the HAD proteins and suggest that CIN could be a therapeutic target in diseases where control of the actin cytoskeleton is disrupted.

A. Gohla, J. Birkenfeld, G. M. Bokoch, Chronophin, a novel HAD-type serine protein phosphatase, regulates cofilin-dependent actin dynamics. Nat. Cell Biol. 7, 21-29 (2005). [PubMed]

Citation: New Cofilin Phosphatase. Sci. STKE 2005, tw16 (2005).

To Advertise     Find Products

Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882