Functional Gradients Revealed

Science's STKE  23 Mar 2004:
Vol. 2004, Issue 225, pp. tw110-TW110
DOI: 10.1126/stke.2252004TW110

A variety of physiological processes—from cell motility to the partitioning of chromosomes during cell division—have been explained by the presumed existence of gradients of functionally active proteins. Niethammer et al. have now observed the existence of steady-state phosphorylation gradients of the tubulin-binding protein stathmin. These gradients were present in the lamellipodia of motile cells during interphase and around condensed chromosomes during mitosis. In both of these cases, the gradients are likely to be the result of localized kinase and diffusible phosphatase activities and will contribute to the production of polarized microtubule structures.

P. Niethammer, P. Bastiaens, E. Karsenti, Stathmin-tubulin interaction gradients in motile and mitotic cells. Science 303, 1862-1866 (2004). [Abstract] [Full Text]