Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2003 Aug 15;278(33):31020-3.
doi: 10.1074/jbc.M301179200. Epub 2003 May 16.

Localized cdc42 activation, detected using a novel assay, mediates microtubule organizing center positioning in endothelial cells in response to fluid shear stress

Affiliations
Free article

Localized cdc42 activation, detected using a novel assay, mediates microtubule organizing center positioning in endothelial cells in response to fluid shear stress

Eleni Tzima et al. J Biol Chem. .
Free article

Abstract

Fluid flow regulates morphology, physiology, and pathophysiology of vascular endothelial cells (reviewed in Ref. 1). The small GTPase Cdc42 mediates polarity in several systems including migrating cells and early embryos, which involve reorientation of the microtubule organizing center (MTOC) and Golgi apparatus toward the direction of movement. Here, we show that Cdc42 is activated by fluid shear stress and that activation is a consequence of integrins binding to extracellular matrix. A novel fluorescence energy transfer assay to visualize Cdc42 activation in single cells shows that Cdc42 activity is polarized in the direction of flow. Localized activation of Cdc42 as well as the activity of Par6 and protein kinase Czeta direct the reorientation of the MTOC to a position on the downstream side of the nucleus relative to the direction of flow. Thus, shear-stimulated integrin dynamics induce polarized Cdc42 activity, which induces MTOC localization through the Par6-protein kinase Czeta complex.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

LinkOut - more resources