The role of the glycocalyx in reorganization of the actin cytoskeleton under fluid shear stress: A "bumper-car" model

Mia M. Thi, John M. Tarbell, Sheldon Weinbaum, David C. Spray

Research output: Contribution to journalArticle

214 Scopus citations

Abstract

We propose a conceptual model for the cytoskeletal organization of endothelial cells (ECs) based on a major dichotomy in structure and function at basal and apical aspects of the cells. Intracellular distributions of filamentous act in (F-actin), vinculin, paxillin, ZO-1, and Cx43 were analyzed from confocal micrographs of rat fat-pad ECs after 5 h of shear stress. With intact glycocalyx, there was severe disruption of the dense peripheral actin bands (DPABs) and migration of vinculin to cell borders under a uniform shear stress (10.5 dyne/cm2; 1 dyne = 10 μN). This behavior was augmented in corner flow regions of the flow chamber where high shear stress gradients were present. In striking contrast, no such reorganization was observed if the glycocalyx was compromised. These results are explained in terms of a "bumper-car" model, in which the actin cortical web and DPAB are only loosely connected to basal attachment sites, allowing for two distinct cellular signaling pathways in response to fluid shear stress, one transmitted by glycocalyx core proteins as a torque that acts on the actin cortical web (ACW) and DPAB, and the other emanating from focal adhesions and stress fibers at the basal and apical membranes of the cell.

Original languageEnglish (US)
Pages (from-to)16483-16488
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume101
Issue number47
DOIs
StatePublished - Nov 23 2004

Keywords

  • Actin cortical web
  • Dense peripheral actin band
  • Mechanotransduction

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'The role of the glycocalyx in reorganization of the actin cytoskeleton under fluid shear stress: A "bumper-car" model'. Together they form a unique fingerprint.

Cite this