The antagonistic roles of PDGF and integrin αvβ3 in regulating ROS production at focal adhesions

Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Biomaterials (Impact Factor: 8.31). 02/2013; 34(15). DOI: 10.1016/j.biomaterials.2013.01.092
Source: PubMed

ABSTRACT Reactive oxygen species (ROS) have been shown to play crucial roles in regulating various cellular functions, e.g. focal adhesion (FA) dynamics and cell migration upon growth factor stimulation. However, it is not clear how ROS are regulated at subcellular FA sites to impact cell migration. We have developed a biosensor capable of monitoring ROS production at FA sites in live cells with high sensitivity and specificity, utilizing fluorescence resonance energy transfer (FRET). The results revealed that platelet derived growth factor (PDGF) can induce ROS production at FA sites, which is mediated by Rac1 activation. In contrast, integrins, specifically integrin αvβ3, inhibits this local ROS production. The RhoA activity can mediate this inhibitory role of integrins in regulating ROS production. Therefore, PDGF and integrin αvβ3 coordinate to have an antagonistic effect in the ROS production at FA sites to regulate cell adhesion and migration.

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