Dataset Information

Differential activation and inhibition of RhoA by fluid flow induced shear stress in chondrocytes.

ABSTRACT: Physical force environment is a major factor that influences cellular homeostasis and remodelling. It is not well understood, however, as a potential role of force intensities in the induction of cellular mechanotransduction. Using a fluorescence resonance energy transfer-based approach, we asked whether activities of GTPase RhoA in chondrocytes are dependent on intensities of flow-induced shear stress. We hypothesized that RhoA activities can be either elevated or reduced by selecting different levels of shear-stress intensities. The result indicates that C28/I2 chondrocytes have increased RhoA activities in response to high shear stress (10 or 20?dyn/cm(2) ), whereas a decrease in activity was seen with an intermediate shear stress of 5?dyn/cm(2) . No changes were seen under low shear stress (2?dyn/cm(2) ). The observed two-level switch of RhoA activities is closely linked to the shear-stress-induced alterations in actin cytoskeleton and traction forces. In the presence of constitutively active RhoA (RhoA-V14), intermediate shear stress suppressed RhoA activities, while high shear stress failed to activate them. In chondrocytes, expression of various metalloproteinases is, in part, regulated by shear and normal stresses through a network of GTPases. Collectively, the data suggest that intensities of shear stress are critical in differential activation and inhibition of RhoA activities in chondrocytes.

SUBMITTER: Wan Q

PROVIDER: S-EPMC3650118 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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Differential activation and inhibition of RhoA by fluid flow induced shear stress in chondrocytes.

Wan Qiaoqiao Q Kim Seung Joon SJ Yokota Hiroki H Na Sungsoo S

Cell biology international 20130313 6

Physical force environment is a major factor that influences cellular homeostasis and remodelling. It is not well understood, however, as a potential role of force intensities in the induction of cellular mechanotransduction. Using a fluorescence resonance energy transfer-based approach, we asked whether activities of GTPase RhoA in chondrocytes are dependent on intensities of flow-induced shear stress. We hypothesized that RhoA activities can be either elevated or reduced by selecting different ...[more]

PMID: 23408748

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Dataset Information

Differential activation and inhibition of RhoA by fluid flow induced shear stress in chondrocytes.

Publications

Differential activation and inhibition of RhoA by fluid flow induced shear stress in chondrocytes.

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