Biology and pathology of Rho GTPase, PI-3 kinase-Akt, and MAP kinase signaling pathways in chondrocytes
Article first published online: 14 APR 2010
Copyright © 2010 Wiley-Liss, Inc.
Journal of Cellular Biochemistry
Volume 110, Issue 3, pages 573–580, 1 June 2010
How to Cite
Beier, F. and Loeser, R. F. (2010), Biology and pathology of Rho GTPase, PI-3 kinase-Akt, and MAP kinase signaling pathways in chondrocytes. J. Cell. Biochem., 110: 573–580. doi: 10.1002/jcb.22604
- Issue published online: 20 MAY 2010
- Article first published online: 14 APR 2010
- Manuscript Accepted: 4 MAR 2010
- Manuscript Received: 3 MAR 2010
- NIH. Grant Numbers: AG16697, AR49003
- cell signaling;
Chondrocytes provide the framework for the developing skeleton and regulate long-bone growth through the activity of the growth plate. Chondrocytes in the articular cartilage, found at the ends of bones in diarthroidial joints, are responsible for maintenance of the tissue through synthesis and degradation of the extracellular matrix. The processes of growth, differentiation, cell death and matrix remodeling are regulated by a network of cell signaling pathways in response to a variety of extracellular stimuli. These stimuli consist of soluble ligands, including growth factors and cytokines, extracellular matrix proteins, and mechanical factors that act in concert to regulate chondrocyte function through a variety of canonical and non-canonical signaling pathways. Key chondrocyte signaling pathways include, but are not limited to, the p38, JNK and ERK MAP kinases, the PI-3 kinase-Akt pathway, the Jak-STAT pathway, Rho GTPases and Wnt-β-catenin and Smad pathways. Modulation of the activity of any of these pathways has been associated with various pathological states in cartilage. This review focuses on the Rho GTPases, the PI-3 kinase-Akt pathway, and some selected aspects of MAP kinase signaling. Most studies to date have examined these pathways in isolation but it is becoming clear that there is significant cross-talk among the pathways and that the overall effects on chondrocyte function depend on the balance in activity of multiple signaling proteins. J. Cell. Biochem. 110: 573–580, 2010. © 2010 Wiley-Liss, Inc.