Neurons are specialized cell types which send out processes in order to communicate with other cells, which can be immediate neighbors or whose cell bodies are far distant. Neuronal morphology as in all cells is determined in large part through the regulation of the cytoskeleton. One of the key regulators of the actin cytoskeleton is the Rho family of GTPases. The Rho GTPases function as molecular switches to turn on or off downstream biochemical pathways depending on the stimuli. Their activities and their regulation are controlled by many other proteins such as the guanine nucleotide exchange factors and the GTPase-activating proteins. The activities of some of the Rho family members are reported to be antagonistic to one another. In general, Rac and Cdc42 promote neurite outgrowth while RhoA stimulates retraction. The balance of these opposing activities of the different Rho GTPases is crucial for the morphology and function of the neurons.
© 2007 S. Karger AG, Basel
- Rho GTPases
- Actin cytoskeleton
- Guanine nucleotide exchange factor
- GTPase-activating protein
- Guidance cue
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Received: December 18, 2006
Accepted after revision: February 15, 2007
Published online: April 4, 2007
Number of Print Pages : 10
Number of Figures : 2, Number of Tables : 1, Number of References : 82
Vol. 15, No. 5, Year 2006/2007 (Cover Date: August 2007)
Journal Editor: Ip, N.Y. (Hong Kong)
ISSN: 1424–862X (print), 1424–8638 (Online)
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