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Rho GTPases in cell biology


Rho GTPases are molecular switches that control a wide variety of signal transduction pathways in all eukaryotic cells. They are known principally for their pivotal role in regulating the actin cytoskeleton, but their ability to influence cell polarity, microtubule dynamics, membrane transport pathways and transcription factor activity is probably just as significant. Underlying this biological complexity is a simple biochemical idea, namely that by switching on a single GTPase, several distinct signalling pathways can be coordinately activated. With spatial and temporal activation of multiple switches factored in, it is not surprising to find Rho GTPases having such a prominent role in eukaryotic cell biology.

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We are grateful for support from Cancer Research UK and the Medical Research Council. S.E.-M. is supported by an EMBO long-term fellowship.

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Correspondence to Alan Hall.

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Further reading

Figure 1: The Rho GTPase cycle.
Figure 2: Morphogenesis.
Figure 3: Movement.
Figure 4: Behaviour.


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