First published online August 25, 2006
Development 133, 1801e (2006)
© The Company of Biologists Limited
CDC-42 takes a cell polarity PARtner
The establishment of polarity is an important developmental event. In
C. elegans, the segregation of different PAR proteins into anterior
and posterior cortical domains establishes anteroposterior polarity in
one-cell embryos. PAR protein segregation is coupled to rearrangements of the
embryo's acto-myosin cytoskeleton. Schonegg and Hyman now report that the Rho
family GTPases CDC-42 and RHO-1 coordinate acto-myosin contractility and PAR
protein localization during polarity establishment in these embryos (see
p. 3507). Using live
imaging of GFP-tagged PAR proteins and RNAi depletion of rho-1 and
cdc-42, the researchers show that RHO-1 activity helps to localize
CDC-42 to the anterior of the embryo by participating in the early
organization of the myosin cytoskeleton. CDC-42 then stabilizes the actomyosin
network and localizes PAR-6 to the anterior cortex. Although these results
differ from other data that indicate that CDC-42 helps to maintain but not
establish polarity, they provide important new insights into how RHO-1 and
CDC-42 might interact during developmental cell polarization events.
Related articles in Development:
- CDC-42 and RHO-1 coordinate acto-myosin contractility and PAR protein localization during polarity establishment in C. elegans embryos
- Stephanie Schonegg and Anthony A. Hyman
Development 2006 133: 3507-3516.
[Abstract]
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