Article

Cell cycle regulation of Rho signaling pathways.

Inserm U749, Institut Gustave Roussy, Villejuif, France.
Cell cycle (Georgetown, Tex.) (impact factor: 5.36). 08/2012; 11(16):3003-10. DOI:10.4161/cc.21088
Source: PubMed

ABSTRACT The dynamics of the actin cytoskeleton and its regulation by Rho GTPases are essential to maintain cell shape, to allow cell motility and are also critical during cell cycle progression and mitosis. Rho GTPases and their effectors are involved in cell rounding at mitosis onset, in chromosomes alignment and are required for contraction of the actomyosin ring that separates daughter cells at the end of mitosis. Recent studies have revealed how a number of nucleotide exchange factors and GTPase-activating proteins regulate the activity of Rho GTPases during these processes. This review will focus on how the cell cycle machinery, in turn, regulates expression of proteins in the Rho signaling pathways through transcriptional activation, ubiquitylation and proteasomal degradation and modulates their activity through phosphorylation by mitotic kinases.

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Keywords

actin cytoskeleton
 
actomyosin ring
 
cell cycle machinery
 
chromosomes alignment
 
critical
 
mitosis
 
mitosis onset
 
mitotic kinases
 
nucleotide exchange factors
 
phosphorylation
 
proteasomal degradation
 
Rho GTPases
 
Rho signaling pathways
 
separates daughter cells
 
transcriptional activation