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RhoA is required for cortical retraction and rigidity during mitotic cell rounding
Amy Shaub Maddox1, Keith Burridge
1Department of Cell and Developmental Biology and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA. akshaub@med.unc.edu
The Journal of Cell Biology
|January 23, 2003
Summary
Mitotic cell rounding, a key shape change during cell division, is driven by RhoA signaling. This pathway increases cortical rigidity and actin cytoskeleton rearrangements, essential for cell shape transformation.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Mitotic cell rounding involves actin cytoskeleton rearrangement, de-adhesion, and increased cortical rigidity.
- The precise molecular mechanisms driving mitotic cell rounding remain largely undefined.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying mitotic cell rounding.
- To investigate the role of RhoA signaling in regulating cell shape changes during mitosis.
Main Methods:
- Investigated the role of RhoA and Rho-kinase in mitotic cell rounding.
- Assessed changes in cortical rigidity and actin cytoskeleton.
- Measured RhoA activity and the activity of its inhibitor, p190RhoGAP.
Main Results:
- RhoA is essential for cortical retraction and increased cortical rigidity during mitosis.
- Rho-kinase mediates RhoA's effects on mitotic cell rounding.
- Elevated RhoA activity and decreased p190RhoGAP activity correlate with mitotic entry.
Conclusions:
- Mitotic cell rounding is regulated by a RhoA-dependent pathway.
- Increased RhoA activity promotes actin cytoskeleton rearrangements, enhancing cortical rigidity for cell rounding.
- RhoA signaling is a critical regulator of cell shape changes during mitosis.
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