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Updated: Aug 3, 2026
12:19
Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
Rac1 is required for cell proliferation and G2/M progression
K A Moore1, R Sethi, A M Doanes
1Cardiology Branch, National Heart, Lung and Blood Institute, Bethesda, MD 20892-1650, USA.
The Biochemical Journal
|August 15, 1997
Summary
Dominant negative rac1 (N17rac1) expression halts cell proliferation by arresting cells in G2/M. This study demonstrates rac1
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Rac1 is a small GTP-binding protein involved in various cellular processes.
- The precise role of rac1 in cell cycle progression, particularly in mammalian cells, remains incompletely understood.
Purpose of the Study:
- To investigate the role of rac1 in mammalian cell proliferation.
- To determine the effect of dominant-negative rac1 expression on cell cycle progression.
Main Methods:
- Adenoviral-mediated gene transfer was used to express a dominant-negative form of rac1 (N17rac1) in Rat 2 fibroblasts.
- Expression levels were correlated with the multiplicity of infection.
- Cell-cycle analysis was performed to assess cell cycle distribution.
Main Results:
- Expression of N17rac1 resulted in cytostatic growth arrest.
- Cells expressing N17rac1 accumulated in the G2/M phase of the cell cycle.
- The level of N17rac1 expression was proportional to the multiplicity of infection.
Conclusions:
- Rac1 is essential for mammalian cell proliferation.
- This study provides the first evidence in mammalian cells linking small GTP-binding proteins to the G2/M cell cycle transition.
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