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Updated: May 30, 2026
11:19
Spatiotemporal Analysis of Cytokinetic Events in Fission Yeast
Published on: February 20, 2017
Spatial control of Cdc42 activation determines cell width in fission yeast
1Rockefeller University, New York, NY 10065, USA. felice.kelly@gmail.com
Molecular Biology of the Cell
|August 19, 2011
Summary
In fission yeast, the proteins Rga4 and Scd1 control cell width by regulating the small GTPase Cdc42. Their distinct localizations create a gradient of activated Cdc42, determining cell dimensions.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- Fission yeast (Schizosaccharomyces pombe) exhibits simple geometry, ideal for studying cellular dimension control.
- Cellular width is maintained consistently throughout the cell cycle.
Purpose of the Study:
- To identify genes controlling fission yeast cell width.
- To investigate the roles of specific proteins in regulating cell dimensions.
Main Methods:
- Genome-wide screen for wider fission yeast mutants.
- Gene deletion analysis.
- Protein localization studies.
- Analysis of small GTPase Cdc42 activity.
Main Results:
- Identified 11 deletion mutants with increased cell width.
- Seven mutants involved genes regulating the small GTPase Cdc42, including Scd1 (GEF) and Rga4 (GAP).
- Rga4 and Scd1 exhibit independent localization (cell sides and tips, respectively) and are crucial for cell width determination.
Conclusions:
- Rga4 and Scd1 establish an activated Cdc42 gradient at the cell tip plasma membrane.
- This gradient dictates the size of the growth zone and normal cell width in fission yeast.
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