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Updated: May 11, 2026
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Spatiotemporal Control of Protein Activity through Optogenetic Allosteric Regulation
Published on: October 4, 2024
Csi1 illuminates the mechanism and function of Rabl configuration
Haitong Hou1, Scott P Kallgren, Songtao Jia
1Department of Biological Sciences, Columbia University, New York, NY, USA.
Nucleus (Austin, Tex.)
|May 15, 2013
Summary
Fission yeast centromeres cluster at the nuclear envelope via Sad1 and Csi1 proteins. This clustering is vital for efficient kinetochore capture by microtubules during cell division.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The nuclear envelope organizes the genome and connects the nucleus to the cytoskeleton via SUN-KASH proteins.
- In fission yeast, centromeres cluster near the nuclear periphery during interphase.
Purpose of the Study:
- To investigate the proteins connecting centromeres to the nuclear envelope.
- To understand the role of centromere clustering in mitosis.
Main Methods:
- Utilized fission yeast as a model organism.
- Investigated the roles of the SUN domain protein Sad1 and the novel protein Csi1.
Main Results:
- Sad1 and Csi1 connect fission yeast centromeres to the inner nuclear membrane.
- Centromere clustering during interphase is essential for efficient kinetochore-microtubule attachment in mitosis.
Conclusions:
- Sad1 and Csi1 mediate centromere-nuclear envelope connections.
- Interphase centromere clustering is a prerequisite for proper mitotic spindle assembly and chromosome segregation.
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