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Updated: Jun 6, 2025
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
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Force transmission through the inner kinetochore is enhanced by centromeric DNA sequences
Elise Miedlar1, Grace E Hamilton1, Samuel R Witus1
1Department of Biochemistry, University of Washington, Seattle, United States.
Biorxiv : the Preprint Server for Biology
|November 28, 2024
Summary
Centromeric DNA sequences strengthen linkages within the inner kinetochore, enhancing force transmission from microtubules to chromosomes. This highlights the critical role of DNA in chromosome mechanics.
Area of Science:
- Cell Biology
- Molecular Biology
- Biophysics
Background:
- The inner kinetochore is crucial for transmitting forces between microtubules and chromosomes during cell division.
- Previous work identified two force transmission pathways: Mif2 and the Okp1/Ame1 (OA) complex.
Purpose of the Study:
- To investigate the role of centromeric DNA sequences in kinetochore function.
- To determine how centromeric DNA affects force transmission through the OA complex.
Main Methods:
- Reconstitution of a minimal functional kinetochore using recombinant Saccharomyces cerevisiae proteins.
- Utilized a chimeric DNA sequence containing budding yeast point centromere elements.
- Assessed force transmission in Cse4-containing nucleosomes with and without centromeric DNA.
Main Results:
- Centromeric DNA sequences significantly strengthen OA-mediated linkages in Cse4-containing nucleosomes.
- The presence of centromeric DNA enhances the stability of the OA complex interaction.
- This indicates a direct role for DNA in modulating inner kinetochore mechanics.
Conclusions:
- Centromeric DNA sequences are essential for robust force transmission to chromosomes.
- The OA complex, in conjunction with centromeric DNA, forms a critical linkage for chromosome segregation.
- This finding advances our understanding of the molecular mechanisms underlying chromosome segregation.
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