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Updated: Dec 14, 2025
05:35
Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
Published on: March 3, 2016
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The Structural Basis for Kinetochore Stabilization by Cnn1/CENP-T.
Stephen M Hinshaw1, Stephen C Harrison1
1Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, USA.
Current Biology : CB
|July 18, 2020
Summary
The Ctf19 complex (Ctf19c) is crucial for chromosome segregation. New research reveals how Ctf19c components assemble at the kinetochore, uncovering feedback regulation and conserved mechanisms in yeast and vertebrates.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- Chromosome segregation relies on kinetochore-microtubule attachments.
- The Ctf19 complex (Ctf19c) forms the centromeric base of the budding yeast kinetochore.
- Previous studies showed Ctf19c assembly hierarchy in vitro, but not in vivo.
Purpose of the Study:
- To elucidate the assembly mechanism of the Ctf19 complex at the centromere.
- To investigate the recruitment of the Ctf3 complex (Ctf3c) and Cnn1-Wip1 to the kinetochore.
- To uncover feedback regulation in Ctf19c assembly and conserved kinetochore organization.
Main Methods:
- High-resolution structural analysis of Ctf3c bound to Cnn1-Wip1.
- Live-cell imaging experiments to observe Ctf3c and Cnn1-Wip1 recruitment.
- Biochemical purification and analysis of protein complexes.
Main Results:
- A high-resolution structure of the Ctf3c-Cnn1-Wip1 complex was determined.
- Live-cell imaging revealed the mechanism for Ctf3c and Cnn1-Wip1 kinetochore recruitment.
- The findings suggest a feedback regulation of Ctf19c assembly.
Conclusions:
- The study provides a mechanistic understanding of Ctf19c assembly at the centromere.
- The discovered recruitment mechanism highlights feedback regulation in kinetochore assembly.
- Unanticipated similarities in kinetochore organization between yeast and vertebrates were identified.
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