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Updated: Aug 29, 2026

Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins
05:35

Immunofluorescence Analysis of Endogenous and Exogenous Centromere-kinetochore Proteins

Published on: March 3, 2016

Depletion of centromeric MCAK leads to chromosome congression and segregation defects due to improper kinetochore

Susan L Kline-Smith1, Alexey Khodjakov, Polla Hergert

  • 1Departments of Anatomy and Cell Biology, Indiana University Medical Sciences Program, Bloomington, Indiana 47405, USA.

Molecular Biology of the Cell
|December 31, 2003
PubMed

Insights

Kinesin Inhibitor (Kin I) depletion causes chromosome missegregation by disrupting kinetochore-microtubule attachments. This study reveals MCAK

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Kinetochore microtubules are crucial for chromosome segregation during mitosis.
  • Kinesin Inhibitors (Kin Is) are implicated in regulating chromosome positioning.
  • MCAK is a key Kin I involved in microtubule dynamics.

Purpose of the Study:

  • To characterize the localization and function of centromere-bound MCAK during mitosis.
  • To investigate the consequences of MCAK disruption on chromosome congression and segregation.
  • To determine MCAK's role in kinetochore-microtubule attachments.

Main Methods:

  • Immunofluorescence localization of centromere-bound MCAK.
  • Injection of a dominant-negative protein to disrupt MCAK function.
  • Analysis of chromosome congression, alignment, and segregation.
  • Assessment of kinetochore-microtubule attachment fidelity.

Main Results:

  • MCAK localization shifts from inner kinetochores to centromeres during mitosis.
  • MCAK accumulates at leading kinetochores during chromosome congression.
  • MCAK depletion causes delayed congression, alignment defects, and chromosome missegregation.
  • Disruption of MCAK leads to merotelic and syntelic kinetochore-microtubule attachments.

Conclusions:

  • MCAK plays a critical role in preventing and correcting improper kinetochore-microtubule attachments.
  • MCAK's primary function is not chromosome movement but ensuring attachment fidelity.
  • Kin Is are essential for accurate chromosome segregation through proper microtubule regulation.

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