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Updated: Aug 17, 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

Mutations in the ATP-binding domain affect the subcellular distribution of mitotic centromere-associated kinesin

L Wordeman1, M Wagenbach, T Maney

  • 1Department of Physiology and Biophysics, University of Washington School of Medicine, Seattle, WA 98195, USA.

Cell Biology International
|December 22, 1999
PubMed

Insights

Mitotic centromere-associated kinesin (MCAK) is crucial for chromosome segregation. Its nuclear localization, regulated by NLS and NES sequences, impacts centromere binding and mitotic function.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Genetics

Background:

  • Mitotic centromere-associated kinesin (MCAK) plays a vital role in anaphase chromosome segregation.
  • MCAK exhibits dynamic subcellular localization, shifting between cytoplasm, nucleus, and centromeres during the cell cycle.

Purpose of the Study:

  • To investigate the regulatory mechanisms governing MCAK's subcellular distribution.
  • To determine how MCAK's localization influences its function in chromosome segregation.

Main Methods:

  • Utilized GFP-tagged MCAK deletion constructs to analyze subcellular localization.
  • Introduced amino acid substitutions in the ATP-binding domain to assess effects on nuclear localization and centromere binding.

Main Results:

  • MCAK's nucleocytoplasmic ratio is determined by a balance of nuclear localization sequences (NLS) and a nuclear exclusion sequence (NES) in its amino-terminal region.
  • Modifications within the ATP-binding domain alter MCAK's nuclear import/export, consequently affecting its centromere binding efficiency.

Conclusions:

  • MCAK's dynamic localization is tightly regulated by specific protein domains and sequences.
  • Proper subcellular distribution of MCAK is essential for its function in accurate chromosome segregation during mitosis.

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