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Kif18B interacts with EB1 and controls astral microtubule length during mitosis

Jane R Stout1, Amber L Yount, James A Powers

  • 1Medical Sciences Program, Indiana University, Bloomington, IN 47405, USA.

Molecular Biology of the Cell
|July 9, 2011
PubMed

Insights

Human kinesin-8 Kif18B regulates astral microtubule (MT) organization during mitosis. It interacts with EB1 to control MT length, impacting spindle assembly.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Microtubule (MT) dynamics are crucial for cell division, particularly spindle assembly.
  • Kinesin-8 motors regulate MT dynamics, acting as depolymerases or capping proteins at MT plus ends.

Purpose of the Study:

  • To investigate the role of human kinesin-8 Kif18B in mitotic astral MT organization.
  • To identify proteins interacting with Kif18B and elucidate its mechanism of action.

Main Methods:

  • Kif18B knockdown experiments to observe effects on MTs and spindle.
  • Yeast two-hybrid screening to identify interacting proteins.
  • In vitro binding assays and cell-based overexpression studies.

Main Results:

  • Kif18B knockdown led to increased MT number and length, causing spindle defects.
  • Kif18B directly interacts with the MT plus-end-binding protein EB1.
  • EB1 is necessary for Kif18B's proper localization to MT plus ends.

Conclusions:

  • Kif18B is a novel MT plus-tip-tracking protein that regulates astral MT length during mitosis.
  • The interaction between Kif18B and EB1 is critical for Kif18B's function and localization.
  • Kif18B, in conjunction with EB1, plays a key role in controlling MT dynamics for proper spindle organization.

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