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Updated: Jul 16, 2026

Live Cell Imaging of Microtubule Cytoskeleton and Micromechanical Manipulation of the Arabidopsis Shoot Apical Meristem
07:52

Live Cell Imaging of Microtubule Cytoskeleton and Micromechanical Manipulation of the Arabidopsis Shoot Apical Meristem

Published on: May 23, 2020

Arabidopsis MICROTUBULE-ASSOCIATED PROTEIN18 functions in directional cell growth by destabilizing cortical

Xia Wang1, Lei Zhu, Baoquan Liu

  • 1State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing 100094, China.

The Plant Cell
|March 6, 2007
PubMed

Insights

Arabidopsis MAP18 protein destabilizes microtubules, impacting cell growth. Overexpression causes polarity loss, while reduced MAP18 alters microtubule organization and drug sensitivity.

Area of Science:

  • Plant cell biology
  • Molecular plant science
  • Cytoskeletal dynamics

Background:

  • Microtubule-associated proteins (MAPs) are crucial for regulating microtubule functions within cells.
  • Understanding MAPs in plants is key to deciphering cell growth and organization.

Purpose of the Study:

  • To investigate the function of Arabidopsis thaliana MAP18 (AtMAP18) in microtubule regulation and plant cell growth.
  • To determine the effects of AtMAP18 on tubulin polymerization and microtubule organization.

Main Methods:

  • In vitro tubulin polymerization assays to assess AtMAP18's effect on polymerization.
  • Confocal microscopy to observe AtMAP18 localization and cortical microtubule arrays in vivo.
  • Genetic manipulation (overexpression and RNA interference) to study AtMAP18 function.
  • Treatment with microtubule-disrupting drugs to assess microtubule stability.

Main Results:

  • AtMAP18 binds to microtubules and inhibits tubulin polymerization in vitro.
  • AtMAP18 localizes to cortical microtubules in dot-like structures, primarily in expanding cells.
  • Overexpression of AtMAP18 leads to growth defects, loss of polarity, and altered cortical microtubule organization.
  • Downregulation of AtMAP18 via RNA interference also affects microtubule organization.
  • Overexpression increases sensitivity to microtubule-disrupting drugs, while RNAi confers resistance.

Conclusions:

  • AtMAP18 plays a significant role in regulating directional cell growth in Arabidopsis.
  • MAP18 destabilizes microtubules, contributing to the dynamic organization of the cortical microtubule cytoskeleton.
  • These findings provide insights into how MAPs modulate plant cell morphogenesis.

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