Standard Article

Microtubule Organization in Dictyostelium

  1. Ralph Gräf

Published Online: 15 DEC 2009

DOI: 10.1002/9780470015902.a0021852

eLS

eLS

How to Cite

Gräf, R. 2009. Microtubule Organization in Dictyostelium. eLS. .

Author Information

  1. University of Potsdam, Institute for Biochemistry and Biology, Potsadm-Golm, Germany

Publication History

  1. Published Online: 15 DEC 2009

This is not the most recent version of the article. View current version (16 FEB 2015)

Abstract

Dictyostelium amoebae contain a radial array of microtubules emanating from a single microtubule-organizing centre called centrosome that is bound to the cytosolic face of the nucleus. Their centrosome contains no centrioles but consists of a layered core surrounded by a corona harbouring microtubule nucleation centres. It duplicates in prophase of a closed mitosis and organizes a central spindle that drives centrosome separation and chromosome segregation. Though Dictyostelium microtubules are quite dynamic during mitosis, their length appears to be very stable during interphase. Microtubules are associated with a couple of conserved proteins (microtubule-associated protein, MAPs), which are involved in centrosome biogenesis and the crosstalk of microtubule tips with the actin cell cortex. The latter becomes evident in cytokinesis, when centrosomes with their attached microtubules participate in the positioning of cleavage furrows.

Key concepts:

  • Dictyostelium amoebae contain a nucleus-associated centrosome that serves as the only microtubule-organizing centre.

  • The Dictyostelium centrosome contains no centrioles, but consists of a three-layered core structure surrounded by a microtubule-nucleating corona.

  • If compared to the three major plaques of the yeast spindle pole body, the entire core structure of the Dictyostelium centrosome appears equivalent to the central plaque, whereas the corona plays a similar role as the inner and outer plaques.

  • Dictyostelium centrosomes duplicate at the onset of mitosis.

  • Dictyostelium amoebae show a closed-type of mitosis with a persisting nuclear envelope.

  • Dictyostelium microtubules are quite dynamic during mitosis but show only little growth and shrinkage during interphase.

  • Microtubule plus ends influence actin dynamics at the cell cortex.

  • Dictyostelium amoebae are a useful model to study the role of the centrosome and microtubules in cell dynamics and disease.

Keywords:

  • Dictyostelium;
  • centrosome;
  • MAP;
  • microtubules;
  • mitosis