Growing microtubules push the oocyte nucleus to polarize the Drosophila dorsal-ventral axis

Science. 2012 May 25;336(6084):999-1003. doi: 10.1126/science.1219147. Epub 2012 Apr 12.

Abstract

The Drosophila dorsal-ventral (DV) axis is polarized when the oocyte nucleus migrates from the posterior to the anterior margin of the oocyte. Prior work suggested that dynein pulls the nucleus to the anterior side along a polarized microtubule cytoskeleton, but this mechanism has not been tested. By imaging live oocytes, we find that the nucleus migrates with a posterior indentation that correlates with its direction of movement. Furthermore, both nuclear movement and the indentation depend on microtubule polymerization from centrosomes behind the nucleus. Thus, the nucleus is not pulled to the anterior but is pushed by the force exerted by growing microtubules. Nuclear migration and DV axis formation therefore depend on centrosome positioning early in oogenesis and are independent of anterior-posterior axis formation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Patterning
  • Cell Nucleus / physiology*
  • Cell Nucleus / ultrastructure
  • Cell Polarity
  • Centrosome / physiology
  • Drosophila
  • Drosophila Proteins / physiology
  • Dyneins / physiology
  • Microtubule-Organizing Center / physiology
  • Microtubule-Organizing Center / ultrastructure
  • Microtubules / physiology*
  • Microtubules / ultrastructure
  • Movement
  • Mutation
  • Nuclear Envelope / physiology
  • Nuclear Envelope / ultrastructure
  • Oocytes / physiology*
  • Oocytes / ultrastructure
  • Oogenesis*

Substances

  • Drosophila Proteins
  • Dyneins