Competition between kinesin-1 and myosin-V defines Drosophila posterior determination
Local accumulation of oskar (osk) mRNA in the Drosophila oocyte determines the posterior pole of the future embryo. Two major cytoskeletal components, microtubules and actin filaments, together with a microtubule motor, kinesin-1, and an actin motor, myosin-V, are essential for osk mRNA posterior localization. In this study, we use Staufen, an RNA-binding protein that colocalizes with osk mRNA, as a proxy for osk mRNA. We demonstrate that posterior localization of osk/Staufen is determined by competition between kinesin-1 and myosin-V. While kinesin-1 removes osk/Staufen from the cortex along microtubules, myosin-V anchors osk/Staufen at the cortex. Myosin-V wins over kinesin-1 at the posterior pole due to low microtubule density at this site, while kinesin-1 wins at anterior and lateral positions because they have high density of cortically-anchored microtubules. As a result, posterior determinants are removed from the anterior and lateral cortex but retained at the posterior pole. Thus, posterior determination of Drosophila oocytes is defined by kinesin-myosin competition, whose outcome is primarily determined by cortical microtubule density.
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
National Institute of General Medical Sciences (GM124029)
- Vladimir I Gelfand
National Institute of General Medical Sciences (GM131752)
- Vladimir I Gelfand
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Yukiko M Yamashita, University of Michigan, United States
- Received: December 5, 2019
- Accepted: February 14, 2020
- Accepted Manuscript published: February 14, 2020 (version 1)
- Version of Record published: April 1, 2020 (version 2)
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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