bicoid mRNA localises to the Drosophila oocyte anterior by random Dynein-mediated transport and anchoring
bicoid mRNA localises to the Drosophila oocyte anterior from stage 9 of oogenesis onwards to provide a local source for Bicoid protein for embryonic patterning. Live imaging at stage 9 reveals that bicoid mRNA particles undergo rapid Dynein-dependent movements near the oocyte anterior, but with no directional bias. Furthermore, bicoid mRNA localises normally in shot2A2, which abolishes the polarised microtubule organisation. FRAP and photo-conversion experiments demonstrate that the RNA is stably anchored at the anterior, independently of microtubules. Thus, bicoid mRNA is localised by random active transport and anterior anchoring. Super-resolution imaging reveals that bicoid mRNA forms 110-120nm particles with variable RNA content, but constant size. These particles appear to be well-defined structures that package the RNA for transport and anchoring.
Article and author information
European Commission (Seventh Framework Programme (FP7), Marie Curie Intraeuropean felowship, 236621)
- Vítor Trovisco
Biotechnology and Biological Sciences Research Council (BBSRC/EURORNAQ , BB/F010303)
- Daniel St Johnston
Darwin Trust Scholarship
- Katsiaryna Belaya
Wellcome (Strategic Award, 095297)
- George Sirinakis
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Mani Ramaswami, Trinity College Dublin, Ireland
- Received: May 5, 2016
- Accepted: October 25, 2016
- Accepted Manuscript published: October 28, 2016 (version 1)
- Accepted Manuscript updated: October 31, 2016 (version 2)
- Accepted Manuscript updated: November 2, 2016 (version 3)
- Version of Record published: November 28, 2016 (version 4)
© 2016, Trovisco et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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