Bacterial contribution to genesis of the novel germ line determinant oskar
Abstract
New cellular functions and developmental processes can evolve by modifying existing genes or creating novel genes. Novel genes can arise not only via duplication or mutation but also by acquiring foreign DNA, also called horizontal gene transfer (HGT). Here we show that HGT likely contributed to the creation of a novel gene indispensable for reproduction in some insects. Long considered a novel gene with unknown origin, oskar has evolved to fulfil a crucial role in insect germ cell formation. Our analysis of over 100 insect Oskar sequences suggests that Oskar arose de novo via fusion of eukaryotic and prokaryotic sequences. This work shows that highly unusual gene origin processes can give rise to novel genes that can facilitate evolution of novel developmental mechanisms.
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Article and author information
Author details
Funding
Harvard University
- Leo Blondel
Harvard University
- Cassandra G Extavour
Harvard University
- Tamsin E M Jones
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Antonis Rokas, Vanderbilt University, United States
Publication history
- Received: January 29, 2019
- Accepted: February 23, 2020
- Accepted Manuscript published: February 24, 2020 (version 1)
- Version of Record published: May 26, 2020 (version 2)
Copyright
© 2020, Blondel 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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