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.
- Leo Blondel
- Cassandra G Extavour
- 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.
- Antonis Rokas, Vanderbilt University, United States
© 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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