UMMS Affiliation

Program in Molecular Medicine

Publication Date


Document Type



Biochemistry, Biophysics, and Structural Biology | Ecology and Evolutionary Biology | Genetic Phenomena | Genetics and Genomics | Molecular Biology


Transposons are major genome constituents that can mobilize and trigger mutations, DNA breaks and chromosome rearrangements. Transposon silencing is particularly important in the germline, which is dedicated to transmission of the inherited genome. Piwi-interacting RNAs (piRNAs) guide a host defence system that transcriptionally and post-transcriptionally silences transposons during germline development. While germline control of transposons by the piRNA pathway is conserved, many piRNA pathway genes are evolving rapidly under positive selection, and the piRNA biogenesis machinery shows remarkable phylogenetic diversity. Conservation of core function combined with rapid gene evolution is characteristic of a host-pathogen arms race, suggesting that transposons and the piRNA pathway are engaged in an evolutionary tug of war that is driving divergence of the biogenesis machinery. Recent studies suggest that this process may produce biochemical incompatibilities that contribute to reproductive isolation and species divergence.


adaptive evolution, host–pathogen arms race, pathogen mimicry, piRNA, transposon regulation

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Copyright 2019 The Authors. Published by the Royal Society under the terms of the Creative Commons Attribution License, which permits unrestricted use, provided the original author and source are credited.

DOI of Published Version



Open Biol. 2019 Jan 31;9(1):180181. doi: 10.1098/rsob.180181. Link to article on publisher's site

Journal/Book/Conference Title

Open biology

Related Resources

Link to Article in PubMed

PubMed ID


Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.



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