Adaptive Evolution Leads to Cross-Species Incompatibility in the piRNA Transposon Silencing Machinery
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UMass Chan Affiliations
Department of Biochemistry and Molecular PharmacologyProgram in Bioinformatics and Integrative Biology
Program in Molecular Medicine
Document Type
Journal ArticlePublication Date
2017-10-09Keywords
adaptive evolutionchromatin
piRNA
reproductive isolation
transposon silencing
Biochemistry, Biophysics, and Structural Biology
Bioinformatics
Computational Biology
Developmental Biology
Ecology and Evolutionary BiologyIntegrative BiologySystems Biology
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Reproductive isolation defines species divergence and is linked to adaptive evolution of hybrid incompatibility genes. Hybrids between Drosophila melanogaster and Drosophila simulans are sterile, and phenocopy mutations in the PIWI interacting RNA (piRNA) pathway, which silences transposons and shows pervasive adaptive evolution, and Drosophila rhino and deadlock encode rapidly evolving components of a complex that binds to piRNA clusters. We show that Rhino and Deadlock interact and co-localize in simulans and melanogaster, but simulans Rhino does not bind melanogaster Deadlock, due to substitutions in the rapidly evolving Shadow domain. Significantly, a chimera expressing the simulans Shadow domain in a melanogaster Rhino backbone fails to support piRNA production, disrupts binding to piRNA clusters, and leads to ectopic localization to bulk heterochromatin. Fusing melanogaster Deadlock to simulans Rhino, by contrast, restores localization to clusters. Deadlock binding thus directs Rhino to piRNA clusters, and Rhino-Deadlock co-evolution has produced cross-species incompatibilities, which may contribute to reproductive isolation.Source
Dev Cell. 2017 Oct 9;43(1):60-70.e5. doi: 10.1016/j.devcel.2017.08.012. Epub 2017 Sep 14. Link to article on publisher's siteDOI
10.1016/j.devcel.2017.08.012Permanent Link to this Item
http://hdl.handle.net/20.500.14038/25830PubMed ID
28919205Related Resources
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