Adaptive Evolution Leads to Cross-Species Incompatibility in the piRNA Transposon Silencing Machinery
UMass Chan AffiliationsDepartment of Biochemistry and Molecular Pharmacology
Program in Bioinformatics and Integrative Biology
Program in Molecular Medicine
Document TypeJournal Article
Biochemistry, Biophysics, and Structural Biology
Ecology and Evolutionary Biology
MetadataShow full item record
AbstractReproductive 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.
SourceDev 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 site
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/25830
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