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bioRxiv · 10.64898/2026.05.21.726714

Evolutionary rate correlations reveal long-term co-evolutionary interactions in Drosophila melanogaster

Dagilis, A. J.·DiAngelis, B.·Lee, S.·Matute, D. R.
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Abstract

Co-evolution between genes can occur for a variety of reasons, including co-expression of genes, epistatic interactions between them, physical interactions of gene products and many others. Co-evolutionary partners of a gene are therefore of great interest in identifying potential factors that contribute to any phenotype of interest. State-of-the-art approaches to detect these interactions use correlations of evolutionary rates across a broader phylogeny, and so by necessity identify interactions only among genes that are present across long evolutionary time periods. This makes the methods unwieldy when interest lies in a single focal organism in which the genes of interest may have evolved in the recent evolutionary past. Here, we present a new approach to calculating evolutionary rate correlations which focuses on extracting maximum coverage for a single focal species, while retaining signals of co-evolution across large clades. We show how this approach is able to identify potential interactions even in highly studied species and highly studied genes, with a focus on the D. melanogaster sex-determiner, Sxl, using data from 72 species of Dipterans.

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Dagilis, A. J., DiAngelis, B., Lee, S., Matute, D. R.. 2026-05-23. Evolutionary rate correlations reveal long-term co-evolutionary interactions in Drosophila melanogaster. https://doi.org/10.64898/2026.05.21.726714

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