Divergence in gene expression within and between two closely related flycatcher species
2016 (English)In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, no 9, 2015-2028 p.Article in journal (Refereed) Published
Relatively little is known about the character of gene expression evolution as species diverge. It is for instance unclear if gene expression generally evolves in a clock-like manner (by stabilizing selection or neutral evolution) or if there are frequent episodes of directional selection. To gain insights into the evolutionary divergence of gene expression, we sequenced and compared the transcriptomes of multiple organs from population samples of collared (Ficedula albicollis) and pied flycatchers (F. hypoleuca), two species which diverged less than one million years ago. Ordination analysis separated samples by organ rather than by species. Organs differed in their degrees of expression variance within species and expression divergence between species. Variance was negatively correlated with expression breadth and protein interactivity, suggesting that pleiotropic constraints reduce gene expression variance within species. Variance was correlated with between-species divergence, consistent with a pattern expected from stabilizing selection and neutral evolution. Using an expression PST approach, we identified genes differentially expressed between species and found 16 genes uniquely expressed in one of the species. For one of these, DPP7, uniquely expressed in collared flycatcher, the absence of expression in pied flycatcher could be associated with a ≈ 20 kb deletion including 11 out of 13 exons. This study of a young vertebrate speciation model system expands our knowledge of how gene expression evolves as natural populations become reproductively isolated.
Place, publisher, year, edition, pages
2016. Vol. 25, no 9, 2015-2028 p.
collared flycatcher; Ficedula; gene regulation; pied flycatcher; speciation; transcriptomics
IdentifiersURN: urn:nbn:se:uu:diva-280030DOI: 10.1111/mec.13596ISI: 000377023400010PubMedID: 26928872OAI: oai:DiVA.org:uu-280030DiVA: diva2:909563
FunderSwedish Research Council, 2010-5650 2013-8271EU, European Research Council, AdG 249976Knut and Alice Wallenberg FoundationWellcome trust, WT095908 WT098051