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bioRxiv · 10.1101/2024.08.30.610474

Convergent and lineage-specific genomic changes contribute to adaptations in sugar-consuming birds

Abstract

High-sugar diets cause human metabolic diseases, yet several bird lineages convergently adapted to feeding on sugar-rich nectar or fruits. We investigated the underlying molecular mechanisms in hummingbirds, parrots, honeyeaters, and sunbirds by generating nine new genomes and 90 tissue-specific transcriptomes. Comparative screens revealed an excess of repeated selection in both protein-coding and regulatory sequences in sugar-feeding birds, suggesting reuse of genetic elements. Sequence or expression changes in sugar-feeders affect genes involved in blood pressure regulation, lipid, amino acid and carbohydrate metabolism, with experiments showing functional changes in honeyeater hexokinase 3. MLXIPL, a key regulator of sugar and lipid homeostasis, showed convergent sequence and regulatory changes across all sugar-feeding clades; experiments revealed enhanced sugar-induced transcriptional activity of hummingbird MLXIPL, highlighting its adaptive role in high-sugar diets. Summary Figure: Our comparative screens across four independent sugar-feeding bird groups identified both repeated and lineage-specific targets of selection O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=65 SRC="FIGDIR/small/610474v2_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@148f5c8org.highwire.dtl.DTLVardef@1005dbaorg.highwire.dtl.DTLVardef@1097facorg.highwire.dtl.DTLVardef@9d365c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Osipova, E., Ko, M.-C., Petricek, K. M., Yung Wa Sin, S., Brown, T., Winkler, S., PIppel, M., Jarrells, J., Weiche, S., Mosbech, M.-B., Taborsak-Lines, F., Wang, C., Contreras-Lopez, O., Olsen, R.-A., Ewels, P., Mendez Aranda, D., Gaede, A., Sadanandan, K., Weijie Low, G., Monte, A., Ballerstaedt, N., Adreani, N. M., Mentesana, L., von Bayern, A., Rico-Guevara, A., Edwards, S., Altshuler, D., Buttemer, W. A., Frankl-Vilches, C., Kuhl, H., Bakker, A., Gahr, M., Schupp, M., Baldwin, M. W., Hiller, M., Sackton, T. B.. 2024-09-01. Convergent and lineage-specific genomic changes contribute to adaptations in sugar-consuming birds. https://doi.org/10.1101/2024.08.30.610474

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