Genomic signatures of local adaptation to the degree of environmental predictability in rotifers

Franch-Gras, Lluis; Hahn, Christoph; García-Roger, Eduardo M.; Carmona, María José; Serra, Manuel; Gómez, Africa

Abstract

Environmental fuctuations are ubiquitous and thus essential for the study of adaptation. Despite
this, genome evolution in response to environmental fuctuations —and more specifcally to the
degree of environmental predictability– is still unknown. Saline lakes in the Mediterranean region
are remarkably diverse in their ecological conditions, which can lead to divergent local adaptation
patterns in the inhabiting aquatic organisms. The facultatively sexual rotifer Brachionus plicatilis shows
diverging local adaptation in its life-history traits in relation to estimated environmental predictability
in its habitats. Here, we used an integrative approach —combining environmental, phenotypic and
genomic data for the same populations– to understand the genomic basis of this diverging adaptation.
Firstly, a novel draft genome for B. plicatilis was assembled. Then, genome-wide polymorphisms were
studied using genotyping by sequencing on 270 clones from nine populations in eastern Spain. As a
result, 4,543 high-quality SNPs were identifed and genotyped. More than 90 SNPs were found to
be putatively under selection with signatures of diversifying and balancing selection. Over 140 SNPs
were correlated with environmental or phenotypic variables revealing signatures of local adaptation,
including environmental predictability. Putative functions were associated to most of these SNPs, since
they were located within annotated genes. Our results reveal associations between genomic variation
and the degree of environmental predictability, providing genomic evidence of adaptation to local
conditions in natural rotifer populations.

Citation

Franch-Gras, L., Hahn, C., García-Roger, E. M., Carmona, M. J., Serra, M., & Gómez, A. (2018). Genomic signatures of local adaptation to the degree of environmental predictability in rotifers. Scientific reports, 8(1), Article 16051. https://doi.org/10.1038/s41598-018-34188-y

• Journal Article Type: Article
• Acceptance Date: Sep 27, 2018
• Online Publication Date: Oct 30, 2018
• Publication Date: Dec 1, 2018
• Deposit Date: Oct 31, 2018
• Publicly Available Date: Nov 1, 2018
• Journal: Scientific Reports
• Print ISSN: 2045-2322
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 1
• Article Number: 16051
• DOI: https://doi.org/10.1038/s41598-018-34188-y
• Keywords: Multidisciplinary
• Public URL: https://hull-repository.worktribe.com/output/1138730
• Publisher URL: https://www.nature.com/articles/s41598-018-34188-y.pdf
• Contract Date: Nov 1, 2018