Showing papers by "Tanja Slotte published in 2017"
TL;DR: It is suggested that most common cis-regulatory variation in C. grandiflora is under weak purifying selection, and that gene-specific functional constraints are more important for the maintenance of cis-Regulatory variation than genome-scale variation in the intensity of selection.
Abstract: Understanding the causes of cis-regulatory variation is a long-standing aim in evolutionary biology. Although cis-regulatory variation has long been considered important for adaptation, we still ha ...
55 citations
TL;DR: The view that epigenetic silencing of TEs results in a trade-off between preventing TE proliferation and interference with nearby gene regulation is supported, and it is suggested that in the centromeric and pericentromeric regions, the negative aspects of epigenetic TE silencing are missing.
Abstract: To avoid negative effects of transposable element (TE) proliferation, plants epigenetically silence TEs using a number of mechanisms, including RNA-directed DNA methylation. These epigenetic modifi ...
21 citations
TL;DR: The results demonstrate that intermediate levels of outcrossing may allow efficient selection against harmful alleles whereas demographic effects can be important for relaxed purifying selection in highly selfing populations, and suggest that mixed-mating populations can avoid the negative evolutionary consequences of high self-fertilization rates.
Abstract: Plant mating systems have profound effects on levels and structuring of genetic variation, and can affect the impact of natural selection. While theory predicts that intermediate outcrossing rates may allow plants to prevent accumulation of deleterious alleles, few studies have empirically addressed this using genomic data. Here, we study the effect of mating system on purifying selection by conducting population genomic analyses on whole-genome resequencing data from 38 European individuals of the arctic-alpine crucifer Arabis alpina. We find that outcrossing and mixed-mating populations maintain genetic diversity at similar levels, whereas highly self-fertilizing Scandinavian A. alpina show a strong reduction in genetic diversity, most likely as a result of a postglacial colonization bottleneck. We further find evidence for accumulation of genetic load in highly self-fertilizing populations, whereas the genome-wide impact of purifying selection does not differ greatly between mixed-mating and outcrossing populations. Our results demonstrate that intermediate levels of outcrossing allow efficient selection against harmful alleles whereas demographic effects can be important for relaxed purifying selection in highly selfing populations. Thus, both mating system and demography shape the impact of purifying selection on genomic variation in A. alpina. These results are important for an improved understanding of the evolutionary consequences of mating system variation and the maintenance of mixed-mating strategies.
12 citations