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- Gaulton, Kyle J, et al.
(författare)
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Genetic fine mapping and genomic annotation defines causal mechanisms at type 2 diabetes susceptibility loci.
- 2015
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:12, s. 1415-1415
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Tidskriftsartikel (refereegranskat)abstract
- We performed fine mapping of 39 established type 2 diabetes (T2D) loci in 27,206 cases and 57,574 controls of European ancestry. We identified 49 distinct association signals at these loci, including five mapping in or near KCNQ1. 'Credible sets' of the variants most likely to drive each distinct signal mapped predominantly to noncoding sequence, implying that association with T2D is mediated through gene regulation. Credible set variants were enriched for overlap with FOXA2 chromatin immunoprecipitation binding sites in human islet and liver cells, including at MTNR1B, where fine mapping implicated rs10830963 as driving T2D association. We confirmed that the T2D risk allele for this SNP increases FOXA2-bound enhancer activity in islet- and liver-derived cells. We observed allele-specific differences in NEUROD1 binding in islet-derived cells, consistent with evidence that the T2D risk allele increases islet MTNR1B expression. Our study demonstrates how integration of genetic and genomic information can define molecular mechanisms through which variants underlying association signals exert their effects on disease.
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| 2. |
- Shefferson, Richard P., et al.
(författare)
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Drivers of vegetative dormancy across herbaceous perennial plant species
- 2018
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Ingår i: Ecology Letters. - : WILEY. - 1461-023X .- 1461-0248. ; 21:5, s. 724-733
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Tidskriftsartikel (refereegranskat)abstract
- Vegetative dormancy, that is the temporary absence of aboveground growth for 1year, is paradoxical, because plants cannot photosynthesise or flower during dormant periods. We test ecological and evolutionary hypotheses for its widespread persistence. We show that dormancy has evolved numerous times. Most species displaying dormancy exhibit life-history costs of sprouting, and of dormancy. Short-lived and mycoheterotrophic species have higher proportions of dormant plants than long-lived species and species with other nutritional modes. Foliage loss is associated with higher future dormancy levels, suggesting that carbon limitation promotes dormancy. Maximum dormancy duration is shorter under higher precipitation and at higher latitudes, the latter suggesting an important role for competition or herbivory. Study length affects estimates of some demographic parameters. Our results identify life historical and environmental drivers of dormancy. We also highlight the evolutionary importance of the little understood costs of sprouting and growth, latitudinal stress gradients and mixed nutritional modes.
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| 3. |
- Stutz, Rebecca S., et al.
(författare)
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Cohesiveness reduces foraging efficiency in a social herbivore
- 2018
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Ingår i: Animal Behaviour. - : Elsevier BV. - 0003-3472 .- 1095-8282. ; 135, s. 57-68
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Tidskriftsartikel (refereegranskat)abstract
- For social foragers, movement as a group could increase foraging efficiency through collective discovery of high-quality food sources. This would require an efficient mechanism for transferring information about food quality between individuals. Conversely, the constraints of foraging as a cohesive group could decrease efficiency; grouping may persist to serve other functions such as protection from predators. To test what drives cohesion in herbivores, we manipulated patch shape and within-patch pattern of food quality and quantified the effects on group level diet selection by a social herbivore, the fallow deer, Dama dama. We arranged feeders containing fodder in lines or blocks, and manipulated the pattern of food quality within patches by adding tannin, a plant secondary compound that decreases palatability. We quantified the relative consumption of low- and high-tannin food to compare diet selectivity at the group level between patch treatments. If group foraging evolved to increase foraging efficiency, altering the spatial arrangement of food should not affect diet selectivity because information about food location and quality is shared. We found, however, that the herd expressed different levels of selectivity between both patch shapes and food quality patterns. Deer selected better diets in blocks than lines. In lines, the herd selected better diets when quality varied between alternate feeders rather than between the two halves of the patch, suggesting a reliance on personal rather than group information. Deer consumed the most at patch centres in all treatments except in blocks with high-tannin centres, but diet selection was poorer in the latter compared to blocks with low-tannin centres. Aggregation at the centre of patches appears to have restricted exploitation of the best food. Predation pressure and/or resource variability may have favoured the evolution of a foraging strategy that prioritizes social cohesion over effective diet selection.
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