Search results for "42"
showing 10 items of 3911 documents
sPlotOpen – An environmentally balanced, open‐access, global dataset of vegetation plots
2021
Datos disponibles en https://github.com/fmsabatini/sPlotOpen_Code
The roles of whole-genome and small-scale duplications in the functional specialization of Saccharomyces cerevisiae genes
2013
Researchers have long been enthralled with the idea that gene duplication can generate novel functions, crediting this process with great evolutionary importance. Empirical data shows that whole-genome duplications (WGDs) are more likely to be retained than small-scale duplications (SSDs), though their relative contribution to the functional fate of duplicates remains unexplored. Using the map of genetic interactions and the re-sequencing of 27 Saccharomyces cerevisiae genomes evolving for 2,200 generations we show that SSD-duplicates lead to neo-functionalization while WGD-duplicates partition ancestral functions. This conclusion is supported by: (a) SSD-duplicates establish more genetic i…
Selection for Robustness in Mutagenized RNA Viruses
2007
Mutational robustness is defined as the constancy of a phenotype in the face of deleterious mutations. Whether robustness can be directly favored by natural selection remains controversial. Theory and in silico experiments predict that, at high mutation rates, slow-replicating genotypes can potentially outcompete faster counterparts if they benefit from a higher robustness. Here, we experimentally validate this hypothesis, dubbed the ‘‘survival of the flattest,’’ using two populations of the vesicular stomatitis RNA virus. Characterization of fitness distributions and genetic variability indicated that one population showed a higher replication rate, whereas the other was more robust to mut…
De novo genome assembly of the land snail Candidula unifasciata (Mollusca: Gastropoda)
2021
Abstract Among all molluscs, land snails are a scientifically and economically interesting group comprising edible species, alien species and agricultural pests. Yet, despite their high diversity, the number of genome drafts publicly available is still scarce. Here, we present the draft genome assembly of the land snail Candidula unifasciata, a widely distributed species along central Europe, belonging to the Geomitridae family, a highly diversified taxon in the Western-Palearctic region. We performed whole genome sequencing, assembly and annotation of an adult specimen based on PacBio and Oxford Nanopore long read sequences as well as Illumina data. A genome draft of about 1.29 Gb was gene…
EST based phylogenomics of Syndermata questions monophyly of Eurotatoria
2008
Abstract Background The metazoan taxon Syndermata comprising Rotifera (in the classical sense of Monogononta+Bdelloidea+Seisonidea) and Acanthocephala has raised several hypotheses connected to the phylogeny of these animal groups and the included subtaxa. While the monophyletic origin of Syndermata and Acanthocephala is well established based on morphological and molecular data, the phylogenetic position of Syndermata within Spiralia, the monophyletic origin of Monogononta, Bdelloidea, and Seisonidea and the acanthocephalan sister group are still a matter of debate. The comparison of the alternative hypotheses suggests that testing the phylogenetic validity of Eurotatoria (Monogononta+Bdel…
Multiple paths to cold tolerance: the role of environmental cues, morphological traits and the circadian clock gene vrille
2021
AbstractBackgroundTracing the association between insect cold tolerance and latitudinally and locally varying environmental conditions, as well as key morphological traits and molecular mechanisms, is essential for understanding the processes involved in adaptation. We explored these issues in two closely-related species, Drosophila montana and Drosophila flavomontana, originating from diverse climatic locations across several latitudes on the coastal and mountainous regions of North America. We also investigated the association between sequence variation in one of the key circadian clock genes, vrille, and cold tolerance in both species. Finally, we studied the impact of vrille on fly cold…
Scientific Opinion on application EFSA‐GMO‐BE‐2013‐117 for authorisation of genetically modified maize MON 87427 × MON 89034 × NK603 and subcombinati…
2017
Scientific opinionRequestor: Competent Authority of BelgiumQuestion number: EFSA-Q-2013-00765; In this opinion, the EFSA Panel on Genetically Modified Organisms (GMO Panel) assessed the three-event stack maize MON 87427 9 MON 89034 9 NK603 and its three subcombinations, independently of their origin. The GMO Panel has previously assessed the three single events combined to produce this three-event stack maize and did not identify safety concerns. No new data on the single events, leading to modification of the original conclusions on their safety, were identified. Based on the molecular, agronomic, phenotypic and compositional characteristics, the combination of the single maize events and …
The Importance of Phytoplankton Biomolecule Availability for Secondary Production
2017
The growth and reproduction of animals is affected by their access to resources. In aquatic ecosystems, the availability of essential biomolecules for filter-feeding zooplankton depends greatly on phytoplankton. Here, we analyzed the biochemical composition, i.e., the fatty acid, sterol and amino acid profiles and concentrations as well as protein, carbon, nitrogen, and phosphorus content of 17 phytoplankton monocultures representing the seven most abundant phytoplankton classes in boreal and sub-arctic lakes. To examine how the differences in the biochemical composition between phytoplankton classes affect their nutritional quality for consumers, we assessed the performance of Daphnia, on …
Degradation of sexual reproduction in Veronica filiformis after introduction to Europe
2011
Abstract Background Baker’s law predicts that self-incompatible plant species are generally poor colonizers because their mating system requires a high diversity of genetically differentiated individuals and thus self-compatibility should develop after long-distance dispersal. However, cases like the introduction of the self-incompatible Veronica filiformis (Plantaginaceae) to Europe constitute an often overlooked alternative to this rule. This species was introduced from subalpine areas of the Pontic-Caucasian Mountains and colonized many parts of Central and Western Europe in the last century, apparently without producing seeds. To investigate the consequences of the absence of sexual rep…
Multiple‐batch spawning as a bet‐hedging strategy in highly stochastic environments: An exploratory analysis of Atlantic cod
2021
Stochastic environments shape life‐history traits and can promote selection for risk‐spreading strategies, such as bet‐hedging. Although the strategy has often been hypothesised to exist for various species, empirical tests providing firm evidence have been rare, mainly due to the challenge in tracking fitness across generations. Here, we take a ‘proof of principle’ approach to explore whether the reproductive strategy of multiple‐batch spawning constitutes a bet‐hedging. We used Atlantic cod (Gadus morhua) as the study species and parameterised an eco‐evolutionary model, using empirical data on size‐related reproductive and survival traits. To evaluate the fitness benefits of multiple‐batc…