Search results for "genome"
showing 10 items of 1913 documents
Soil features in rookeries of Antarctic penguins reveal sea to land biotransport of chemical pollutants
2017
© The Author(s).
A mitogenome sequence of an Equus hydruntinus specimen from Late Quaternary site of San Teodoro Cave (Sicily, Italy)
2020
Abstract Equus hydruntinus was a small equid that ranged from the Iberian Peninsula to Middle East. In Italy it has been considered present from the Middle Pleistocene to its extinction in the Middle-Late Holocene. E. hydruntinus shares plesiomorphic traits with other known Pleistocene equids. As a consequence, its classification has always been problematic. Genetic analyses on few fossil remains from Iran and Crimea have revealed that E. hydruntinus was more closely related to extant hemiones. To further investigate its systematic position, using target-enrichment capture and next-generation sequencing, we reconstructed a near complete mitogenome of a specimen from San Teodoro Cave from Si…
The genomic history of the Iberian Peninsula over the past 8000 years
2019
We assembled genome-wide data from 271 ancient Iberians, of whom 176 are from the largely unsampled period after 2000 BCE, thereby providing a high-resolution time transect of the Iberian Peninsula. We document high genetic substructure between northwestern and southeastern hunter-gatherers before the spread of farming. We reveal sporadic contacts between Iberia and North Africa by ~2500 BCE and, by ~2000 BCE, the replacement of 40% of Iberia's ancestry and nearly 100% of its Y-chromosomes by people with Steppe ancestry. We show that, in the Iron Age, Steppe ancestry had spread not only into Indo-European-speaking regions but also into non-Indo-European-speaking ones, and we reveal that pre…
Genomic transformation and social organization during the Copper Age–Bronze Age transition in southern Iberia
2021
Description
Drastic Genome Reduction in an Herbivore's Pectinolytic Symbiont.
2017
Pectin, an integral component of the plant cell wall, is a recalcitrant substrate against enzymatic challenges by most animals. In characterizing the source of a leaf beetle’s (Cassida rubiginosa) pectin-degrading phenotype, we demonstrate its dependency on an extracellular bacterium housed in specialized organs connected to the foregut. Despite possessing the smallest genome (0.27 Mb) of any organism not subsisting within a host cell, the symbiont nonetheless retained a functional pectinolytic metabolism targeting the polysaccharide’s two most abundant classes: homogalacturonan and rhamnogalacturonan I. Comparative transcriptomics revealed pectinase expression to be enriched in the symbiot…
Linking species habitat and past palaeoclimatic events to evolution of the teleost innate immune system
2017
Host-intrinsic factors as well as environmental changes are known to be strong evolutionary drivers defining the genetic foundation of immunity. Using a novel set of teleost genomes and a time-calibrated phylogeny, we here investigate the family of Toll-like receptor ( TLR ) genes and address the underlying evolutionary processes shaping the diversity of the first-line defence. Our findings reveal remarkable flexibility within the evolutionary design of teleost innate immunity characterized by prominent TLR gene losses and expansions. In the order of Gadiformes, expansions correlate with the loss of major histocompatibility complex class II ( MHCII ) and diversifying selection analyses sup…
Stabilizing selection on microsatellite allele length at arginine vasopressin 1a receptor and oxytocin receptor loci
2017
The loci arginine vasopressin receptor 1a ( avpr1a ) and oxytocin receptor ( oxtr ) have evolutionarily conserved roles in vertebrate social and sexual behaviour. Allelic variation at a microsatellite locus in the 5′ regulatory region of these genes is associated with fitness in the bank vole Myodes glareolus . Given the low frequency of long and short alleles at these microsatellite loci in wild bank voles, we used breeding trials to determine whether selection acts against long and short alleles. Female bank voles with intermediate length avpr1a alleles had the highest probability of breeding, while male voles whose avpr1a alleles were very different in length had reduced probability of …
Ecological genomics of adaptation to unpredictability in experimental rotifer populations
2019
AbstractElucidating the genetic basis of phenotypic variation in response to different environments is key to understanding how populations evolve. Facultatively sexual rotifers can develop adaptive responses to fluctuating environments. In a previous evolution experiment, diapause-related traits changed rapidly in response to two selective regimes (predictable vs unpredictable) in laboratory populations of the rotifer Brachionus plicatilis. Here, we investigate the genomic basis of adaptation to environmental unpredictability in these experimental populations. We identified and genotyped genome-wide polymorphisms in 169 clones from both selective regimes after seven cycles of selection usi…
Ocean acidification at a coastal CO2 vent induces expression of stress-related transcripts and transposable elements in the sea anemone Anemonia viri…
2019
Published version, available at: https://doi.org/10.1371/journal.pone.0210358 Ocean acidification threatens to disrupt interactions between organisms throughout marine ecosystems. The diversity of reef-building organisms decreases as seawater CO2 increases along natural gradients, yet soft-bodied animals, such as sea anemones, are often resilient. We sequenced the polyA-enriched transcriptome of adult sea anemone Anemonia viridis and its dinoflagellate symbiont sampled along a natural CO2 gradient in Italy to assess stress levels in these organisms. We found that about 1.4% of the anemone transcripts, but only ~0.5% of the Symbiodinium sp. transcripts were differentially expressed. Processe…
Thalassocella blandensis gen. nov., sp. nov., a novel member of the family Cellvibrionaceae
2020
9 pages, 1 figure, 3 tables