The naked mole-rat (NMR; ) is a eusocial subterranean rodent with a highly unusual set of physiological traits that has attracted great interest amongst the scientific community. However, the genetic basis of most of these traits has not been elucidated. To facilitate our understanding of the molecular mechanisms underlying NMR physiology and behaviour, we generated a long-read chromosomal-level genome assembly of the NMR.
View Article and Find Full Text PDFUnlabelled: The extent of interspecific gene flow and its consequences for the initiation, maintenance, and breakdown of species barriers in natural systems remain poorly understood. Interspecific gene flow by hybridization may weaken adaptive divergence, but can be overcome by selection against hybrids, which may ultimately promote reinforcement. An informative step towards understanding the role of gene flow during speciation is to describe patterns of past gene flow among extant species.
View Article and Find Full Text PDFThe human heart is poorly regenerative and cardiac tumors are extremely rare. Whether the adult zebrafish myocardium is responsive to oncogene overexpression and how this condition affects its intrinsic regenerative capacity remains unknown. Here, we have established a strategy of inducible and reversible expression of HRASG12V in zebrafish cardiomyocytes.
View Article and Find Full Text PDFIn contrast to mammals, zebrafish can regenerate their damaged photoreceptors. This capacity depends on the intrinsic plasticity of Müller glia (MG). Here, we identified that the transgenic reporter , a marker of regenerating fin and heart, also participates in retina restoration in zebrafish.
View Article and Find Full Text PDFCephalopods are set apart from other mollusks by their advanced behavioral abilities and the complexity of their nervous systems. Because of the great evolutionary distance that separates vertebrates from cephalopods, it is evident that higher cognitive features have evolved separately in these clades despite the similarities that they share. Alongside their complex behavioral abilities, cephalopods have evolved specialized cells and tissues, such as the chromatophores for camouflage or suckers to grasp prey.
View Article and Find Full Text PDFSimilar to human monocytes, bovine monocytes can be split into CD14CD16 classical, CD14CD16 intermediate and CD14CD16 nonclassical monocytes (cM, intM, and ncM, respectively). Here, we present an in-depth analysis of their steady-state bulk- and single-cell transcriptomes, highlighting both pronounced functional specializations and transcriptomic relatedness. Bulk gene transcription indicates pro-inflammatory and antibacterial roles of cM, while ncM and intM appear to be specialized in regulatory/anti-inflammatory functions and tissue repair, as well as antiviral responses and T-cell immunomodulation.
View Article and Find Full Text PDFThis study was initiated to better understand the nature of innate immune responses and the relatively weak and delayed immune response against porcine reproductive and respiratory syndrome virus (PRRSV). Following modified live virus (MLV) vaccination or infection with two PRRSV-2 strains, we analyzed the transcriptome of peripheral blood mononuclear cells collected before and at three and seven days after vaccination or infection. We used blood transcriptional modules (BTMs)-based gene set enrichment analyses.
View Article and Find Full Text PDFIn the venom of spiders, linear peptides (LPs), also called cytolytical or antimicrobial peptides, represent a largely neglected group of mostly membrane active substances that contribute in some spider species considerably to the killing power of spider venom. By next-generation sequencing venom gland transcriptome analysis, we investigated 48 spider species from 23 spider families and detected LPs in 20 species, belonging to five spider families (Ctenidae, Lycosidae, Oxyopidae, Pisauridae, and Zodariidae). The structural diversity is extraordinary high in some species: the lynx spider contains 62 and the lycosid 60 different LPs.
View Article and Find Full Text PDFDarwinian evolution preferentially follows mutational pathways whose individual steps increase fitness. Alternative pathways with mutational steps that do not increase fitness are less accessible. Here, we show that mistranslation, the erroneous incorporation of amino acids into nascent proteins, can increase the accessibility of such alternative pathways and, ultimately, of high fitness genotypes.
View Article and Find Full Text PDFIdentifying local adaptation in bottlenecked species is essential for conservation management. Selection detection methods have an important role in species management plans, assessments of adaptive capacity, and looking for responses to climate change. Yet, the allele frequency changes exploited in selection detection methods are similar to those caused by the strong neutral genetic drift expected during a bottleneck.
View Article and Find Full Text PDFCanine intervertebral disc disease (IVDD) represents a significant clinical problem in veterinary medicine, with similarities to the human pathology. Host-derived damage-associated molecular patterns like fibronectin fragments (FnF) that develop during tissue dysfunction may be of specific relevance to IVD pathologies by inducing an inflammatory response in resident cells. This project aimed to determine the presence and pathobiological role of FnF during IVD herniation in dogs, with a focus on inflammation.
View Article and Find Full Text PDFPolyploidization is pervasive in plants, but little is known about the niche divergence of wild allopolyploids (species that harbor polyploid genomes originating from different diploid species) relative to their diploid progenitor species and the gene expression patterns that may underlie such ecological divergence. We conducted a fine-scale empirical study on habitat and gene expression of an allopolyploid and its diploid progenitors. We quantified soil properties and light availability of habitats of an allotetraploid Cardamine flexuosa and its diploid progenitors Cardamine amara and Cardamine hirsuta in two seasons.
View Article and Find Full Text PDFDendritic cells (DC) and monocytes are vital for the initiation of innate and adaptive immune responses. Recently, we identified bona fide DC subsets in blood of cattle, revealing subset- and species-specific transcription of toll-like receptors (TLR). In the present study, we analyzed phenotypic and transcriptional responses of bovine DC subsets and monocytes to in vitro stimulation with four to six different TLR ligands.
View Article and Find Full Text PDFIn domestic goats, the polled intersex syndrome (PIS) refers to XX female-to-male sex reversal associated with the absence of horn growth (polled). The causal variant was previously reported as a 11.7 kb deletion at approximately 129 Mb on chromosome 1 that affects the transcription of both FOXL2 and several long non-coding RNAs.
View Article and Find Full Text PDFGenome duplication is widespread in wild and crop plants. However, little is known about genome-wide selection in polyploids due to the complexity of duplicated genomes. In polyploids, the patterns of purifying selection and adaptive substitutions may be affected by masking owing to duplicated genes or homeologs as well as effective population size.
View Article and Find Full Text PDFThe reconstruction of ancient metagenomes from archaeological material, and their implication in human health and evolution, is one of the most recent advances in paleomicrobiological studies. However, as for all ancient DNA (aDNA) studies, environmental and laboratory contamination need to be specifically addressed. Here we attempted to reconstruct the tissue-specific metagenomes of a 42,000-year-old, permafrost-preserved woolly mammoth calf through shotgun high-throughput sequencing.
View Article and Find Full Text PDFHigh-throughput sequencing is a powerful tool, but suffers biases and errors that must be accounted for to prevent false biological conclusions. Such errors include batch effects; technical errors only present in subsets of data due to procedural changes within a study. If overlooked and multiple batches of data are combined, spurious biological signals can arise, particularly if batches of data are correlated with biological variables.
View Article and Find Full Text PDFBMC Bioinformatics
November 2017
Background: The development of next-generation sequencing has made it possible to sequence whole genomes at a relatively low cost. However, de novo genome assemblies remain challenging due to short read length, missing data, repetitive regions, polymorphisms and sequencing errors. As more and more genomes are sequenced, reference-guided assembly approaches can be used to assist the assembly process.
View Article and Find Full Text PDFBackground: The purpose of gene set enrichment analysis (GSEA) is to find general trends in the huge lists of genes or proteins generated by many functional genomics techniques and bioinformatics analyses.
Results: Here we present SetRank, an advanced GSEA algorithm which is able to eliminate many false positive hits. The key principle of the algorithm is that it discards gene sets that have initially been flagged as significant, if their significance is only due to the overlap with another gene set.
Phylogenetic reconstruction of the evolutionary history of closely related organisms may be difficult because of the presence of unsorted lineages and of a relatively high proportion of heterozygous sites that are usually not handled well by phylogenetic programs. Genomic data may provide enough fixed polymorphisms to resolve phylogenetic trees, but the diploid nature of sequence data remains analytically challenging. Here, we performed a phylogenomic reconstruction of the evolutionary history of the common vole (Microtus arvalis) with a focus on the influence of heterozygosity on the estimation of intraspecific divergence times.
View Article and Find Full Text PDFUnlabelled: The analysis of genetic data often requires a combination of several approaches using different and sometimes incompatible programs. In order to facilitate data exchange and file conversions between population genetics programs, we introduce PGDSpider, a Java program that can read 27 different file formats and export data into 29, partially overlapping, other file formats. The PGDSpider package includes both an intuitive graphical user interface and a command-line version allowing its integration in complex data analysis pipelines.
View Article and Find Full Text PDFWe present here a new version of the Arlequin program available under three different forms: a Windows graphical version (Winarl35), a console version of Arlequin (arlecore), and a specific console version to compute summary statistics (arlsumstat). The command-line versions run under both Linux and Windows. The main innovations of the new version include enhanced outputs in XML format, the possibility to embed graphics displaying computation results directly into output files, and the implementation of a new method to detect loci under selection from genome scans.
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