Project description:13,300 year old (Satsurblia) and 9,700 year old (Kotias) genomes from western Georgia along with a 13,700 year old (Bichon) genome from Switzerland.
Project description:<p>Residues from ancient artifacts can help identify which plant species were used for their psychoactive properties, providing important information regarding the deep-time co-evolutionary relationship between plants and humans. However, relying on the presence or absence of one or several biomarkers has limited the ability to confidently connect residues to particular plants. We describe a comprehensive metabolomics-based approach that can distinguish closely related species and provide greater confidence in species use determinations. An approximately 1430-year-old pipe from central Washington State not only contained nicotine, but also had strong evidence for the smoking of <em>Nicotiana quadrivalvis</em> and <em>Rhus glabra</em>, as opposed to several other species in this pre-contact pipe. Analysis of a post-contact pipe suggested use of different plants, including the introduced trade tobacco, <em>Nicotiana rustica</em>. Ancient residue metabolomics provides a new frontier in archaeo-chemistry, with greater precision to investigate the evolution of drug use and similar plant-human co-evolutionary dynamics.</p>
Project description:Background: Salmonid species have followed markedly divergent evolutionary trajectories in their interactions with sea lice. While sea lice parasitism poses significant economic, environmental, and animal welfare challenges for Atlantic salmon (Salmo salar) aquaculture, coho salmon (Oncorhynchus kisutch) exhibit near-complete resistance to sea lice, achieved through a potent epithelial hyperplasia response leading to rapid louse detachment. The molecular mechanisms underlying these divergent responses to sea lice are unknown. Results: We characterised the cellular and molecular responses of Atlantic salmon and coho salmon to sea lice using single-nuclei RNA sequencing. Juvenile fish were exposed to copepodid sea lice (Lepeophtheirus salmonis), and lice-attached pelvic fin and skin samples were collected 12h, 24h, 36h, 48h, and 60h after exposure, along with control samples. Comparative analysis of control and treatment samples revealed an immune and wound-healing response that was common to both species, but attenuated in Atlantic salmon, potentially reflecting greater sea louse immunomodulation. Our results revealed unique but complementary roles of three layers of keratinocytes in the epithelial hyperplasia response leading to rapid sea lice rejection in coho salmon. Our results suggest that basal keratinocytes direct the expansion and mobility of intermediate and, especially, superficial keratinocytes, which eventually encapsulate the parasite. Conclusions: Our results highlight the key role of keratinocytes in coho salmon’s sea lice resistance, and the diverged biological response of the two salmonid host species when interacting with this parasite. This study has identified key pathways and candidate genes that could be manipulated using various biotechnological solutions to improve Atlantic salmon sea lice resistance.
Project description:This study investigates transcriptomic responses of Atlantic salmon lice, Lepeophtheirus salmonis exposed to cypermethrin, a commonly used antiparasitic agent used in aquaculture. Copepodid L. salmonis were exposed to cypermethrin (Betamax®) at a concentration of 1.0ppb An in vitro bioassay experiment was conducted using cypermethrin exposures on copepodid (larvae) sea lice (F1 generation) collected from BMA-2a New Brunswick, Canada in 2014. The bioassay exposed copepodids to 1.0 μg/L cypermethrin or a sea water control for 24 hours in glass beakers (VWR) at 12 ± 1oC. Each condition had a total volume of 500mL with six replicates and approximately 500 lice per beaker. After 24 hours, pools of ~500 copepodids were flash frozen for RNA extractions. Post 24-hours, lice were assessed for survival similarly to the technique used for staging and enumeratio first
Project description:This study investigates the baseline or inducible differences in between populations of Atlantic salmon lice Lepeophtheirus salmonis with differing levels of resistance to the parasiticidal drug emamectin benzoate (EMB), as well as the induced effects of EMB exposure to Pacific salmon lice. F1 generation lice were exposed in bioassays to a dilution series of emamectin benzoate.
Project description:This study investigates the baseline or inducible differences in between populations of Atlantic salmon lice Lepeophtheirus salmonis with differing levels of resistance to the parasiticidal drug emamectin benzoate (EMB), as well as the induced effects of EMB exposure to Pacific salmon lice. F1 generation lice were exposed in bioassays to a dilution series of emamectin benzoate. Two separate experiments were conducted, one for Atlantic and one for Pacific salmon lice (to be analyzed separately). Atlantic pre-adult salmon lice, separated into male and female, and sensitive or resistant to EMB populations, and exposed to a dilution series: 0 (control), 0.1, 25, 300, and 1000 parts per billion EMB. For each combination four biological replicates were included, except male resistant 25 (n = 3) and female resistant 300 (n = 2). Pacific pre-adult lice of both sexes were exposed to a dilution series: 0 (control), 25, 50 parts per billion EMB.
Project description:Gene order, or microsynteny, is generally thought not to be conserved across metazoan phyla. Only a handful of exceptions, typically of tandemly duplicated genes such as Hox genes, have been discovered. Here, we performed a systematic survey for microsynteny conservation in 17 genomes and identified nearly 600 pairs of unrelated genes that have remained together across over 600 million years of evolution. Using multiple genome-wide resources, including several genomic features, epigenetic marks, sequence conservation and microarray expression data, we provide extensive evidence that many of these ancient microsyntenic arrangements have been conserved in order to preserve either (i) the coordinated transcription of neighboring genes, or (ii) Genomic Regulatory Blocks (GRBs), in which transcriptional enhancers controlling key developmental genes are contained within nearby “bystander” genes. In addition, we generated ChIP-seq data for key histone modifications in zebrafish embryos to further investigate putative GRBs in embryonic development. Finally, using chromosome conformation capture (3C) assays and stable transgenic experiments, we demonstrate that enhancers within bystander genes drive the expression of genes such as Otx and Islet, critical regulators of central nervous system development across bilaterians. These results show that ancient genomic associations are far more common in modern metazoans than previously thought – likely involving over 12% of the ancestral bilaterian genome – and that cis-regulatory constraints have played a major role in conserving the architecture of metazoan genomes. ChIP-seq H3K27me3 of 24hpf zebrafish embryos
Project description:This study investigates sex-biased gene expression between populations of Atlantic and Pacific salmon lice, Lepeophtheirus salmonis. Two Atlantic L. salmonis populations were previously used for an array study (GSE56024) while a third dataset using Pacific L. salmonis was novel. Using all three populations, a consensus-based, meta-analysis approach was used to identify sex-biased and sex-specific genes. Two separate experiments were conducted, one for Atlantic and one for Pacific salmon lice. As the Atlantic data has been previously published for other comparisons (GSE56024), only the Pacific data is uploaded here. Lice from three populations (2 in the Atlantic and 1 in the Pacific) were collected for in vitro bioassay analysis using emamectin benzoate. After 24hrs, lice were collected as per treatment protocol below. Males and females from all populations were compared separately before forming a consensus probe list of sex-biased genes concordantly expressed across all three populations. Please note that each raw data file contains three or four 'block' data and each block data correspond to individual sample raw data. Therefore, each raw data file contains raw data for 3-4 samples (as indicated in the description field).