ABSTRACT: Surveying marine biodiversity using eDNA metabarcoding of seawater and sediment in a high Arctic fjord during the polar night (Kongsfjorden, Svalbard)
Project description:Monitoring microbial communities can aid in understanding the state of these habitats. Environmental DNA (eDNA) techniques provide efficient and comprehensive monitoring by capturing broader diversity. Besides structural profiling, eDNA methods allow the study of functional profiles, encompassing the genes within the microbial community. In this study, three methodologies were compared for functional profiling of microbial communities in estuarine and coastal sites in the Bay of Biscay. The methodologies included inference from 16S metabarcoding data using Tax4Fun, GeoChip microarrays, and shotgun metagenomics.
Project description:Polar cod (Boreogadus saida), a key arctic fish species spawning during the polar night, may be at risk for crude oil exposure during this potential sensitive life stage. This study investigates the effects of crude oil exposure on Polar cod during spawning season. Wild-caught polar cod were exposed to crude oil water accommodated fraction (WAF) (start concentrations of sum of 44 polycyclic aromatic hydrocarbon (sum 44 PAHs) at 12.5 μg/L) from pre-spawning to post-spawning. The exposure system consisted of an oiled-rock-column system where running though sweater delivers WAF in the fish tank at decreasing concentrations over time. Samples were taken at three time-points (pre-spawning, spawning window, and post-spawning) and used to evaluate changes in reproductive endpoints such as gonad histology, plasma steroid hormones and sperm motility. For RNA-extraction and sequencing, liver samples from both oil-exposed and control groups of female fish (n = 5 per group) were taken at 47 days after experiment start and submitted for sequencing. RNA-seq analysis showed that hundreds of genes were differentially expressed in the liver.
Project description:We report here the release of a multi organ transcriptome developped for the Arctic char Salvelinus alpinus. This reference set was obtained using the 454 GS FLX+ technology. A pool of one-year-old, immature offspring of wild, anadromous Arctic charr originating from Lake Varflusjoen, Svalbard (79oN), including both lean and fat individuals, and three-years-old mature offspring of charr originating from Lake Vårflusjøen, North-Norway (70oN) was sampled. In order to maximize the diversity of expressed transcripts, we sampled a variety of organs and tissues; the whole brain, gill and head kidney and pieces of the liver, gonad, abdominal fat and muscle.
Project description:Prokarytoic 16S rRNA gene metabarcoding with Svalbard fjord seawaters in 2019
| PRJNA669167 | ENA
Project description:Eukaryotic 18S rRNA gene metabarcoding with Svalbard fjord seawaters in 2019
| PRJNA669202 | ENA
Project description:Ecological interaction between bacteriophages and bacteria community during the early white night and mid-summer in Sub-arctic Kongsfjorden bay of Svalbard (Norway)
| PRJNA1048555 | ENA
Project description:Biodiversity assessment of coastal lagoon through eDNA metabarcoding
Project description:Polar cod, a key fish species in the arctic marine foodweb is vulnerable to effects of pollution from offshore petroleum related activities in the Arctic and sub-arctic region. The study was conducted to map transcriptome responses to in Polar cod (Boreogadus saida) liver slice culture exposed to benzo[a]pyrene (BaP) in the presence or absence of physiological levels of ethynylestradiol (EE2). BaP is a polycyclic aromatic hydrocarbon (PAH), also found in crude oil contaminants. PAHs such as BaP are among the most toxic compounds of crude oil. Precision-cut liver slice cultures from five female polar cod (n = 5/ group, paired design) were exposed to BaP alone (10 µM), or in combination with low concentrations of EE2 (5 nM), to mimic physiological estradiol levels in early vitellogenic female fish. Transcriptome analysis (RNA-seq) was performed after 72 h exposure in culture. The results provide a global view of transcriptome responses to BaP, EE2 and their mixture. In the mixture exposure, BaP resulted attenuation of EE2 stimulated gene expression (anti-estrogenic effects). The results from this ex vivo experiment suggest that pollutants that activate the Ahr pathway such as the PAH compound BaP can result in anti-estrogenic effects that may lead to endocrine disruption in polar cod.