Project description:Transcriptional profiling of populations in the clam Ruditapes decussatus determined differentiation in gene-expression along parallel temperature gradients and between races of the Atlantic Ocean and West Mediterranean sea.
Project description:The available energy and carbon sources for prokaryotes in the deep ocean remain still largely enigmatic. Reduced sulfur compounds, such as thiosulfate, are a potential energy source for both auto- and heterotrophic marine prokaryotes. Shipboard experiments performed in the North Atlantic using Labrador Sea Water (~2000 m depth) amended with thiosulfate led to an enhanced prokaryotic dissolved inorganic carbon (DIC) fixation.
Project description:An Autonomous Underwater Vehicle (AUV) and large volume underwater pumps were used to collect microbial biomass from offshore waters of the Sargasso Sea, from surface waters and into the deep ocean. Seawater collection was performed along a transect in the western North Atlantic Ocean beginning near Bermuda and ending off the coast of Massachusetts, capturing metabolic signatures from oligotrophic, continental margin, and productive coastal ecosystems.
Project description:The largest of the tuna species, Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758), inhabits the North Atlantic Ocean and the Mediterranean Sea and is considered to be an endangered species, largely through overfishing. Thus, the development of aquaculture practices independent of wild resources can provide an important contribution towards ensuring security and sustainability of this species in the longer-term. In order to provide a resource for ongoing studies, we have used 454 pyrosequencing technology to sequence a mixed-tissue normalized cDNA library, derived from adult individuals. Transcript sequences were used to develop a novel 15K Agilent oligo microarray for T. thynnus and comparative tissue gene expression profiles were inferred for gill, heart, liver, ovaries and testes.
Project description:The loss of biodiversity is increasingly well understood on land, but trajectories of extinction risk remain largely unknown in the ocean. We present regional Red List Indices (RLIs) to track the extinction risk of 119 Northeast Atlantic and 72 Mediterranean shark and ray species primarily threatened by overfishing. We combine two IUCN workshop assessments from 2003/2005 and 2015 with a retrospective backcast assessment for 1980. We incorporate predicted categorisations for Data Deficient species from our previously published research. The percentage of threatened species rose from 1980 to 2015 from 29 to 41% (Northeast Atlantic) and 47 to 65% (Mediterranean Sea). There are as many threatened sharks and rays in Europe as there are threatened birds, but the threat level is nearly six times greater by percentage (41%, n = 56 of 136 vs. 7%, n = 56 of 792). The Northeast Atlantic RLI declined by 8% from 1980 to 2015, while the higher-risk Mediterranean RLI declined by 13%. Larger-bodied, shallow-distributed, slow-growing species and those with range boundaries within the region are more likely to have worsening status in the Northeast Atlantic. Conversely, long-established, severe threat levels obscure any potential relationships between species' traits and the likelihood of worsening IUCN status in the Mediterranean Sea. These regional RLIs provide the first widespread evidence for increasing trends in regional shark and ray extinction risk and underscore that effective fisheries management is necessary to recover the ecosystem function of these predators.
Project description:Parasite biodiversity in cetaceans represents a neglected component of the marine ecosystem. This study aimed to investigate the distribution and genetic diversity of anisakid nematodes of the genus Anisakis sampled in cetaceans from the Northeast Atlantic Ocean and the Mediterranean Sea. A total of 478 adults and pre-adults of Anisakis spp. was identified by a multilocus genetic approach (mtDNA cox2, EF1 α - 1 nDNA and nas 10 nDNA gene loci) from 11 cetacean species. A clear pattern of host preference was observed for Anisakis spp. at cetacean family level: A. simplex (s.s.) and A. pegreffii infected mainly delphinids; A. physeteris and A. brevispiculata were present only in physeterids, and A. ziphidarum occurred in ziphiids. The role of cetacean host populations from different waters in shaping the population genetic structure of A. simplex (s.s.), A. pegreffii and A. physeteris was investigated for the first time. Significant genetic sub-structuring was found in A. simplex (s.s.) populations of the Norwegian Sea and the North Sea compared to those of the Iberian Atlantic, as well as in A. pegreffii populations of the Adriatic and the Tyrrhenian Seas compared to those of the Iberian Atlantic waters. Substantial genetic homogeneity was detected in the Mediterranean Sea population of A. physeteris. This study highlights a strong preference by some Anisakis spp. for certain cetacean species or families. Information about anisakid biodiversity in their cetacean definitive hosts, which are apex predators of marine ecosystems, acquires particular importance for conservation measures in the context of global climate change phenomena.
Project description:The Atlantic cod (Gadus morhua L.) is one of the most important species in the Baltic Sea with high ecological and economical value. To explore the differences in adaptation to salinity between Baltic cod from different regions, western (Kiel Bight) and eastern (Gdańsk Bay) samples were analyzed through oligonucleotide microarray.
Project description:This dataset consists of 20 metaproteomic analyses of the Western Atlantic Ocean aboard the R/V Knorr KN210-04 DeepDOM expedition in 2013. Samples were collected by McLane pumps on GFF or GF75 filters, split, and frozen until analyses. Expedition metadata and co-sampled datasets are available at: https://www.bco-dmo.org/deployment/59057
Project description:Ocean acidification is recognized as one of the most pervasive anthropogenic impact on marine life. A variety of responses have been highlighted in different marine organisms ranging from physiology to gene and protein expression. However, most of these studies have been performed in laboratory exposing adults or developmental stages to CO2 enriched seawater. To what extend the information obtained from these in vitro experiments may be extrapolated to a natural environment is questionable. Here, we utilized the Castello volcanic CO2 vents at Ischia as natural laboratory to study the P. lividus population living at the low pH zone (pH~7.8) compared to those of sea urchins living at control sites. Wide-ranging analyses were performed in animals collected at the acidified site, including the monitoring of their position, the determination of the physico-chemical parameters of the coelomic fluid and an in depth characterization of coelomocytes regarding the number and type of cells, Hsp70 expression, redox status and protein expression through de-novo sequencing analyses. In addition, the respiration, nitrogen metabolism, and skeletal mineralogy of urchins from the vent were examined in comparison with those from control animals. Overall these analyses allowed to understand how the sea urchins can thrive in low pH/high CO2.
Project description:In this study, transcriptomics was used to investigate Atlantic salmon (Salmo salar) sampled from three different field locations within Baltic Sea (Baltic Main Basin (CBS), Gulf of Finland (GoF) and Bothnian Sea (BS)) during marine migration. RNA labeling, hybridizations, and scanning were performed by the Finnish Microarray and Sequencing Centre in Turku Centre for Biotechnology.