Project description:The Baltic Sea is one of the largest brackish water bodies in the world. Redoxclines that form between oxic and anoxic layers in the deepest sub-basins are a semi-permanent character of the pelagic Baltic Sea. The microbially mediated nitrogen removal processes in these redoxclines have been recognized as important ecosystem service that removes large proportion of the nitrogen load originating from the drainage basin. However, nitrification, which links mineralization of organic nitrogen and nitrogen removal processes, has remained poorly understood. To gain better understanding of the nitrogen cycling in the Baltic Sea, we analyzed the assemblage of ammonia oxidizing bacteria and archaea in the central Baltic Sea using functional gene microarrays and measured the biogeochemical properties along with potential nitrification rates. Overall, the ammonia oxidizer communities in the Baltic Sea redoxcline were very evenly distributed. However, the communities were clearly different between the eastern and western Gotland Basin and the correlations between different components of the ammonia oxidizer assemblages and environmental variables suggest ecological basis for the community composition. The more even community ammonia oxidizer composition in the eastern Gotland Basin may be related to the constantly oscillating redoxcline that does not allow domination of single archetype. The oscillating redoxcline also creates long depth range of optimal nitrification conditions. The rate measurements suggest that nitrification in the central Baltic Sea is able to produce all nitrate required by denitrification occurring below the nitrification zone. Two color array (Cy3 and Cy5): the universal standard 20-mer oligo is printed to the slide with a 70-mer oligo (an archetype). Environmental DNA sequences (fluoresced with Cy3) within 15% of the 70-mer conjugated to a 20-mer oligo (fluoresced with Cy5) complementary to the universal standard will bind to the oligo probes on the array. Signal is the ratio of Cy3 to Cy5. Three replicate probes were printed for each archetype. Two replicate arrays were run on duplicate targets.
Project description:The interaction of animals with microbes relies on the specific recognition of microbial-derived molecules by receptors of the immune system. Sponges (phylum Porifera), as sister group of the Eumetazoa, provide insights into conserved mechanisms for animal-microbe crosstalk, but empirical data is limited. Here we aimed to characterize the immune response of sponges upon microbial stimuli by RNA-Seq. Two sponges species from the Mediterranean Sea, Aplysina aerophoba and Dysidea avara, were challenged with microbial-associated molecular patterns (lipopolysaccharide and peptidoglycan) or sterile artificial seawater (control) in aquarium experiments. Sponge tissue samples were collected 1h, 3h, and 5h after treatment. The response of the sponges to the treatments was assessed by differential gene expression analysis of RNA-Seq data. For each species, we compared the transcriptomic profiles of the samples in MAMP treatment to control within each time point.
Project description:Bathymodiolus azoricus is a deep-sea mussel found in the hydrothermal vent fields of the Mid-Atlantic Ridge. It lives in symbiosis with sulfur- and methane-oxidizing γ-proteobacteria within its gills. In our study, we aimed to understand the metabolic and physiological interconnections between the symbiotic partners. For this purpose, symbionts and host were physically separated using density gradient centrifugation. This procedure yielded a symbiont-enriched gradient pellet fraction and a supernatant fraction enriched in host components. The cytosolic and membrane-associated proteome of both these fractions along with whole gill and foot tissue of the mussel were then investigated through 1D-PAGE LC-MS/MS. Proteins were quantified based on their spectral counts using the NSAF method. For efficient identification, sequences from evolutionarily related endosymbiotic and free-living bacteria and from bivalve host relatives were compiled into a comprehensive protein database. A total of 3178 host and symbiont proteins were identified from all samples.
2016-10-06 | PXD004061 | Pride
Project description:Prokaryote populations of extant microbialites along a depth gradient in Pavilion Lake, British Columbia, Canada
Project description:Microtus fortis (M. fortis) is the only mammal in which the growth, development and maturation of schistosomes (Schistosoma japonicum) is prevented, resulting in the failure of the parasite to mature and complete its life cycle. MicroRNAs (miRNAs) are a class of endogenous, non-coding small RNAs, has been found to introduce a whole new layer of gene regulation in eukaryotes. The anti-schistosomiasis mechanosm of M. fortis may require the participation of miRNA-mediated gene expression. In the present study, the difference pathological change of different tissue such as liver, spleen and lung of M. fortis were observed by using haematoxylin-eosin staining. Also, the miRNA expression in different tissue of M. fortis and mice before challenge and 10 days post-infection with schistosomes were first compared using microRNA microarray analysis. Histological analyses showed that S. japonicum infection in M. fortis resulted in more intensive inflammatory response and pathologic change than mice. The microarray investigations showed that 388 miRNAs detected common expressed in the two species, and 11 miRNAs in liver, 25 miRNAs in spleen and 28 miRNAs in lung differentially expressed in non-permissive M. fortis while increased, decreased or nearly fixed in mice. Further studies of the differentially expressed miRNAs demonstrated that many important signal pathway were triggered after the S. japonicum infection in M. fortis rather than the mouse, such as the metabolism of some nutrient material such as fatty-acid, cholesterol, lipid, insulin, and carbohydrate; immune response such as B and T cell differentiation, monocyte differentiation, the inflammation, NF-kappaB binding, even the in innate immune system; Cell differentiation and apoptosis such as erythrocytic differentiation and targeting proapoptotic and antiapoptotic proteins. These results may provide new insights into general mechanisms of regulation in non-permissive M. fortis, exploit the potential miRNA regulatory networks and the interaction between parasites and different hosts, which provide valuable new information on schistosome biology and valuable information for the better understanding of schistosome development and host-parasite interactions. We collected liver, spleen and lung from control and 10 days post-infection with schistosomes of M. fortis, mice and rat, respectively.