Project description:The gut microbiome consists of trillions of bacteria, fungi, and viruses that inhabit the digestive tract. These communities are sensitive to disruption from environmental exposures ranging from diet changes to illness. Disruption of the community of lactic acid producing bacteria, Lactobaccillacea, has been well documented in mood disorders and stress exposure. In fact, oral supplement with many Lactobacillus species can ameliorate these effects, preventing depression- and anxiety-like behavior. Here, we utilize a gnotobiotic mouse colonized with the Altered Schaedler Flora to remove the two native species of Lactobaccillacea. Using this novel microbial community, we found that the Lactobacillus species themselves, and not the disrupted microbial communities are protective from environmental stressors. Further, we determine that Lactobaccillacea are maintaining homeostatic IFNγ levels which are mediating these behavioral and circuit level responses. By utilizing the Altered Schaedler Flora, we have gained new insight into how probiotics influence behavior and provide novel methods to study potential therapies to treat mood disorders.
Project description:The diatoms Thalassiosira hyalina and Nitzschia frigida are important members of Arctic pelagic (open-water) and sympagic (ice-associated) microalgal communities. We investigated here the molecular mechanisms these algae apply to cope with abrupt high light exposure (Shift from 20 to 380 µmol photons m-2 s-1, resembling upwelling or ice break-up). Experiments were done under contemporary as well as future pCO2 (400 vs. 1000 µatm) to investigate whether [CO2] or pH modulate the reactions to high light intensities. After proper acclimation to the low-light regime, cells were sampled (= 0 hours), then exposed to the high-light treatment expression patterns were followed over 120h. Transcriptomic data were discussed also in the light of an accompanying physiological dataset from the same experiment (Ane Kvernvik et al. in prep).
