Project description:We sampled the microbial community at the sea ice edge in McMurdo Sound, Ross Sea at the same location (-77.62S, 165.41E) for four weeks (as described in Wu et al 2019, Nat. Comms.). We had four sampling dates corresponding to weeks 1 to 4: December 28 2014, January 6, 15, and 22 2015. Large volumes of water (150--250 L) were filtered from 1 m depth at the sea ice edge, and passed through three filters sequentially (3.0, 0.8, and 0.1 um, each 293 mm Supor filters). Filters with collected biomass were then placed in tubes with a sucrose-based preservative buffer (20 mM EDTA, 400 mM NaCl, 0.75 M sucrose, 50 mM Tris-HCl, pH 8.0) and stored at -80 C until sample processing. We extracted proteins after buffer exchange into a 3\% SDS solution as previously described Wu et al 2019, Nat. Comms.
Project description:Iron accumulation in microglia has been observed in Alzheimer’s disease and other neurodegenerative disorders and is thought to contribute to disease progression through various mechanisms including neuroinflammation. To study the interaction between iron accumulation and inflammation, we treated human induced pluripotent stem cell-derived microglia (iPSC-MG) with an increasing concentration of iron, in combination with inflammatory stimuli such as interferon gamma and amyloid β, and performed RNA sequencing.
Project description:A changing climate is altering many ocean properties that consequently will modify marine productivity. Previous phytoplankton manipulation studies have focused on individual or subsets of these properties. Here, we investigate the cumulative effects of multi-faceted change on a subantarctic diatom Pseudonitzschia multiseries by concurrently manipulating five stressors (light/nutrients/CO2/temperature/iron) that primarily control its physiology, and explore underlying reasons for altered physiological performance. Climate change enhances diatom growth mainly owing to warming and iron enrichment, and both properties decrease cellular nutrient quotas, partially offsetting any effects of decreased nutrient supply by 2100. Physiological diagnostics and comparative proteomics demonstrate the joint importance of individual and interactive effects of temperature and iron, and reveal biased future predictions from experimental outcomes when only a subset of multi-stressors is considered. Our findings for subantarctic waters illustrate how composite regional studies are needed to provide accurate global projections of future shifts in productivity and distinguish underlying species-specific physiological mechanisms.