 Erin Hamilton, M. Sc. Candidate
The Towards a Sustainable Fishery for Nunavummiut (TSFN) Project is partnered with the Nunavut community of Gjoa Haven. We are using genomic and microbial analyses to inform strategies to retain genetically-diverse and healthy fish stocks for Inuit communities. In this region, Arctic char (Salvelinus alpinus) and whitefish (Coregonus spp.) can be anadromous, migrating annually from the ocean to freshwater lakes and rivers in order to escape sub-zero temperatures. The fish and their associated microbiomes must adapt accordingly to their changing environment. Analysis of fish microbial community compositions has shown that skin bacterial communities are statistically different when sampled from freshwater or saline water sites, but appear to maintain a core community, with Proteobacteria, Firmicutes, and Cyanobacteria presenting as major phyla. Given these findings, microbial assemblages could be used as a proxy for fish health. In addition, there is bioprospecting potential for microbial taxa that could provide advantages for fish in aquaculture.  Dr. Matsuo Uemura, Faculty of Agriculture, Iwate University, Morioka, Japan
Freezing stress is one of the most important limiting factors of plant survival. Plants have developed a freezing adaptation mechanism upon sensing low temperatures (cold-acclimation). Compositional changes in the plasma membrane, one of the initial sites of freezing injury, is prerequisite of achieving cold acclimation and have been investigated in several plant species. However, the cold dehardening process at elevated temperatures (de-acclimation) has not yet been fully characterized. Here we conducted shotgun proteomics with label-free semiquantification on plasma membrane fractions of Arabidopsis leaves during cold acclimation and de-acclimation. A list of 873 proteins with significantly changed proteins in response to the two processes was obtained. Although the cold-acclimation-responsive proteins were globally returned to non-acclimated levels by de-acclimation, several representative cold-acclimation-responsive proteins tended to remain at higher abundance during de-acclimation process. Our results suggest that plants deharden right after cold acclimation to restart growth and development but some protein changes of the plasma membrane may be maintained to cope with the threat of sudden freezing during deacclimation process. |
