Friday, Feb 22, 11:30-12:30 // Temporal changes of Arabidopsis plasma membrane proteome during cold- and de-acclimation
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.