Proteome Analysis of Cold Response in Spring and Winter Wheat (<i>Triticum aestivum</i>) Crowns Reveals Similarities in Stress Adaptation and Differences in Regulatory Processes between the Growth Habits

A proteomic response to cold treatment (4 °C) has been studied in crowns of a frost-tolerant winter wheat cultivar Samanta and a frost-sensitive spring wheat cultivar Sandra after short-term (3 days) and long-term (21 days) cold treatments. Densitometric analysis of 2-D differential in gel electrophoresis (2D-DIGE) gels has resulted in the detection of 386 differentially abundant protein spots, which reveal at least a two-fold change between experimental variants. Of these, 58 representative protein spots have been selected for MALDI-TOF/TOF identification, and 36 proteins have been identified. The identified proteins with an increased relative abundance upon cold in both growth habits include proteins involved in carbohydrate catabolism (glycolysis enzymes), redox metabolism (thioredoxin-dependent peroxidase), chaperones, as well as defense-related proteins (protein revealing similarity to thaumatin). Proteins exhibiting a cold-induced increase in the winter cultivar include proteins involved in regulation of stress response and development (germin E, lectin VER2), while proteins showing a cold-induced increase in the spring cultivar include proteins involved in restoration of cell division and plant growth (eIF5A2, glycine-rich RNA-binding protein, adenine phosphoribosyltransferase). These results provide new insights into cold acclimation in spring and winter wheat at the proteome level and enrich our previous work aimed at phytohormone dynamics in the same plant material.