TMT-Based Proteomic Profiling Reveals the Molecular Mechanism in the Cold Tolerance of Rhododendron Aureum Georgi.

Background: Cold stress is one of the important factors that restrict plant growth and regional distribution. Under cold acclimation conditions, plants growing in temperate zones reprogram the gene expression in the cells, making the plants better cope with the coming cold stress. However, under natural environmental conditions, the climate is complex and changeable. The sudden large temperature drop will bring serious disasters to plants. Rhododendron aureum Georgi, as an evergreen plant growing in high altitude areas of Changbai Mountain, the harsh ecological environment may endow it with different cold tolerance characteristics. Results: In this study, the proteomic difference between samples under control and cold stress were compared pairwise. A total of 360 DAPs were identified, of which 175 were down-regulated and 185 were up-regulated when comparing these two sets of data. The high cold tolerance of Rhododendron plants can be attributed to: accumulation of chaperone proteins; the up-regulation of components related to translation; enhancement of catabolism and reduction in anabolism, provide energy for plants and fight against cold stress; enhanced cellular antioxidant capacity; modification of components in cell wall, membrane, and cytoskeleton. Conclusion: These results provide an in-depth understanding of the cold tolerance mechanism of Rhododendron. The identified genes and metabolic pathways provide a certain reference for the genetic improvement of plant cold tolerance.