Changes of protein expression during leaves of shrub willow clones in response to salt stress

Abstract

Salt in saline land is regarded as a kind of abiotic stress that limits the productivity of plants and their geographical distribution. To understand the mechanism of how shrub willow clones seedling respond to salt stress at the proteomic level, proteins extracted from seedling leaves of salt sensitive cultivar JW9-6 and salt tolerant cultivar JW2372 were tested under salt stress for the different durations, including 2, 12 and 72 h, using 2-D electrophoresis. Totally, 83 differentially expressed proteins were found using MALDI-TOF/TOF MS. These proteins were divided into 11 classes. The primary findings from this study are: (1) enhanced ROS scavenging capacity leads to increased salt tolerance for the shrub willow that protects redox homeostasis system from being damaged; (2) different measures, e.g., the inhibition of protein synthesis, protein folding and assembly, and enhancing protein proteolysis, were essential for shrub willow seedlings to respond to salt stress; (3) salt stress could affect the pathways of photosynthesis, carbohydrate metabolism, energy supply, and metabolism for amino acid and nitrogen. (4) JW2372 are more salt tolerant than that of cultivar JW9-6 due to overall performance of the above pathways.