Analysis Of Proteomic Differences Of Beet Leaves In Response To Drought Stress

Beet is the second largest sugar crop in China.Its planting areas are mainly in northwest,north and northeast of China,Most parts of these areas belong to arid and semi-arid climate areas.Because of the limitations of regional factors such as low annual precipitation,unbalanced seasonal distribution and lack of effective irrigation conditions,Drought is still the biggest abiotic factor to restrict sugar beet planting and sustainable development in this region.Therefore,it is of great significance to clarify the drought-resistant response mechanism of sugar beet under water stress,cultivate drought-resistant sugar beet varieties and take effective drought-resistant control measures.In this experiment,drought-resistant sugar beet seedling leaves were used as materials to analyze physiological response and proteomic study of sugar beet seedlings under different drought stress by iTRAQ technology,so as to preliminarily clarify the response mechanism of sugar beet under water stress from the perspective of proteomics.The research results are as follows:1.Under drought stress,stomatal resistance increased,ABA content increased,net photosynthetic rate decreased,F0 and qN increased,Fv/Fm decreased.2.Proteomic identification revealed a total of 5531 kinds of proteins.Among them,163 differentially expressed proteins were obtained under severe water stress,including 90 up-regulated proteins and 63 down-regulated proteins,which participate in energy and protein metabolism,hormone synthesis,signal transduction and other pathways respectively.3.Through subcellular localization prediction,differential proteins are mainly distributed in chloroplasts,cytoplasm,nucleus and mitochondria,and a small amount of differential proteins are also localized in cell membranes,cell walls,endoplasmic reticulum,peroxidase bodies,vacuoles and Golgi bodies.4.163 differential proteins were successfully annotated to 63 different metabolic Pathways through pathway annotation.Among them,carbohydrate metabolism pathway,energy metabolism pathway and amino acid metabolism pathway are the most abundant,followed by biosynthesis pathway of secondary metabolites,cofactors and vitamin metabolism,and protein translation,processing and modification.Using GO and KEGG annotations,we found some important differential proteins related to drought resistance,including 13 photosynthesis-related proteins,2 ABA-related proteins,2 water stress-induced proteins and 1 biosynthesis-related protein.