The Construction Of Two-dimensional Gel Electrophoresis Experimental System And The Function Analysis Of Ifferentially Expressed Proteins Tinder Drought Stress In Cotton

Xinjiang is the largest cotton-producing area in China, but it is located in the inland region,and the climate is drought and less rain,all of these seriously restrict the cotton growth. Therefore, the emergency problems of Xinjiang cotton production are that the further study of drought resistant mechanism, and then explore the essence of drought resistance, finally, breed out strong drought resistant cotton varieties. The traditional research of drought resistance mostly focused on nucleic acid level, it was very difficult to reveal the drought resistant mechanism of the cotton fundamentally. As is known to all, the protein is the executor of the life activities, which reflects all kinds of life phenomenons directly. Therefore, this study had very important significance for understanding drought resistant mechanism and then guiding the cotton drought resistant breeding, which researched the differences in protein level of the cotton under drought stress combined with the mass spectrometry and bioinformatics.Cotton seedling was used in this study, which stressed by PEG, and then studied the differentially expressed of cotton proteome under different processing conditions with the method of Two-dimensional Electrophoresis. We cut the significant different protein points,which were identified by peptide fingerprint and matched by the database.and then combined with the knowledge of bioinfonnatics,finally analysised the internal relations between these proteins and the cotton drought resistance. This study explored drought resistant mechanism of the cotton in the protein level, in order to provide some help for resistant research and breed stronge drought resistant cotton new varieties. The main results were below:1. Comparison of Phenol method, TCA/acetone method and improved TCA/acetone method, we concluded that the improved TCA/acetone method was the most suitable extraction method for the cotton leaves.2. When the lysis buffer contained7mol/L Urea,2mol/L Thiourea,4%CHAPS,80mmol/L DTT,1mmol/L PMSF,0.3%Bio-Lyte,the protein sample dissolved very well.Nitric acid silver staining method was suitable for the preparation of analysis gels,but the gels stained by Coomassie brilliant blue method was more better compatible with the mass spectrumetry. When the loading amounts of protein with600μg, and the IPG (pH4-7,24cm), a good protein pattern was obtained.3. We did MALDI-TOF-TOF/MS analysises of113significant different protein points, finally102protein points were identified successfully. Function analysis showed that:They were mainly involved in the carbohydrate metabolism, photosynthesis, cell defense, amino acidsand protein synthesis, cells processing, molecular partner and other processes.