دانلود رایگان مقاله انگلیسی تاثیر تنش خشکی در تنوع برگ پروتئوم باقلا سبز (باقلا) در فلات تبت-چینگهای چین - اشپرینگر 2018

Abstract

Water scarcity is a major abiotic stress factor that strongly infuences growth, development and yield of grain legumes in arid and semi-arid area of the world. Drought stress frequently occurs during the seedling stage and fnally afects yield of faba bean (Vicia faba L.). However, the responses of plant leaf to drought have not been documented very well at the proteomic level. “Ga da dou” of the drought-tolerant faba bean cultivar was exposed to drought to examine the proteome changes of leaves. In this study, 2-week-old seedlings were subjected to water defcit by 7 days drought stress, whereas control plants were regularly irrigated. After withdrawing water, plants exposed to drought for 7 days and control plants at the same developmental stage were included in quantitative proteomic analysis using two-dimensional electrophoresis gels of proteins in combination with mass spectrometry. Over 300 proteins were detected by 2-DE, 50 diferentially expressed proteins were detected by t test and 30 proteins were successfully identifed by MALDI-TOF/TOF, in which 25 proteins were clearly downregulated and fve proteins were upregulated. The quantifed proteins were grouped into fve functional groups, mainly regulatory proteins (46.7%), energy metabolism (23.3%), cell cytoskeleton (6.7%), other functions (20%) and unknown function (3.3%). Chitinase was upregulated under drought, suggesting that it was an important part of the plant defense system, playing an important role in stress resistance. 50S ribosomal protein was upregulated under drought, suggesting its role in protecting plants against stress by re-establishing normal protein conformations. The abundance of proteins involved in protein synthesis such as chitinase, Bet protein and glutamate–glyoxylate aminotransferase was upregulated under drought stress. These proteins could play important roles in drought tolerance and contribute to the relatively stronger drought tolerance of “Ga da dou”.

Conclusions

In this study, the abundance of proteins in faba bean under drought stress conditions in Qinghai–Tibet Plateau of China was identifed at frst time. 25 proteins were clearly downregulated and fve proteins were upregulated in 30 diferentially expressed proteins. Regulatory proteins and metabolism within energy metabolism proteins hold very important positions in fve types of functional category. Under drought stress, regulatory proteins (heat shock protein 81-2) could ease of denatured protein concentration, stimulate new peptides further folds into a functional protein, assist the degradation of misfolded proteins to resist drought stress. The downregulated proteins mainly regulate the balance of stress defense, energy metabolism, cytoskeleton and oxidation, and the upregulated proteins regulate proteins folding and aggregation and photosynthesis system. The results suggest that proteins related to the cell defense pathways are modulated by overlapping signaling mechanisms, which provided information for overall understanding and engineering strategies to improve drought tolerance of faba bean in Qinghai–Tibet Plateau of China.