Study On Differential Protein Expression Of Immature Vegetable Soybean During Low-temperature Storage

Vegetable soybean has exuberant metabolism,easily aging and spoilage after harvest.At present,low temperature often is used for preservation treatment,low-temperature storage can reduce the activity of enzymes associated with the metabolism and inhibite the metabolic rate of vegetable soybean,slowing aging and maintaining the quality of vegetable soybean.In this paper,the experimental material was vegetable soybean,by comparing and optimizing related technical parameters which impacted two-dimensional electrophoresis of vegetable soybean grain protein,this paper established two-dimensional electrophoresis technology of vegetable soybean protein,studied expression profiles of differential protein of vegetable soybean during low-temperature storage,and analyzed function and role of differential protein,achieving a scientific basis that low temperature can delay the aging of vegetable soybean.The main results of this study are as follows:1.It was found that the TCA-acetone had high extraction efficiency and clear and much more spots in 2-DE map by comparing and analyzing three different extraction methods of protein,including acetone precipitation,TCA-acetone precipitation and phenol extraction.Increasing the program of the low voltage and prolonging the duration of the low voltage could promote swimming out of salt ions,improving the effect of IEF;and coomassie brilliant blue staining five steps method was used which had better effect of dyeing.The two-dimensional electrophoresis technology was established for the protein separation of vegetable soybean,which had high resolution and was suitable for research further.2.400?800 protein spots were achieved and 116 differentially expressed protein spots were found by studying 2-DE map of vegetable soybean soluble protein from different storage temperature and time by two-dimensional electrophoresis technology.Proteins abundance changes of vegetable soybean which were storaged 1 d and 7 d under different temperature and 30 d and 60 d under 1? which had 22 selected protein spots from different expression proteins respectively were compared,it was found that vegetable soybean had 6 and 3 proteins which were up-regulated and down-regulated respectively for 1 d during different storage temperature,and 5 and 3 proteins which were up-regulated and down-regulated for 7 d;within 60 d under 1 ? storage,vegetable soybean had 1 and 7 proteins which were up-regulated and down-regulated respectively with the extension of low-temperature storage time.Through up-regulated and down-regulated expression of the protein,vegetable soybean can be in response to low-temperature stress during low-temperature storage.3.78 differential proteins were identified by mass spectrometry identification of differential proteins and related database search.The nature of differential protein was classified by reading literature,which showed the proteins associated with stress resistance and involved in defense-related proteins were much more,also including some storage protein,seed germination and mature related proteins and cell growth and division related protein.It also was found that the expression of proteins associated with stress resistance and proteins involved in defense increase with the extension of low-temperature storage time,such as Lea protein,formate-tetrahydrofolate ligase-like,kunitz-type trypsin inhibitor KTI1-like,which could protect vegetable soybean from chilling injury and maintain grain quality during low-temperature storage.