The Identification And Analysis Of Heat Induced Proteins In Hight-Temperature Resources Of Rice

With the development of industriation, the global warming will be irreversible. It have a direct impact on the growth, yield and quality of crop. Rice is the most important food crop. It is important to study the basis of rice genetic physiological under the climate warming conditions for the evaluation of high-temperature resources in rice varieties and guide high-temperature breeding and rice production. At present, the evaluation and selection of high-temperature resources and breeding generations and the genetic research use the fecundity under the natural high-temperature conditions in anthesis as the evaluative index. However, the difference between the rice groups and genetic resources and the variance of the physiological basis of varieties and the diversform limited factors of fecundity made it difficult to obtain the objective results. Therefore it is possible to form a evaluation method to detect the heat tolerance of rice resources in the seedling or the vegetative growth stage to find closely related to the different indicators of internal temperature physiological responses which have relatively uniform growth and physiological state. This study unite the heat physiological performance in seedling and the seed setting rate situation in anthesis to evaluate the heat tolerance in different rice resources. We choose there varieties which have different heat resistance to the identification analysis of the high-temperature express proteins in rice leaves to work out the laboratory identification method of heat-resistant species in heat induced proteins in seedling stage.1. Study on the heat physiological basis of seedling and investigation of the high-temperature seed setting rate in flowering stageWe treat six rice cultivars that respectively is N22,ShuHui 527,TeXianZhan,MianHui725, Gui 99 and 9311 with different temperatures and analysis the physiological indicators which are content of praline and MDA in leaf,content of MDA and hydrogen peroxide in root,electrical conductivity and the root's cytoplasmic integrity. The results showed that the major impact of high temperature happened in leaves, different varieties have different sensitive to high-temperature treatment however there is no significant correlation between the indexes.The result of seedling growth and livability under different heat treatment condition showed that in 4 leaf stage,47℃treatment for 2 days can identify the heat tolerances between different cultivars. Heat resistance in descending order is N22> Gui 99>9311>ShuHui 527>MianHui 725> TeXianZhan. Livability have related with praline content in leaves and other physiological indicators but haven't the significant linear relationship.The seed setting rate after high-temperature treatment in flowering stage in descending order is N22> Gui 99> ShuHui 527> 9311> TeXianZhan> MianHui 725.This result is consistent with the temperature resistance at seedling stage.2. Analysis of heat express proteins in rice leaf by two-dimensional gel electrophoresis methodWe select the distinct difference heat tolerance cultivars as the differential expression proteins materials under high-temperature. Using the improved two-dimensional electrophoresis method and selecting the differential expression proteins by mass spectrometry to obtain the different protein expression profile under different temperature in rice leaves of different cultivars.We totally have 23 different expression proteins of which 13 protein are successfully identificated by mass spectrometry. In these 13 proteins, N22 have 5 proteins, TeXianZhan and ShuHui 527 respectively have 4 proteins. We classed the proteins by their functional which belonged to Rubisco binding protein, Germin-like 1 protein,heat shock proteins and regulated protein EF-Tu. Rubisco binding proteins are up-express in N22 and ShuHui 527 under high-temperature but down-express in TeXianZhan;HSP70 and HSP 20 induced express in N22 under heat treatment. Germin-like 1 protein down expressed in all varieties under heat treatment but the expression level in TeXianZhan is significant.We compared the expression of several target proteins under 42℃,45℃and 47℃vertical temperature gradient treatment and found that:Rubisco subunit binding-protein alpha subunit (F20) and Rubisco subunit binding-protein beta subunit (F21) are both first increased then decreased, the highest expression is 45℃and has significantly decreased at 47℃.It may be due to extreme stress temperature is 47℃and many leaves have been wilting and the photosynthetic system is basically in a collapse state, it significantly reduced the protein activity; The expression of Germin-like 1 protein (G3) is the trend of first increased then decreased and finally increased; The expression of EF-Tu protein (G9) is first increasing and decreased at 47℃.The above different expression proteins may be as the high temperature related proteins at the seedling stage to identified the heat tolerance of rice varieties. This study provides a basis data for the high-temperature depth study of genetic physiological mechanisms.