Proteomic Analysis On Leaf And Grain In Different Nitrogen Treatments Of The Rice Liangyoupeijiu

Proteomics was used as a tool to study changes in leaf and grain proteome at different Nitrogen treatments during the late growth stage of liangyoupeijiu which is the super cross rice,and then identified and analyzed the biological function of these differential proteins,attempted to discuss the molecular mechanism from Nitrogen on leaf and grain during grain filling periods of the cross rice,and clarify the molecular mechanism of the weak grain lack of filling and poor adequacy preliminarily.The research set different Nitrogen treatments during the whole rice growth period (half of normal nitrogen, normal nitrogen and doubleness of normal Nitrogen) and total leaf proteins of different treatments were extracted at 0 days,25 days after anthesis..By two-dimensional gel electrophoresis(2-DE) and image analysis,it was found that 17 leaf proteins expressed differentially in the three Nitrogen treatments,and 16 of them were identified by MALDI-TOF-TOF/MS and database searching.According to their function,those proteins were divided into these categories: about plant photosynthesis(the number was 6),they were ribulose-1,5-bisphosphate carboxylase activase, Carbonic Anhydrase, rubisco large subunit, photosystem I subunit VII,Rieske Fe—S protein,and Cytb6/f;about plant energy metabolic pathways(the number was 2)they were putative chloroplast phosphoglycerate kinase and Nucleoside diphosphate kinase I;about radical Scavenging(the number was 3)they were putative superoxide dismutase [Cu-Zn], Ascorbate peroxidase,and Peroxiredoxin (PRX) family;about protein synthesis , storage and protein-protein interaction (the number was 3)they were Putative chloroplast ribosomal protein L1, Cupin family and Ankyrin repeat domain protein;about Nitrogen assimilation(the number was 1),that was Glutamine synthetase , and others(the number was 1) that was No.Os07g0212200(.Speculate for the coenzyme binding protein with catalytic activity).Total strong and weak grain proteins of different treatments were extracted respectively 25 days after anthesis. It was found that 10 weak grain proteins expressed differentially in the three Nitrogen treatments and 9 were identified; it was found that 5 strong grain proteins expressed differentially in the three Nitrogen treatments and 4 were identified.By analysis of the identification results of the different leaf proteins,it was found that proteins about plant photosynthesis had the largest proportion and their expressional quantity were large,which showed Nitrogen affected and regulated photosynthesis by its impact on activating the photosynthetic enzyme,activating CO₂,PS unit and electronic transfer chain. Nitrogen also impacted energy synthesis,the formation and scavenging synstem of oxygen free radicals in plants,and regulated producing energy and scavenging oxygen free radicals as physiological function.Another,Nitrogen affected protein synthesis,storage and interaction..Duringmy research,a protein about Nitrogen assimilation——Glutamine synthetase was identified.Andwith the increasing of Nitrogen, its expressional quantity increased,which showed Nitrogen promoted the synthesis of GS which about Nitrogen metabolism, and affected Nitrogen assimilation and metabolism.By analysis of the identification results of the different weak grain proteins, it was found that the expressional quantity of ATP synthase, Argininosuccinate synthase, succinyl-CoA synthetase beta subunit, IAA amidohydrolase, malate dehydrogenase , dihydrolipoamide acetyltransferase and Ran GTPase were increased at doubleness Nitrogen treatment .And these increased proteins of the weak grain focused in these areas :(1)Proteins about synthesis energy;(2) Accelerate TCA cycle of producing energy;(3) Promote growth and cell division in the release of IAA.The results showed energy and growth were the theme of weak grain filling. alpha-crystallin-type heat shock proteins had stable expression at normal and doubleness Nitrogen treatments as molecular chaperone regulating graining filling.By analysis of the identification results of the different strong grain proteins,it was found with the increase of the Nitrogen, the expressional quantity of Glutelin as storage protein increased, the expressional quantity of Ricin B lectin and Fructose-bisphosphate aldolase cytoplasmic isozyme were the most at normal Nitrogen treatment compared with the high and the low Nitrogen treatments. The expressional quantity of glucose-1-phosphate adenylyltransferase which was about the formation of starch was decreased at doubleness Nitrogen treatments instead compared with the normal Nitrogen .Those changes of expressional quantity showed the strong and weak grain had clear distinctions in metabolic characteristics and center at different filling stages. Then Nitrogen affected the storage of related protein and carbohydrate metabolism and respiration regulation of strong grain, and the high Nitrogen level of this phase was not positive factor for starch synthesis of strong grain.Nitrogen is the life element in plant, and Nitrogen nutrition plays an important role in impacting and regulating plant life activity. Reasonable use of the Nitrogen nutrition has an important role for raising the flag leaf photosynthetic , enhancing supply capacity of source and the ability of preventing aging. From the results , the energy and hormone level is one of the main factors restricting development and filling of weak grain. Adequate supply of Nitrogen has great significance for weak grain filling at the late stage. Although the impact for strong grain filling is not significant compared with weak grain, adequate and normal level of Nitrogen also has an important role in cumulating storage material and carbohydrate metabolism .