Different Temperature Processing Of Temperature Sensitive Genic Male Sterile Rice Widely Accounted For 63s Expression Of Fertility And The Impact Of The Proteome

The rice fertility is affected by temperature and light during reproductive stage. At present, we know little about the mechanisms of temperature- and/or light-regulated fertility conversion. In present study, we investigated the changes of proteome of rice spikelet during transition of fertility using a thermo-sensitive genic male sterile rice variety, Guangzhan 63s, and tried to explore possible proteins that regulated fertility transition of rice. the main results are as follows:1. As compared with rice plants treated with high temperature (more than 26℃) during thermo-sensitive stage. Low temperature treatment (22℃) significantly increased the fertility and as high as 25.7% feritily was observed.2. In order to isolate efficiently whole proteins of rice spikelets, we firstly established and optimized the technique platform of two-dimensional electrophoresis (2-DE) for rice spikelet proteomic analysis, that is, for the first dimentional electrophoresis, the pre-cast immobilized linear pH gradient was 4-7 and the length of dry gel strips 18cm, the optimal loading amount of protein sample was 200μg for silver stain. The IPG dry strips were rehydrated for 12hr before loading protein sample. The isoelectric focusing conditions were 500V electric voltage for 1hr, 1000v for another 1hr, then gradually increased to 8000v duirng 3hr period, and kept 8000v for another 2.5hr. the gel concentration of the second dimendional elctrophoresis was 12.5%. Under these conditions, we obtained satified 2-DE map with a better repetition.3. In a 24×18 cm 2-DE gel, as many as 800 proteins had been detected. PDQuest 7.4 software analysis on protein expression profile in 2-DE gels showed that 147 differentially expressed proteins were identified between two temperature treatments. Of which 14 proteins were further characterized by MALDI-TOF-MS. Peptide fingerprint analysis combined with protein database searching indicated that proteins which were low temperature-up-regulated (more than 3-fold expression) were Enolase (2-phosphoglycerate dehydratase), triosephosphate isomerase, mitochondrial F1-ATPase. Histone H2B is specially expressed on mother pollen cells under fertile temperature, but disappeared under sterile temperature. The up-ragulated proteins on meiosis cells under fertile temperature were Caffeoyl-CoA O-methyltransferase1, Histone H2B, Caffeic acid 3-O-methyltransferase, protein phosphatase 2A regulatory subunit A, catalytic/ fumarylacetoacetase, putative aminopeptidase, putative transketolase,α-1,4-glucan-protein synthase. The Core histone H2A/H2B/H3/H4 family protein is only occurred on meiosis cells under fertile temperature. Whileas the expression of translation factor, Elongation factor G, III and V was stimulated in meiosis cells under fertile temperature.