Different Proteomic Analysis Of The Peel Of ‘clapp’s Favorite’ Pear And Its Red Skin Bud Mutation

In the present study, ‘Clapp’s Favorite’ pear and its red skin bud mutation ‘Starkrimson’ pear were used as materials. The separation, identification and bioinformatics analysis of different proteins were done by the techonology of proteomics. The objectives were to find the key factors which were associated with red pear coloring from the protein level, and to provide the important information for molecular breeding of red pear. The main results were as follows:1. The total anthocyanin content of ‘Starkrimson’ pear and ‘Clapp’s Favorite’ pear by fruit bagging and re-exposure treatments were determined. The content of anthocyanin was low in both unbagged ‘Clapp’s Favorite’ pear(white) and bagged ‘Clapp’s Favorite’ pear(green). The ‘Starkrimson’ pear with 0 day, 1 day, 3days of re-exposure treatments were light pink and the contents of anthocyanin were similar to the content in ‘Clapp’s Favorite’ pears; The content of anthocyanin started increase in the 5 days, thereafter, the contents increased significantly and the fruits coloring deepened gradually in 10 days and 15 days; The content of anthocyanin was highest in unbagged ‘Starkrimson’ pear and the fruit was dark red. The result indicated that the content of anthocyanin appears a rising trend with the red color gradually deepening in pear skins.2. Through the study on total protein extraction methods(phenol method and the modified phenol method) and the sample amount(800 ug and 1000 ug), we found that using modified phenol method, the sample amount 1000 ug with 17 cm PH 4-7 IPG strips, equilibrium time 15 min could obtain good repeatability, high-quality electrophoresis map.3. The proteomic research was performed on ‘Starkrimson’ pear and ‘Clapp’s Favorite’ pear by 2-DE method. 68 spots were found and 62 proteins were confidently identified by MALDI-TOF MS analysis. The successfully identified proteins were involved in a wide range of metabolic processes and pathways, including carbohydrate metabolism, energy metabolism, protein metabolism, cellular processes, signal transduction, stress response/defense and so on.4. Subcellular localization predictions were taken on the identified protein. The results showed that 29 different proteins were located in cytoplasm, 12 different proteins were located in mitochondria, 3 different proteins were located in endoplasmic reticulum, 1 different proteins were located in plasma membrane, 1 different proteins were located in golgi, 4 different proteins were multi subcellular localization, the remaining 5 proteins could not found their subcellular localization by prediction.5. According to the functional analysis of differential proteins and real-time fluorescence quantitative analysis, we supposed that LHCII type I chlorophyll a/b binding protein(Cab, spot 43) related to photosynthesis, phosphoglycerate kinase(PGK, spot 34) related to the formation of anthocyanin precursors, CLPC protein related to protein metabolism may be associated with the fruit coloring. In addition, α-1, 4-glucan protein synthases(UPTG, spot 33) related to cellular processes and 14-3-3 protein involved in signal transduction may also have somthing to do with fruit coloring.