Proteomic Analysis On Germination Of Davidia Involucrate Seeds

Dovetree is the first class national protect plant and the endemic specie of China.It is of high value to ornamental and academic study. Based on Davidia involucrata seed, our experiment compared different methods of protein extraction by testing the extracted protein content and determined the method of total proteins extraction by removing high-abundance proteins. We also compared the changes of proteomics between different period of seed stratification by iTRAQ. The results are as follows:(1) After the same sample size of 8 protein extraction programs were fixed,SDS-PAGE one-way electrophoresis was then used to find the higher efficiency method of total protein extraction.(2) The protein content of cotyledon and hypocotyl during the same period of stratification, and also the variation on protein content of hypocotyl between different periods were compared.(3) Because of large numbers of abundant proteins on the gel.The detection of less abundant proteins could not be free from disturbance. By using the method of removing high-abundance proteins, we found that PEG6000 powers was added at the volume ratio of 4% to protein extracts proteins had a better result of precipitating abundant proteins than the ratio of 5% and 6%, especially when the concentration of PEG was 12%.(4) 867 kinds of proteins of Davidia involucrata seed were identified by using iTRAQ technology. 682 kinds of proteins of differential expression were found by comparing the untreated and stratified(8 and 13 months) seeds in pairs. 300 kinds of proteins reached 2-fold change and accounted for 44% of the total identified proteins(155 kinds and 145 kinds were down-regulated and up-regulated respectively).(5) By using KEGG pathway and GO analysis on differential proteins of Davidia involucrata, we found these proteins were mainly concentrated on energy metabolism pathway and ion transport. 53 differential proteins(25 and 28 proteins were up-ragulated and down-ragulated respectively) participated in energy metabolism, 65 differential proteins(32 and 33 proteins were up-ragulated and down-ragulated respectively) participated in biosynthesis.By the results of the study show, Davidia involucrata seed dormancy behavior and changes of protein content during the germination of closely related. In this study,we identified a likely control the dormancy of specific proteins and to further study termination of Davidia involucrata seed dormancy provides new clues.