Two-dimensional Electrophoresis Analysis Of Leaf Proteins Related To Development Of Liriodendron

Some improvement adapting to the analysis of the proteins of woody plant in ISO-DALT was made and the results were as follows:First, dry powder made by trichloroacetic acid and acetone was the better method in all of four disposal methods of leaf. Second, in this modified IEF protocol, a hermetic isoelectrofocusing system was set up to inhibit CO2 absorption and the cathode drift was also restrained. Furthermore, the right equilibrium time was 25 to 30 minutes and the method measuring pH grads by marker was better than that by marinating. In conclusion, all the patterns of ISO-DALT showed that the differentiation powder of the modified IEF protocol was improved greatly to meet the needs of ordinary biochemistry labs.The modified method was applied to analyze the leaf proteins related to development of Liriodendron. It was found that abundant protein spots of leaf were visualized in 2-DE gel and most of them kept the same. Their isoelectric point were found to lie between 3.2 and 7.9,and most of them were in the range of 3.8-7.0.Their molecular weights were from 12.7 to 101.8 kD, and most of them were in the range of 13.5 ~ 82 kD. Most of protein spots expressed stably in the different development of leaf, but some of them were differential.(56.5kD, pI3.6) and (28kD, pD.3) appearing at rapid enlarging stage of leaf had consanguineous relationship with development stage. (39.9kD, pI5.0) , (39.9kD, pI5.12) , (38.5kD, pI5.0) and ( 38.5kD, pI5.12) disappeared gradually from rapid enlarging stage to mature stage.2-DE gel of mature leaf had evident variety from May to June, just as the variety of etiolation stage. The increase of richness of (18.6 kD, pI4.73 ), (20.1 kD, pI5.90 ), (13.7 kD, pD.80) , (13.7 kD, pI4.09) and (13.7 kD, pI4.37) which might have an important effect on proteins' turnover had close to the decline of the richness of (53 kD, pI5.95 ) .The protein spot (24.5 kD, pI6.30) which had close relationship with etiolation stage should be the specific spot of etiolation stage of leaf.