Analyses on Protein SDS-PAGE Applied to Some Woody Plants

The techniques of SDS-PAGE and Brilliant Blue and Commassie Dye were used to measure the protein contents determine and composition of vegetative storage proteins in the young leaves and the cortexes of one-year-old branches of Populus deltoids×P.euramericana,Liriodendron chinense×L.tulipifera and Ginkgo biloba.The following results were obtained: The highest content of proteins in leaves of Populus deltoids×P.euramericana and Liriodendron chinense×L.tulipifera appeared in late April,while in early May for Ginkgo biloba.The protein content in the cortex of Populus deltoids×P.euramericana decreased obviously along with time in the growing season,whereas increased in late April and then decreased in early May for both Liriodendron chinense×L.tulipifera and Ginkgo biloba.Based on the SDS-PAGE bands,it was found that the molecular weight(MW) of proteins commonly contained in the leaves of these tree species varied from 78 KD to 13 KD.The proteins with 50 KD,32 KD and 23 KD MW in the leaves of Populus deltoids×P.euramericana,proteins with 23 KD,19 KD,17 KD and 16 KD MW in the leaves of Liriodendron chinense×L.tulipifera and the proteins with 59 KD,35 KD,16 KD,14 KD and 13 KD MW contained in leaves of Ginkgo biloba changed obviously in the growth process.The molecular weight of proteins commonly contained in the cortex of these tree species varied from 58 KD to 16 KD.The proteins with 49 KD,26 KD,21 KD,15 KD and 14 KD MW in the cortex tissue of Populus deltoids×P.euramericana,proteins with 70 KD and 22 KD MW in the cortex of Liriodendron chinense×L.tulipifera and the proteins with 58 KD,29 KD,24 KD and 23 KD MW contained in cortex of Ginkgo biloba experienced significant change during the growth process.