Study Of Comparative Proteomics On Laticifer Differentiation In Hevea Brasiliensis

Laticifer is specific for the biosynthesis and storage of natural rubber in rubber tree (Hevea brasiliensis Muell. Arg.). The laticifer located in the secondary phloem of trunk is closely related to the commercial production of natural rubber. So, the number of laticifer line has a significantly positive correlation to natural rubber yield and thus is an important parameter for yield breeding of rubber tree. Investigation of laticifer differentiation will aid to reveal the mechanism for vascular cambium differentiation, a major theoretical project in the field of botany, especially forestry as well as establish techniques for early prediction for the potential of secondary laticifer differentiation. The techniques are practically significant for directed genetic improvement of yield property and raising breeding efficiency. Lack of experimental system limits the progress in the study field of laticifer differentiation. By using the experimental system for laticifer differentiation induced by coronatine together with the comparative proteomics, this paper set up the differentially expressed protein profiles of vascular cambia. Differential protein spots of111and130were detected in the protein profiles of vascular cambium samples2and3days after treatment with coronatine. Of which,26proteins were successfully identified by MOLDI-TOF MS and MOLDI-TOF/TOF MS. The function of these proteins involved in sugar and energy metabolism, stress and defense, lignin biosynthesis, changes in dynamic cell skeleton, protein fold and degradation and signal transduction. Among the identified proteins, hot-shock proteins,14-3-3proteins and R20protein, a member of bHLH transcriptional factor family may be positive regulator while ascorbate peroxidase may be a negative regulator for laticifer differentiation. The results lay a good foundation for further investigation on the molecular mechanism for laticifer differentiation.