The Plasmodesmata Mediated Transport Under Hydrogen Peroxide Stress

Hydrogen peroxide is one of key players in the regulation of plant development, stress reponses, and programmed cell death. Recently, it is seen as a second messenger in the progress of plant fighting against abiotic and biotic stress, but the molecular mechanism of hydrogen peroxide mediated stress resitence is unclear. In recent years of study, there is evdience showing that a plasmodesmata mediated macromolecular transport pathway exsits in the plant cell. Some transcription factors can move through this way to adjacent cell and play an important role in the development. In addition, many plant virues can take advantage of this pathway to achieve the goal of infecting the plant. Unfortunately, the pecise mechsim of this pathway is still unknown. Moreover, more and more experiments suggest that there is not only one pathway but sveral ones exsiting in the plant cell. All these above suggest that we are far way from elucidating this precise macromolecular transport pathway.In our experiments, we use the PSUC2-GFP transgenic Arabidopsis thaliana as a tool to study the influence of hydrogen peroxide stress on the range of the GFP diffusion in the root. As the result showing, hydrogen peroxide stress can constrict the diffusion of GFP compared with the control of PSUC2-GFP siblings. The result of RT-PCR also demonstrates that the expression level of genes involved in the intracellular and intercellular movement have changed remarkably. TMV MP is the best characterized non-cell-autonomous protein and there are many experiments showing that some host factors can interact with the MP to facilitate the intracellular and intercellular movement. Whether the host factor are still helpful in the endogenous proteins non cell autonomous transport is unknown. We use BiFC technology in the Agrobacterium-mediated transient expression system to test the possibility of the interaction between transcription factors and these host factors. Some useful results have been obtained from the BiFC experiments and the non-cell-autonomous transcription factors can also interact with some host factors that has been identified to associated with TMV MP.