Identification And Functional Analysis Of Rice Thioredoxin OsTRXh1 Interaction Proteins

The stability of redox state in plants plays an important role in the normal physiological processes. In normal growth and development as well as under biotic and abiotic stress, the plants will generate reactive oxygen species(ROS) and this will break redox homeostasis, then the plants will start their own defense mechanisms to clear ROS and restore the redox homeostasis. As a redox active protein, Thioredoxins involved in regulating the redox homeostasis of plants. The target proteins of thioredoxin allow us to more fully understand the mechanisms of a variety of ways thioredoxin involved in. Particularly after proteomics technology had been mature, we have identified a large number of potential target proteins, preliminary analysis found that thioredoxin involved in almost all of the pathways in the cells.Previously, we analyzed the soluble apoplast proteins of rice roots by two-dimensional electrophoresis, an h-type thioredoxin(OsTRXhl), which was identified by mass spectrometry, is up-regulated under salt stress at different times. Preliminary experiments proved that OsTRXhl also had the typical redox activity and might involve in regulatory pathways of growth and development as well as stress responses. The main purpose of this project is to identify OsTRXhl target proteins and verify the interaction between OsTRXhl and target proteins so as to further elaborate the molecular mechanism of OsTRXhl.We isolated and identified target proteins using the point mutant OsTRXhlC43S though the combination of affinity chromatography and proteomics methods. In this project, a total of 238 target proteins were isolated. After bioinformatics analysis, we did a simple classification according to subcellular localization and function firstly, and then we selected 10 interested proteins as our object of study. We further validated the interaction between the 10 proteins and OsTRXhl by bimolecular fluorescence complementation technology (BiFC). So far, it turned out that RPN, HAL3, NRX, RIC1, L-APX1 and UP interacted with OsTRXhl out of the ten proteins (RPN, ADH1, HAL3, NRX, TCP1θ, pGLU, RIC1, L-APX1, UP and SO) we have identified.