Tools to Investigate ROS Sensitive Signalling Proteins

The thiols groups of cysteine residues on proteins are attractive oxidative targets for modification by reactive oxygen species, such as hydrogen peroxide (H2 O2 ). Such modification can lead to important cellular signaling processes that ultimately result in modification of physiology of the organism. To identify such proteins that are amenable to oxidative modification, different methods can be used. Here, two such approaches are described: one being the use of fluorescent thiol derivatives, and the second being the use of genetic mutants that are mutated in thiol residues. Using the model plant Arabidopsis thaliana , cell cultures, and whole plants, we describe these tools to help the reader understand the function of such thiol modification on plant responses.