Yeast two-hybrid approaches to dissecting the plant defense response

We describe a reliable GAL4-based yeast two-hybrid system for identifying and isolating clones encoding proteins interacting with a protein of interest. This two-hybrid system gives extremely low background and few false-positive clones, making it ideal for library screening purposes. We have successfully used it not only to isolate Arabidopsis NPR1-interactors from rice but also to pull out the rice NPR1 ortholog using one of the interactors as bait.