Pull-down assays for plant hormone research.

Hormonal signals are transduced (and sometimes perceived) by protein-protein interactions. Understanding these interactions is therefore crucial to understanding the network of signalling components as a whole. Often, genetic analysis serves up a selection of players that may or may not interact directly to carry the signal in question and further insight inevitably leads to some sort of biochemistry. Using the example of the auxin-regulated interaction between the auxin receptor TIR1 and the Aux/IAA repressor proteins, this chapter deals with some of this biochemistry, describing a very simple assay for looking at which proteins are interacting, and if and how those interactions are regulated.