Using peptide arrays created by the SPOT method for defining protein-protein interactions

Evaluating sites of protein-protein interactions can be an arduous task involving extensive mutagenesis work and attempts to express and purify individual proteins in sufficient quantities. Peptide mapping is a useful alternative to traditional methods as it allows rapid detection of regions and/or individual residues important for binding, and it can be readily applied to numerous proteins at once. Here we describe the use of the ResPep SL SPOT method to evaluate protein-protein binding interactions such as that between G-protein βγ subunits and SNARE proteins, identifying both regions of interest and subsequently individual residues which can then be manipulated in further biochemical assays to confirm their validity.