Large-scale functional analysis using peptide or protein arrays

The array format for analyzing peptide and protein function offers an attra ctive experimental alternative to traditional library screens. Powerful new approaches have recently been described, ranging from synthetic peptide ar rays to whole proteins expressed in living cells. Comprehensive sets of pur ified peptides and proteins permit high-throughput screening for discrete b iochemical properties, whereas formats involving living cells facilitate la rge-scale genetic screening for novel biological activities. In the past ye ar, three major genome-scale studies using yeast as a model organism have i nvestigated different aspects of protein function, including biochemical ac tivities, gene disruption phenotypes, and protein-protein interactions. Suc h studies show that protein arrays can be used to examine in parallel the f unctions of thousands of proteins previously known only by their DNA sequen ce.