Protein-bait interactions, display libraries featured in Cold Spring Harbor Protocols

COLD SPRING HARBOR, N.Y. (Mon., Mar. 1, 2010) -- The use of recombinant proteins, antibodies, small molecules, or nucleic acids as affinity reagents is a simple yet powerful strategy to study the protein/bait interactions that drive biological processes. Analysis via mass spectrometry rather than western blotting extends the identification of interactors, often allowing detection of thousands of proteins from complex mixtures. But this increased sensitivity can lead to problems distinguishing specific interactions from background noise. In the March issue of Cold Spring Harbor Protocols (http://www.cshprotocols.org/TOCs/toc3_10.dtl), Shao-En Ong from the Broad Institute of MIT and Harvard (http://www.broadinstitute.org/proteomics/team.html) presents "Unbiased Identification of Protein-Bait Interactions Using Biochemical Enrichment and Quantitative Proteomics." This method uses quantitative proteomics approaches to compare enrichment with the bait of interest against samples using control baits to allow sensitive detection and discrimination of specific protein/bait interactions. As one of March's featured articles, it is freely available on the journal's website (http://cshprotocols.cshlp.org/cgi/content/full/2010/3/pdb.prot5400). The baculovirus expression vector system has been widely used to produce proteins originating from both prokaryotic and eukaryotic sources. It offers easy cloning techniques and abundant viral propagation, and since it is based on an insect cell environment, it provides eukaryotic posttranslational modification machinery. Surface modifications of the viral capsid enable specific targeting. Such modifications can be used to enhance viral binding and entry to a wide variety of both dividing and nondividing mammalian cells, as well as to produce antibodies against the displayed antigen. In addition, the technology should enable modifications of intracellular behavior, i.e., trafficking of recombinant "nanoparticles," a highly relevant feature for studies of targeted gene or protein delivery. In the March issue of Cold Spring Harbor Protocols (http://www.cshprotocols.org/TOCs/toc3_10.dtl), Christian Oker-Blom and colleagues (http://www.jyu.fi/bio/bit/tutkimus_files/research.html) provide a suite of articles detailing the use of baculovirus-based display and gene delivery systems. Their protocol for "Creation of Baculovirus Display Libraries" is featured, and is freely available on the journal's website (http://cshprotocols.cshlp.org/cgi/content/full/2010/3/pdb.prot5393).

Source: Cold Spring Harbor Laboratory