GST pull-down assay - (Jan/27/2004 )

Does anyone know what GST pulldown assay is?

GST pull-down assay is a simple technique to test interaction between a tagged protein or the bait (GST, His6, biotin ...) and another protein (test protein, or prey).

The bait protein, purified from an appropriate expression system (e.g., Escherichia coli), is immobilized on a glutathione affinity gel. The bait serves as the secondary affinity support for identifying new protein partners or for confirming a previously suspected protein partner to the bait.

Prey protein can be obtained from multiple sources including recombinant purified proteins, cell lysate or in vitro transcription/translation reactions.

Protein-protein interactions can be visualized by SDS-PAGE and associated detection methods depending on the sensitivity requirements of the interacting proteins. These methods include Coomassie or silver staining, Western blotting and [35S] radioisotopic detection.