Tuning Hsp70 Complexes with Small Molecules

November 14, 2014

Jason E. Gestwicki

Heat shock protein 70 (Hsp70) collaborates with a large family of co-chaperones, generating a multitude of possible multi-protein complexes. It is compelling to hypothesize that each combination of an Hsp70 and its co-chaperones might be dedicated to a specific biological pathway or function. However, only a few examples of functional diversification have been reported. Towards broadening this goal, we have reconstituted specific combinations of Hsp70 and its major co-chaperones and systematically characterized the biochemical properties, stoichiometries and protein-protein affinities of these combinations. In a select number of experimental tests, some of the combinations had potent chaperone activity, while others were inactive. These results support the idea that combinations of Hsp70 and its co-chaperones may play unique roles. Finally, we have used these reconstituted complexes to screen for molecules that might target individual combinations. Progress towards developing a suite of context-specific Hsp70 agonists and antagonists will be reported.