 HSP90 is a molecular chaperone that works together with the phosphorylated CDC-37 co-chaperone to activate and fold its many client kinases. When these kinases are phosphorylated at certain regulatory sites, they can be released from HSP90's grip by the enzyme PP5. However, this process requires the kinase to first be released from HSP90's grasp, which is accomplished through a mechanism involving steric inhibition of CDC-37's ability to be defosphorylated. This mechanism was discovered using cryoelectron microscopy, which revealed the structure of HSP90, CDC-37, and the kinase CIF in complex. This structure showed that HSP90 binds to the kinase and also helps position CDC-37 so it can defosphorylate the kinase. This study provides insight into how HSP90 works with other proteins to regulate cellular processes. This article was authored by Maru Jamigaza, Carlos A. Nowatmi, Daniel Kutandin, and others. We are article.tv, links in the description below.