Hsp90 co-chaperone Cdc37 is a protein that in humans is encoded by the CDC37 gene. The protein encoded by this gene is highly similar to Cdc 37, a cell division cycle control protein of Saccharomyces cerevisiae. This protein is a molecular chaperone with specific function in cell signal transduction. It has been shown to form complex with Hsp90 and a variety of protein kinases including CDK4, CDK6, SRC, RAF1, MOK, as well as eIF-2 alpha kinases. It is thought to play a critical role in directing Hsp90 to its target kinases.