Molecular chaperone that promotes the maturation, structural maintenance and proper regulation of specific target proteins involved for instance in cell cycle control and signal transduction. Undergoes a functional cycle that is linked to its ATPase activity. This cycle probably induces conformational changes in the client proteins, thereby causing their activation. Interacts dynamically with various co-chaperones that modulate its substrate recognition, ATPase cycle and chaperone function. Homodimer. Interacts with p53/TP53. Forms a complex with CDK6 and Hsp90/HSP90AB1. Interacts with UNC45A. Binding to UNC45A involves 2 UNC45A monomers per HSP90AB1 dimer. Interacts with CHORDC1 and DNAJC7. Interacts with FKBP4. Belongs to the heat shock protein 90 family. Note: This description may include information from UniProtKB.