The Hsp90 Chaperone Machinery

Hsp90 was originally identified as one of several conserved heat shock proteins. Like the other major classes of heat shock proteins, Hsp90 exhibits general protective chaperone properties, such as preventing the unspecific aggregation of non-native proteins (1). However, Hsp90 seems to be more selective than the other promiscuous general chaperones, as it preferentially interacts with a specific subset of the proteome (2). Another specific feature of Hsp90 is its regulatory role of inducing conformational changes in folded, native-like substrate proteins that lead to their activation or stabilization (3).