6olx

Publication Abstract from PubMed

Hsp90alpha and Hsp90beta are implicated in a number of cancers and neurodegenerative disorders but the lack of selective pharmacological probes confounds efforts to identify their individual roles. Here, we analyzed the binding of an Hsp90alpha-selective PU compound, PU-11-trans, to the two cytosolic paralogs. We determined the co-crystal structures of Hsp90alpha and Hsp90beta bound to PU-11-trans, as well as the structure of the apo Hsp90beta NTD. The two inhibitor-bound structures reveal that Ser52, a nonconserved residue in the ATP binding pocket in Hsp90alpha, provides additional stability to PU-11-trans through a water-mediated hydrogen-bonding network. Mutation of Ser52 to alanine, as found in Hsp90beta, alters the dissociation constant of Hsp90alpha for PU-11-trans to match that of Hsp90beta. Our results provide a structural explanation for the binding preference of PU inhibitors for Hsp90alpha and demonstrate that the single nonconserved residue in the ATP-binding pocket may be exploited for alpha/beta selectivity.

Structures of Hsp90alpha and Hsp90beta bound to a purine-scaffold inhibitor reveal an exploitable residue for drug selectivity.,Huck JD, Que NLS, Sharma S, Taldone T, Chiosis G, Gewirth DT Proteins. 2019 May 29. doi: 10.1002/prot.25750. PMID:31141217^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.