Structural Basis for High-Affinity Peptide Inhibition of Human Pin1

• Published in: ACS chemical biology Vol. 2; no. 5; pp. 320 - 328
• Main Authors: Zhang, Yan, Daum, Sebastian, Wildemann, Dirk, Zhou, Xiao Zhen, Verdecia, Mark A, Bowman, Marianne E, Lücke, Christian, Hunter, Tony, Lu, Kun-Ping, Fischer, Gunter, Noel, Joseph P
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 01.05.2007
• Subjects: Binding Sites; Crystallography, X-Ray; Drug Design; Enzyme Inhibitors - chemical synthesis; Enzyme Inhibitors - chemistry; Enzyme Inhibitors - pharmacology; Humans; Isomerism; Ligands; Models, Molecular; NIMA-Interacting Peptidylprolyl Isomerase; Oligopeptides - chemical synthesis; Oligopeptides - chemistry; Oligopeptides - pharmacology; Peptide Library; Peptidylprolyl Isomerase - antagonists & inhibitors; Peptidylprolyl Isomerase - chemistry; Protein Binding; Structure-Activity Relationship; Substrate Specificity
• ISSN: 1554-8929; 1554-8937
• DOI: 10.1021/cb7000044

Human Pin1 is a key regulator of cell-cycle progression and plays growth-promoting roles in human cancers. High-affinity inhibitors of Pin1 may provide a unique opportunity for disrupting oncogenic pathways. Here we report two high-resolution X-ray crystal structures of human Pin1 bound to non-natural peptide inhibitors. The structures of the bound high-affinity peptides identify a type-I β-turn conformation for Pin1 prolyl peptide isomerase domain–peptide binding and an extensive molecular interface for high-affinity recognition. Moreover, these structures suggest chemical elements that may further improve the affinity and pharmacological properties of future peptide-based Pin inhibitors. Finally, an intramolecular hydrogen bond observed in both peptide complexes mimics the cyclic conformation of FK506 and rapamycin. Both FK506 and rapamycin are clinically important inhibitors of other peptidyl-prolyl cis-trans isomerases. This comparative discovery suggests that a cyclic peptide polyketide bridge, like that found in FK506 and rapamycin or a similar linkage, may significantly improve the binding affinity of structure-based Pin1 inhibitors.