Download MendeleyMolecular Recognition of the Hybrid-2 Human Telomeric G-Quadruplex by Epiberberine: Insights into Conversion of Telomeric G-Quadruplex Structures.
Lin, C., Wu, G., Wang, K., Onel, B., Sakai, S., Shao, Y., Yang, D.(2018) Angew Chem Int Ed Engl 57: 10888-10893
- PubMed: 29888501
- DOI: https://doi.org/10.1002/anie.201804667
- Primary Citation of Related Structures:
6CCW - PubMed Abstract:
Human telomeres can form DNA G-quadruplex (G4), an attractive target for anticancer drugs. Human telomeric G4s bear inherent structure polymorphism, challenging for understanding specific recognition by ligands or proteins. Protoberberines are medicinal natural-products known to stabilize telomeric G4s and inhibit telomerase. Here we report epiberberine (EPI) specifically recognizes the hybrid-2 telomeric G4 predominant in physiologically relevant K + solution and converts other telomeric G4 forms to hybrid-2, the first such example reported. Our NMR structure in K + solution shows EPI binding induces extensive rearrangement of the previously disordered 5'-flanking and loop segments to form an unprecedented four-layer binding pocket specific to the hybrid-2 telomeric G4; EPI recruits the (-1) adenine to form a "quasi-triad" intercalated between the external tetrad and a T:T:A triad, capped by a T:T base pair. Our study provides structural basis for small-molecule drug design targeting the human telomeric G4.
Organizational Affiliation:
Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue Center for Cancer Research, Purdue University, West Lafayette, IN, 47906, USA.
