Evidence for Novel Action at the Cell‐Binding Site of Human Angiogenin Revealed by Heteronuclear NMR Spectroscopy, in silico and in vivo Studies

• Published in: ChemMedChem 2018-02, Vol.13 (3), p.259-269
• Main Authors: Chatzileontiadou, Demetra S. M., Tsika, Aikaterini C., Diamantopoulou, Zoi, Delbé, Jean, Badet, Josette, Courty, José, Skamnaki, Vassiliki T., Parmenopoulou, Vanessa, Komiotis, Dimitri, Hayes, Joseph M., Spyroulias, Georgios A., Leonidas, Demetres D.
• Format: Article
• Language: English
• Subjects: angiogenesis; Animals; Binding Sites; Cell Line; Cellular Biology; Chick Embryo; Chorioallantoic Membrane - blood supply; Chorioallantoic Membrane - drug effects; Computer Simulation; Humans; Life Sciences; Molecular Dynamics Simulation; Neovascularization, Physiologic - drug effects; NMR spectroscopy; Nuclear Magnetic Resonance, Biomolecular; nucleosides; Pyrimidine Nucleosides - chemistry; Ribonuclease, Pancreatic - antagonists & inhibitors; RNase; Structure-Activity Relationship; triazoles
• ISSN: 1860-7179; 1860-7187
• DOI: 10.1002/cmdc.201700688

A member of the ribonuclease A superfamily, human angiogenin (hAng) is a potent angiogenic factor. Heteronuclear NMR spectroscopy combined with induced‐fit docking revealed a dual binding mode for the most antiangiogenic compound of a series of ribofuranosyl pyrimidine nucleosides that strongly inhibit hAng's angiogenic activity in vivo. While modeling suggests the potential for simultaneous binding of the inhibitors at the active and cell‐binding sites, NMR studies indicate greater affinity for the cell‐binding site than for the active site. Additionally, molecular dynamics simulations at 100 ns confirmed the stability of binding at the cell‐binding site with the predicted protein–ligand interactions, in excellent agreement with the NMR data. This is the first time that a nucleoside inhibitor is reported to completely inhibit the angiogenic activity of hAng in vivo by exerting dual inhibitory activity on hAng, blocking both the entrance of hAng into the cell and its ribonucleolytic activity. Where inhibitors hAng out: A nucleoside is reported to disrupt the biological function of human angiogenin (hAng) both in vivo and its enzymatic activity in vitro. NMR spectroscopy revealed simultaneous binding at the cellular and active site of hAng, whereas computational modeling, in line with NMR data, highlighted the protein–ligand interactions involved.