Shuguang Yuan, H C Stephen Chan, Horst Vogel, Slawomir Filipek, Raymond C Stevens, Krzysztof Palczewski
Angewandte Chemie (International ed. in English) 2016 Aug 22Human purinergic G protein-coupled receptor P2Y1 (P2Y1 R) is activated by adenosine 5'-diphosphate (ADP) to induce platelet activation and thereby serves as an important antithrombotic drug target. Crystal structures of P2Y1 R revealed that one ligand (MRS2500) binds to the extracellular vestibule of this GPCR, whereas another (BPTU) occupies the surface between transmembrane (TM) helices TM2 and TM3. We introduced a total of 20 μs all-atom long-timescale molecular dynamic (MD) simulations to inquire why two molecules in completely different locations both serve as antagonists while ADP activates the receptor. Our results indicate that BPTU acts as an antagonist by stabilizing extracellular helix bundles leading to an increase of the lipid order, whereas MRS2500 blocks signaling by occupying the ligand binding site. Both antagonists stabilize an ionic lock within the receptor. However, binding of ADP breaks this ionic lock, forming a continuous water channel that leads to P2Y1 R activation. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.
Shuguang Yuan, H C Stephen Chan, Horst Vogel, Slawomir Filipek, Raymond C Stevens, Krzysztof Palczewski. The Molecular Mechanism of P2Y1 Receptor Activation. Angewandte Chemie (International ed. in English). 2016 Aug 22;55(35):10331-5
PMID: 27460867
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