Identification of Endogenous Surrogate Ligands for Human P2Y Receptors Through an In Silico Search

• Published in: Journal of Pharmacological Sciences Vol. 95; no. 1; pp. 81 - 93
• Main Authors: Hiramoto, Takeshi, Nonaka, Yosuke, Inoue, Kazuko, Yamamoto, Takefumi, Omatsu-Kanbe, Mariko, Matsuura, Hiroshi, Gohda, Keigo, Fujita, Norihisa
• Format: Journal Article
• Language: English; Japanese
• Published: Japan Elsevier B.V 2004; The Japanese Pharmacological Society; Elsevier
• Subjects: 5-phosphoribosyl-1-pyrophosphate; Animals; AutoDock; Biomarkers - metabolism; Calcium - metabolism; CHO Cells; Cricetinae; Dose-Response Relationship, Drug; G protein-coupled receptor; Humans; in silico screening; Ligands; P2Y1 receptor; Receptors, Purinergic P2 - metabolism; Receptors, Purinergic P2Y1; Silicon Compounds - chemistry; Silicon Compounds - metabolism; G protein-coupled receptor; P2Y1 receptor; in silico screening; 5-phosphoribosyl-1-pyrophosphate; AutoDock
• ISSN: 1347-8613; 1347-8648
• DOI: 10.1254/jphs.95.81

G protein-coupled receptors (GPCRs) are distributed widely throughout the human body, and nearly 50% of current medicines act on a GPCR. GPCRs are considered to consist of seven transmembrane α-helices that form an α-helical bundle in which agonists and antagonists bind. A 3D structure of the target GPCR is indispensable for designing novel medicines acting on a GPCR. We have previously constructed the 3D structure of human P2Y1 (hP2Y1) receptor, a GPCR, by homology modeling with the 3D structure of bovine rhodopsin as a template. In the present study, we have employed an in silico screening for compounds that could bind to the hP2Y1-receptor model using AutoDock 3.0. We selected 21 of the 30 top-ranked compounds, and by measuring intracellular Ca2+ concentration, we identified 12 compounds that activated or blocked the hP2Y1 receptor stably expressed in recombinant CHO cells. 5-Phosphoribosyl-1-pyrophosphate (PRPP) was found to activate the hP2Y1 receptor with a low ED50 value of 15 nM. The Ca2+ assays showed it had no significant effect on P2Y2, P2Y6, or P2X2 receptors, but acted as a weak agonist on the P2Y12 receptor. This is the first study to rationally identify surrogate ligands for the P2Y-receptor family.