Identification of endogenous surrogate ligands for human P2Y receptors through an in silico search.
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 alpha-helices that form an alpha-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 P2Y(1) (hP2Y(1)) 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 hP2Y(1)-receptor model using AutoDock 3.0. We selected 21 of the 30 top-ranked compounds, and by measuring intracellular Ca(2+) concentration, we identified 12 compounds that activated or blocked the hP2Y(1) receptor stably expressed in recombinant CHO cells. 5-Phosphoribosyl-1-pyrophosphate (PRPP) was found to activate the hP2Y(1) receptor with a low ED(50) value of 15 nM. The Ca(2+) assays showed it had no significant effect on P2Y(2), P2Y(6), or P2X(2) receptors, but acted as a weak agonist on the P2Y(12) receptor. This is the first study to rationally identify surrogate ligands for the P2Y-receptor family.
Hiramoto
Takeshi
T
Laboratory of Pharmcoinformatics, Department of Bioscience and Biotechnology, College of Science and Engineering, Ritsumeikan University, Kusatsu, Shiga, Japan.
Nonaka
Yosuke
Y
Inoue
Kazuko
K
Yamamoto
Takefumi
T
Omatsu-Kanbe
Mariko
M
Matsuura
Hiroshi
H
Gohda
Keigo
K
Fujita
Norihisa
N
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008024:Ligands; D018048:Receptors, Purinergic P2 / Q000378:metabolism*; D058472:Receptors, Purinergic P2Y1; D017655:Silicon Compounds / Q000737:chemistry / Q000378:metabolism*
D015415:Biomarkers; D008024:Ligands; C546382:P2RY1 protein, human; D018048:Receptors, Purinergic P2; D058472:Receptors, Purinergic P2Y1; D017655:Silicon Compounds; D002118:Calcium