Probing structural features and binding mode of 3-arylpyrimidin-2,4-diones within housefly γ-aminobutyric acid (GABA) receptor.
In order to obtain structural features of 3-arylpyrimidin-2,4-diones emerged as promising inhibitors of insect γ-aminobutyric acid (GABA) receptor, a set of ligand-/receptor-based 3D-QSAR models for 60 derivatives are generated using Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Index Analysis (CoMSIA). The statistically optimal CoMSIA model is produced with highest q(2) of 0.62, r(2) (ncv) of 0.97, and r(2) (pred) of 0.95. A minor/bulky electronegative hydrophilic polar substituent at the 1-/6-postion of the uracil ring, and bulky substituents at the 3'-, 4'- and 5'-positions of the benzene ring are beneficial for the enhanced potency of the inhibitors as revealed by the obtained 3D-contour maps. Furthermore, homology modeling, molecular dynamics (MD) simulation and molecular docking are also carried out to gain a better understanding of the probable binding modes of these inhibitors, and the results show that residues Ala-183(C), Thr-187(B), Thr-187(D) and Thr-187(E) in the second transmembrane domains of GABA receptor are responsible for the H-bonding interactions with the inhibitor. The good correlation between docking observations and 3D-QSAR analyses further proves the model reasonability in probing the structural features and the binding mode of 3-arylpyrimidin-2,4-dione derivatives within the housefly GABA receptor.
College of Veterinary Medicine, Northwest A & F University, Yangling 712100, Shaanxi, China; E-Mails:  liqinfan@yahoo.com.cn  (Q.L.);  zhanglihui200701@163.com  (L.Z.);  407147075@qq.com  (X.K.).
Qinfan
Q
Li
Lihui
L
Zhang
Zhi
Z
Ma
Xiangya
X
Kong
Fangfang
F
Wang
Hong
H
Zhang
Yonghua
Y
Wang
D000465:Algorithms; D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D018756:GABA Antagonists / Q000737:chemistry* / Q000378:metabolism; D006793:Houseflies / Q000378:metabolism*; D057927:Hydrophobic and Hydrophilic Interactions; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D021281:Quantitative Structure-Activity Relationship; D018079:Receptors, GABA / Q000737:chemistry* / Q000378:metabolism; D013941:Thymine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism
D018756:GABA Antagonists; D018079:Receptors, GABA; D013941:Thymine