title: Insights into the binding of Phenyltiocarbamide (PTC) agonist to its target human TAS2R38 bitter receptor.
abstract: Humans' bitter taste perception is mediated by the hTAS2R subfamily of the G protein-coupled membrane receptors (GPCRs). Structural information on these receptors is currently limited. Here we identify residues involved in the binding of phenylthiocarbamide (PTC) and in receptor activation in one of the most widely studied hTAS2Rs (hTAS2R38) by means of structural bioinformatics and molecular docking. The predictions are validated by site-directed mutagenesis experiments that involve specific residues located in the putative binding site and trans-membrane (TM) helices 6 and 7 putatively involved in receptor activation. Based on our measurements, we suggest that (i) residue N103 participates actively in PTC binding, in line with previous computational studies. (ii) W99, M100 and S259 contribute to define the size and shape of the binding cavity. (iii) W99 and M100, along with F255 and V296, play a key role for receptor activation, providing insights on bitter taste receptor activation not emerging from the previously reported computational models.
authors.affiliation: Statistical and Biological Physics, International School for Advanced Studies and DEMOCRITOS Modeling, Center for Research in Atomistic Simulations, Trieste, Italy.
authors.forename: Xevi
authors.initials: X
authors.lastname: Biarnés
authors.forename: Alessandro
authors.initials: A
authors.lastname: Marchiori
authors.forename: Alejandro
authors.initials: A
authors.lastname: Giorgetti
authors.forename: Carmela
authors.initials: C
authors.lastname: Lanzara
authors.forename: Paolo
authors.initials: P
authors.lastname: Gasparini
authors.forename: Paolo
authors.initials: P
authors.lastname: Carloni
authors.forename: Stephan
authors.initials: S
authors.lastname: Born
authors.forename: Anne
authors.initials: A
authors.lastname: Brockhoff
authors.forename: Maik
authors.initials: M
authors.lastname: Behrens
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Meyerhof
mesh_terms: D000595:Amino Acid Sequence; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D019295:Computational Biology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010670:Phenylthiourea / Q000378:metabolism* / Q000494:pharmacology*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D043562:Receptors, G-Protein-Coupled / Q000819:agonists* / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000098706:Taste Receptors, Type 2
chemical_list: D008024:Ligands; D043562:Receptors, G-Protein-Coupled; D000098706:Taste Receptors, Type 2; D010670:Phenylthiourea; D002118:Calcium
references.citation: Bioinformatics. 2005 Apr 1;21(7):951-60
references.pmid: 15531603
references.citation: Biophys J. 1992 Apr;62(1):107-9
references.pmid: 1600090
references.citation: Proteins. 2007;69 Suppl 8:68-82
references.pmid: 17894354
references.citation: Nature. 2007 Nov 15;450(7168):383-7
references.pmid: 17952055
references.citation: J Comput Chem. 2007 Apr 30;28(6):1145-52
references.pmid: 17274016
references.citation: Nature. 2008 May 15;453(7193):363-7
references.pmid: 18480818
references.citation: Science. 2000 Aug 4;289(5480):739-45
references.pmid: 10926528
references.citation: Proc Natl Acad Sci U S A. 2008 May 27;105(21):7439-44
references.pmid: 18490656
references.citation: Nat Genet. 2002 Nov;32(3):397-401
references.pmid: 12379855
references.citation: Cell. 2000 Mar 17;100(6):703-11
references.pmid: 10761935
references.citation: Bioinformatics. 2007 Apr 1;23(7):802-8
references.pmid: 17267437
references.citation: BMC Neurosci. 2001;2:6
references.pmid: 11346454
references.citation: Curr Protoc Bioinformatics. 2004 Feb;Chapter 3:Unit3.10
references.pmid: 18428720
references.citation: J Neurosci. 2007 Nov 14;27(46):12630-40
references.pmid: 18003842
references.citation: Science. 2003 Feb 21;299(5610):1221-5
references.pmid: 12595690
references.citation: Nature. 2005 Mar 10;434(7030):225-9
references.pmid: 15759003
references.citation: J Recept Signal Transduct Res. 2006;26(5-6):611-30
references.pmid: 17118801
references.citation: Results Probl Cell Differ. 2009;47:203-20
references.pmid: 19145413
references.citation: Curr Biol. 2005 Jul 26;15(14):1257-65
references.pmid: 16051168
references.citation: Mol Endocrinol. 2007 Feb;21(2):574-80
references.pmid: 17110401
references.citation: Curr Biol. 2005 Feb 22;15(4):322-7
references.pmid: 15723792
references.citation: J Mol Model. 2006 Sep;12(6):931-41
references.pmid: 16607493
references.citation: Curr Protoc Bioinformatics. 2008 Dec;Chapter 8:Unit 8.14
references.pmid: 19085980
references.citation: Nucleic Acids Res. 2006 Jan 1;34(Database issue):D187-91
references.pmid: 16381842
references.citation: Mol Biol Evol. 2006 Feb;23(2):292-300
references.pmid: 16207936
references.citation: Science. 2008 Nov 21;322(5905):1211-7
references.pmid: 18832607
references.citation: Nature. 2006 Nov 16;444(7117):288-94
references.pmid: 17108952
references.citation: PLoS One. 2009 Sep 16;4(9):e7011
references.pmid: 19756152
references.citation: Nature. 2000 Apr 6;404(6778):601-4
references.pmid: 10766242
references.citation: Nature. 2008 Jul 24;454(7203):486-91
references.pmid: 18594507
references.citation: J Comput Aided Mol Des. 1996 Aug;10(4):293-304
references.pmid: 8877701
references.citation: Chem Senses. 2005 Jan;30 Suppl 1:i16
references.pmid: 15738090
references.citation: Cell. 2000 Mar 17;100(6):693-702
references.pmid: 10761934
references.citation: Rev Physiol Biochem Pharmacol. 2005;154:37-72
references.pmid: 16032395
references.citation: Chem Senses. 2004 Sep;29(7):583-93
references.pmid: 15337684
references.citation: J Mol Model. 2007 Mar;13(3):401-9
references.pmid: 17120078
references.citation: Curr Protoc Bioinformatics. 2006 Oct;Chapter 5:Unit-5.6
references.pmid: 18428767
references.citation: Nature. 2008 Sep 25;455(7212):497-502
references.pmid: 18818650
references.citation: J Biol Chem. 2010 Sep 3;285(36):28373-8
references.pmid: 20605788
references.citation: J Med Chem. 2008 May 22;51(10):2907-14
references.pmid: 18442228
references.citation: Proc Natl Acad Sci U S A. 2010 Jun 15;107(24):11110-5
references.pmid: 20534469