Ligand-dependent conformations and dynamics of the serotonin 5-HT(2A) receptor determine its activation and membrane-driven oligomerization properties.
Ligand-dependent conformations and dynamics of the serotonin 5-HT(2A) receptor determine its activation and membrane-driven oligomerization properties.
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DOI：
10.1371/journal.pcbi.1002473
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发表时间：
2012
影响因子：
4.3
通讯作者：
Weinstein H
中科院分区：
文献类型：
--
作者：
Shan J;Khelashvili G;Mondal S;Mehler EL;Weinstein H
From computational simulations of a serotonin 2A receptor (5-HT2AR) model complexed with pharmacologically and structurally diverse ligands we identify different conformational states and dynamics adopted by the receptor bound to the full agonist 5-HT, the partial agonist LSD, and the inverse agonist Ketanserin. The results from the unbiased all-atom molecular dynamics (MD) simulations show that the three ligands affect differently the known GPCR activation elements including the toggle switch at W6.48, the changes in the ionic lock between E6.30 and R3.50 of the DRY motif in TM3, and the dynamics of the NPxxY motif in TM7. The computational results uncover a sequence of steps connecting these experimentally-identified elements of GPCR activation. The differences among the properties of the receptor molecule interacting with the ligands correlate with their distinct pharmacological properties. Combining these results with quantitative analysis of membrane deformation obtained with our new method (Mondal et al, Biophysical Journal 2011), we show that distinct conformational rearrangements produced by the three ligands also elicit different responses in the surrounding membrane. The differential reorganization of the receptor environment is reflected in (i)-the involvement of cholesterol in the activation of the 5-HT2AR, and (ii)-different extents and patterns of membrane deformations. These findings are discussed in the context of their likely functional consequences and a predicted mechanism of ligand-specific GPCR oligomerization. The 5-HT2A receptor for the neurotransmitter serotonin (5-HT) belongs to family A (rhodopsin-like) G-protein coupled receptors (GPCRs), one of the most important classes of membrane proteins that are targeted by an extensive and diverse collection of external stimuli. Recently we learned that different ligands targeting the same GPCR can elicit different biological responses, but the mechanisms remain unknown. We address this fundamental question for the serotonin 5-HT2A receptor, because it is known to respond to the binding of structurally diverse ligands by producing similar stimuli in the cell, and to the binding of quite similar ligands with dramatically different responses. Molecular dynamics simulations of molecular models of the serotonin 5-HT2A receptor in complex with pharmacologically distinct ligands show the dynamic rearrangements of the receptor molecule to be different for these ligands, and the nature and extents of the rearrangements reflect the known pharmacological properties of the ligands as full, partial or inverse activators of the receptor. The different rearrangements of the receptor molecule are shown to produce different rearrangements of the surrounding membrane, a remodeling of the environment that can have differential ligand-determined effects on receptor function and association in the cell's membrane.
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DOI：
10.1073/pnas.0811065106
发表时间：
2009-03-24
影响因子：
11.1
作者：
Dror, Ron O.;Arlow, Daniel H.;Shaw, David E.
通讯作者：
Shaw, David E.
影响因子：
4.4
作者：
ESSMANN, U;PERERA, L;PEDERSEN, LG
通讯作者：
PEDERSEN, LG
影响因子：
5.8
作者：
Bosier, Barbara;Muccioli, Giulio G.;Lambert, Didier M.
通讯作者：
Lambert, Didier M.
影响因子：
3.5
作者：
Filizola, Marta;Wang, Simon X.;Weinstein, Harel
通讯作者：
Weinstein, Harel
影响因子：
3.4
作者：
Bennett, Michael P.;Mitchell, Drake C.
通讯作者：
Mitchell, Drake C.