Making structural sense of dimerization interfaces of delta opioid receptor homodimers.
Making structural sense of dimerization interfaces of delta opioid receptor homodimers.
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DOI：
10.1021/bi101474v
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发表时间：
2011-03-15
期刊：
影响因子：
2.9
通讯作者：
Filizola, Marta
中科院分区：
文献类型：
--
作者：
Johnston, Jennifer M.;Aburi, Mahalaxmi;Provasi, Davide;Bortolato, Andrea;Urizar, Eneko;Lambert, Nevin A.;Javitch, Jonathan A.;Filizola, Marta
与G蛋白偶联受体（GPCR）家族的其他成员一样，阿片受体已被证明在质膜上形成二聚体和/或低聚体。这种联系是稳定的还是短暂的尚不清楚。最近令人信服的证据表明，至少有一些gpcr能迅速结合和分离。我们最近从自由能估计中计算了结合亲和力，以预测涉及第四跨膜（TM4）螺旋（此处称为“4”二聚体）的对称界面上小鼠δ阿片受体（DOR）原聚物之间的瞬时关联。在这里，我们提出了在TM4或TM5的细胞外末端取代半胱氨酸的DOR构建物的二硫交联实验，证实了涉及这些螺旋的DOR复合物的形成。我们的结果与TM4和/或TM5参与DOR同型二聚体界面一致，但可能具有不同的关联倾向。在明确的脂质-水环境中，对涉及TM4单独或与TM5（这里称为“4/5”二聚体）的两种不同的DOR二聚体排列进行了粗粒度（CG）调质元动力学模拟，证实了4二聚体的两种结构和能量相似的构型的存在，正如之前通过伞式抽样计算评估的那样，并揭示了4/5二聚体的单个能量最小值。另外对4/5二聚体的CG伞采样模拟表明，DOR原聚体之间的结合强度取决于界面上的蛋白质区域，4二聚体比4/5二聚体更稳定。
Opioid receptors, like other members of the G protein-coupled receptor (GPCR) family, have been shown to associate to form dimers and/or oligomers at the plasma membrane. Whether this association is stable or transient is not known. Recent compelling evidence suggests that at least some GPCRs rapidly associate and dissociate. We have recently calculated binding affinities from free energy estimates to predict transient association between mouse delta opioid receptor (DOR) protomers at a symmetric interface involving the fourth transmembrane (TM4) helix (herein termed “4” dimer). Here we present disulfide cross-linking experiments with DOR constructs with cysteines substituted at the extracellular ends of TM4 or TM5 that confirm the formation of DOR complexes involving these helices. Our results are consistent with the involvement of TM4 and/or TM5 at the DOR homodimer interface, but possibly with differing association propensities. Coarse-grained (CG) well-tempered metadynamics simulations of two different dimeric arrangements of DOR involving TM4 alone or with TM5 (herein termed “4/5” dimer) in an explicit lipid−water environment confirmed the presence of two structurally and energetically similar configurations of the 4 dimer, as previously assessed by umbrella sampling calculations, and revealed a single energetic minimum of the 4/5 dimer. Additional CG umbrella sampling simulations of the 4/5 dimer indicated that the strength of association between DOR protomers varies depending on the protein region at the interface, with the 4 dimer being more stable than the 4/5 dimer.
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影响因子：
5.5
作者：
Hess, Berk;Kutzner, Carsten;Lindahl, Erik
通讯作者：
Lindahl, Erik
影响因子：
4.4
作者：
Bussi, Giovanni;Zykova-Timan, Tatyana;Parrinello, Michele
通讯作者：
Parrinello, Michele
影响因子：
4.8
作者：
Hastrup, H;Sen, N;Javitch, JA
通讯作者：
Javitch, JA
影响因子：
4.8
作者：
Hollins B;Kuravi S;Digby GJ;Lambert NA
通讯作者：
Lambert NA
DOI：
10.1073/pnas.0907915107
发表时间：
2010-02-09
影响因子：
11.1
作者：
Hern, Jonathan A.;Baig, Asma H.;Birdsall, Nigel J. M.
通讯作者：
Birdsall, Nigel J. M.