The full-length mu-opioid receptor:: A conformational study by circular dichroism in trifluoroethanol and membrane-mimetic environments
The full-length mu-opioid receptor:: A conformational study by circular dichroism in trifluoroethanol and membrane-mimetic environments
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DOI：
10.1007/s00232-008-9112-x
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发表时间：
2008-05-01
影响因子：
2.4
通讯作者：
Talmont, Franck
中科院分区：
文献类型：
--
作者：
Muller, Isabelle;Sarramegna, Valerie;Talmont, Franck
通过圆二色性研究了溶解在三氟乙醇 (TFE) 和洗涤剂胶束中的重组人 mu-阿片受体 (HuMOR) 的二级结构含量。在这两种情况下，这种 G 蛋白偶联受体均采用特征性 α 螺旋结构，在圆二色光谱中观察到最小值位于 208 和 222 nm。光谱去卷积后，TFE 和十二烷基硫酸钠（pH 6）中的 α 螺旋含量估计在 50% 范围内。这些值与为 mu-阿片受体确定的预测二级结构含量一致。在去污剂中溶解的受体的二级结构上观察到 pH 依赖性效应，这证明了离子和疏水相互作用对二级结构的重要作用。作为本研究的一部分，还分析了 EGFP-HuMOR（增强型绿色荧光蛋白 (EGFP) 与 mu-阿片受体之间的融合蛋白）和溶解在 TFE 中的 EGFP 的圆二色光谱。
The secondary structure content of the recombinant human mu-opioid receptor (HuMOR) solubilized in trifluoroethanol (TFE) and in detergent micelles was investigated by circular dichroism. In both conditions, this G protein-coupled receptor adopts a characteristic alpha-helical structure, with minima at 208 and 222 nm as observed in the circular dichroism spectra. After deconvolution of spectra, the alpha-helix contents were estimated to be in the range of 50% in TFE and in sodium dodecyl sulfate at pH 6. These values are in accordance with the predicted secondary structure content determined for the mu-opioid receptor. A pH-dependent effect was observed on the secondary structure of the receptor solubilized in detergents, which demonstrates the essential role of ionic and hydrophobic interactions on the secondary structure. Circular dichroism spectra of EGFP-HuMOR, a fusion protein between the enhanced green fluorescent protein (EGFP) and the mu-opioid receptor, and EGFP solubilized in TFE were also analyzed as part of this study.