Refined structures of mouse P-glycoprotein.
Refined structures of mouse P-glycoprotein.
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DOI：
10.1002/pro.2387
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发表时间：
2014-01
期刊：
影响因子：
8
通讯作者：
Aller, Stephen G.
中科院分区：
文献类型：
--
作者：
Li, Jingzhi;Jaimes, Kimberly F.;Aller, Stephen G.
最近确定的C.线虫P-糖蛋白（Pgp）结构与原始小鼠Pgp结构相比显示出显著的偏差，这表明在后一模型中可能存在误解。为了解决这一问题，我们从原始小鼠Pgp数据集的单波长异常色散定相到3.8 μ m分辨率生成了实验电子密度图。与原始MAD图相比，该图显示了更多的细节，并揭示了需要从头构建模型的结构的几个区域。改进的无药物结构被细化到3.8 μ m分辨率，Rwork和Rfree分别降低9.4和8.1%（Rwork = 21.2%，Rfree = 26.6%），蛋白质几何结构得到显著改善。改进的小鼠Pgp模型在有利的Ramachandran区域中含有约95%的残基，而原始模型仅为57%。六个跨膜螺旋的注册表被纠正，揭示了以前未被识别的参与药物结合的氨基酸残基。三个跨膜（TM）4和TM 5的注册表移位（旋转和平移）和添加三个N-末端残基是必要的，并与新的汞标记和异常傅立叶密度进行了验证。TM 4的校正位置（其形成用于药物进入的门户的框架）使主链原子从其原始位置移位>6 π。小鼠Pgp的药物转运途径与人Pgp有96%的相同性，并且富含芳香族残基，这些残基可能在允许高度多特异性底物识别方面发挥集体作用。
The recently determined C. elegans P-glycoprotein (Pgp) structure revealed significant deviations compared to the original mouse Pgp structure, which suggested possible misinterpretations in the latter model. To address this concern, we generated an experimental electron density map from single-wavelength anomalous dispersion phasing of an original mouse Pgp dataset to 3.8 Å resolution. The map exhibited significantly more detail compared to the original MAD map and revealed several regions of the structure that required de novo model building. The improved drug-free structure was refined to 3.8 Å resolution with a 9.4 and 8.1% decrease in Rwork and Rfree, respectively, (Rwork = 21.2%, Rfree = 26.6%) and a significant improvement in protein geometry. The improved mouse Pgp model contains ∼95% of residues in the favorable Ramachandran region compared to only 57% for the original model. The registry of six transmembrane helices was corrected, revealing amino acid residues involved in drug binding that were previously unrecognized. Registry shifts (rotations and translations) for three transmembrane (TM)4 and TM5 and the addition of three N-terminal residues were necessary, and were validated with new mercury labeling and anomalous Fourier density. The corrected position of TM4, which forms the frame of a portal for drug entry, had backbone atoms shifted >6 Å from their original positions. The drug translocation pathway of mouse Pgp is 96% identical to human Pgp and is enriched in aromatic residues that likely play a collective role in allowing a high degree of polyspecific substrate recognition.
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影响因子：
2.9
作者：
Loo, Tip W.;Clarke, David M.
通讯作者：
Clarke, David M.
DOI：
10.1107/s090744490200118x
发表时间：
2002-03-01
期刊：
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY
影响因子：
--
作者：
Dauter, Z;Dauter, M;Dodson, E
通讯作者：
Dodson, E
DOI：
10.1107/s0907444904019158
发表时间：
2004-12-01
影响因子：
2.2
作者：
Emsley, P;Cowtan, K
通讯作者：
Cowtan, K
DOI：
10.1073/pnas.94.23.12291
发表时间：
1997-11-11
影响因子：
11.1
作者：
Borhani, DW;Rogers, DP;Brouillette, CG
通讯作者：
Brouillette, CG
DOI：
10.1126/science.1168750
发表时间：
2009-03-27
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Aller SG;Yu J;Ward A;Weng Y;Chittaboina S;Zhuo R;Harrell PM;Trinh YT;Zhang Q;Urbatsch IL;Chang G
通讯作者：
Chang G