Subnanometre-resolution electron cryomicroscopy structure of a heterodimeric ABC exporter.
Subnanometre-resolution electron cryomicroscopy structure of a heterodimeric ABC exporter.
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DOI：
10.1038/nature13872
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发表时间：
2015-01-15
期刊：
影响因子：
64.8
通讯作者：
Cheng, Yifan
中科院分区：
文献类型：
--
作者：
Kim, JungMin;Wu, Shenping;Tomasiak, Thomas M.;Mergel, Claudia;Winter, Michael B.;Stiller, Sebastian B.;Robles-Colmanares, Yaneth;Stroud, Robert M.;Tampe, Robert;Craik, Charles S.;Cheng, Yifan
ATP结合盒（ABC）转运蛋白利用ATP结合和其核苷酸结合域（NBD）水解产生的能量将底物转运穿过细胞膜。ABC输出蛋白存在于原核生物和真核生物中，例如涉及病原体和癌细胞的多药耐药性以及许多人类疾病。TmrAB是来自嗜热革兰氏阴性真细菌嗜热栖热菌的异二聚体ABC输出蛋白，与各种多药物转运蛋白同源，并含有一个在步行者B基序旁边具有非催化残基的简并位点。在这里，我们报告了亚纳米分辨率结构的洗涤剂溶解TmrAB在一个无核苷酸，面向内的构象，通过单粒子电子冷冻显微镜（冷冻EM）。重建清楚地解决了ABC转运蛋白的特征，包括跨膜结构域（TMD）和NBD中的螺旋。TMD中的空腔可从膜的细胞质侧以及从细胞质侧向进入，表明转运蛋白处于面向内的开放构象。两个NBD通过它们的C-末端螺旋保持接触。此外，我们的结构和其他ABC转运蛋白的晶体结构之间的比较表明，可能的轨迹的构象变化，涉及两个NBD之间的滑动和旋转运动的过渡期间，从面向内的面向外的构象。
ATP-binding cassette (ABC) transporters translocate substrates across cell membranes, using energy harnessed from ATP binding and hydrolysis at their nucleotide binding domains (NBDs). ABC exporters are present in both prokaryotes and eukaryotes with examples implicated in multidrug resistance of pathogens and cancer cells, as well as in many human diseases. TmrAB is a heterodimeric ABC exporter from the thermophilic Gram-negative eubacterium Thermus thermophilus homologous to various multidrug transporters and containing one degenerate site with a non-catalytic residue next to the Walker B motif. Here we report a subnanometer resolution structure of detergent-solubilized TmrAB in a nucleotide-free, inward-facing conformation by single particle electron cryomicroscopy (cryo-EM). The reconstructions clearly resolved characteristic features of ABC transporters, including helices in the transmembrane domain (TMD) and NBDs. A cavity in the TMD is accessible laterally from the cytoplasmic side of the membrane as well as from the cytoplasm, indicating that the transporter lies in an inward-facing open conformation. The two NBDs remain in contact via their C-terminal helices. Furthermore, comparison between our structure and the crystal structures of other ABC transporters suggests a possible trajectory of conformational changes that involves a sliding and rotating motion between the two NBDs during the transition from the inward facing to outward facing conformations.
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影响因子：
48
作者：
Kucukelbir, Alp;Sigworth, Fred J.;Tagare, Hemant D.
通讯作者：
Tagare, Hemant D.
电子计数和束诱导运动校正可实现近原子分辨率的单粒子冷冻电镜。
影响因子：
48
作者：
Li, Xueming;Mooney, Paul;Zheng, Shawn;Booth, Christopher R.;Braunfeld, Michael B.;Gubbens, Sander;Agard, David A.;Cheng, Yifan
通讯作者：
Cheng, Yifan
DOI：
10.1126/science.1246489
发表时间：
2014-03-07
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Lee JY;Yang JG;Zhitnitsky D;Lewinson O;Rees DC
通讯作者：
Rees DC
影响因子：
14.9
作者：
Biegert A;Mayer C;Remmert M;Söding J;Lupas AN
通讯作者：
Lupas AN
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