Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
Center for Integrated Protein Science Munich (CIPSM) at the Lehrstuhl Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany.
J Mol Biol. 2017 Jun 2;429(11):1630-1637. doi: 10.1016/j.jmb.2017.04.003. Epub 2017 Apr 19.
Parallel and antiparallel transmembrane helix-helix interactions support the folding and non-covalent assembly of many integral membrane proteins. While several genetic tools are currently in use to study parallel transmembrane helix-helix interactions, antiparallel associations have been difficult to determine. Here, we present a novel genetic approach, termed BLaTM 2.0, which can be used in combination with the recently presented BLaTM 1.2 to compare the efficiency of antiparallel and parallel transmembrane domain (TMD) interactions in a natural membrane. In a practical application of the BLaTM system, we find that the antiparallel interaction of TMD4, the known dimerization domain of the dual-topology small multidrug transporter EmrE, is sequence-specific and much stronger than the parallel one. This suggests that TMD4 has evolved to favor the formation of dual-topology EmrE dimers over single-topology dimers.
平行和反平行跨膜螺旋-螺旋相互作用支持许多整合膜蛋白的折叠和非共价组装。虽然目前有几种遗传工具可用于研究平行跨膜螺旋-螺旋相互作用，但反平行相互作用一直难以确定。在这里，我们提出了一种新的遗传方法，称为 BLaTM 2.0，它可以与最近提出的 BLaTM 1.2 结合使用，以比较天然膜中反平行和平行跨膜结构域 (TMD) 相互作用的效率。在 BLaTM 系统的实际应用中，我们发现已知双拓扑小分子药物转运蛋白 EmrE 的二聚化结构域 TMD4 的反平行相互作用是序列特异性的，比平行相互作用强得多。这表明 TMD4 已经进化为有利于形成双拓扑 EmrE 二聚体而不是单拓扑二聚体。
