Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT.
J Gen Physiol. 2020 Mar 2;152(3). doi: 10.1085/jgp.201811998.
Transient receptor potential (TRP) ion channels are evolutionarily ancient sensory proteins that detect and integrate a wide range of physical and chemical stimuli. TRP channels are fundamental for numerous biological processes and are therefore associated with a multitude of inherited and acquired human disorders. In contrast to many other major ion channel families, high-resolution structures of TRP channels were not available before 2013. Remarkably, however, the subsequent "resolution revolution" in cryo-EM has led to an explosion of TRP structures in the last few years. These structures have confirmed that TRP channels assemble as tetramers and resemble voltage-gated ion channels in their overall architecture. But beyond the relatively conserved transmembrane core embedded within the lipid bilayer, each TRP subtype appears to be endowed with a unique set of soluble domains that may confer diverse regulatory mechanisms. Importantly, TRP channel TR structures have revealed sites and mechanisms of action of numerous synthetic and natural compounds, as well as those for endogenous ligands such as lipids, Ca2+, and calmodulin. Here, I discuss these recent findings with a particular focus on the conserved transmembrane region and how these structures may help to rationally target this important class of ion channels for the treatment of numerous human conditions.
瞬时受体电位 (TRP) 离子通道是进化上古老的感觉蛋白,可检测和整合广泛的物理和化学刺激。TRP 通道对许多生物过程至关重要,因此与多种遗传性和获得性人类疾病有关。与许多其他主要离子通道家族不同,2013 年之前没有 TRP 通道的高分辨率结构。然而,令人惊讶的是,随后冷冻电镜中的“分辨率革命”导致 TRP 结构在过去几年中爆发式增长。这些结构证实,TRP 通道作为四聚体组装,其整体结构类似于电压门控离子通道。但除了嵌入脂质双层中的相对保守的跨膜核心之外,每个 TRP 亚型似乎都具有独特的一组可溶性结构域,这些结构域可能赋予不同的调节机制。重要的是,TRP 通道 TR 结构揭示了许多合成和天然化合物以及内源性配体(如脂质、Ca2+和钙调蛋白)的作用部位和机制。在这里,我特别关注保守的跨膜区域,并讨论这些最新发现,以及这些结构如何帮助合理靶向这一重要的离子通道类,以治疗许多人类疾病。