Department of Cancer Biology and Pharmacology, University of Illinois College of Medicine, Peoria, IL, United States.
Methods Enzymol. 2021;652:273-291. doi: 10.1016/bs.mie.2021.03.001. Epub 2021 Mar 27.
Incorporation of ion channels in planar lipid bilayers allows detecting and measuring ion channel activity in a well-controlled system. This technique provides critical information about ion channel kinetics, ion selectivity, gating mechanism, open probability, unitary conductance, subconductance states, voltage dependence, and burst opening events, particularly at the single molecule level. Planar lipid bilayers provide a unique controllable environment that enables maintaining specific regulatory components, including lipids, ligands, inhibitors, particular ions, and proteins, as well as the temperature that can modulate activity of many ion channels. Thus, this system provides explicit details about ion channel gating mechanism and enables identifying its particular regulatory molecules or components. This chapter will describe the planar lipid bilayer method using the example of a transient receptor potential (TRP) ion channel family member. The planar lipid bilayer electrophysiological approach has proven to be useful in studying intrinsic properties of TRP channels. This method is particularly valuable for our understanding of intrinsic temperature sensitivity of thermoreceptors such as TRP channels and direct effects of TRP channels agonists, antagonists, co-factors, and other modifiers.
平面脂质双层中离子通道的掺入允许在一个得到良好控制的系统中检测和测量离子通道活性。该技术提供了关于离子通道动力学、离子选择性、门控机制、开放概率、单位电导、亚电导状态、电压依赖性和爆发开放事件的关键信息，特别是在单分子水平上。平面脂质双层提供了一个独特的可控环境，能够维持特定的调节成分，包括脂质、配体、抑制剂、特定离子和蛋白质，以及能够调节许多离子通道活性的温度。因此，该系统提供了关于离子通道门控机制的明确细节，并能够识别其特定的调节分子或成分。本章将以瞬时受体电位 (TRP) 离子通道家族成员为例描述平面脂质双层方法。平面脂质双层电生理学方法已被证明在研究 TRP 通道的固有特性方面非常有用。这种方法对于我们理解热敏受体（如 TRP 通道）的固有温度敏感性以及 TRP 通道激动剂、拮抗剂、辅助因子和其他修饰剂的直接作用特别有价值。
