南京大学Xu, Jing-Juan团队近日研究了在活细胞中成像离子通道活性的电化学调制干涉散射显微镜。2025年6月5日出版的《自然—光子学》杂志发表了该成果。
研究细胞内的离子通道活性和信号相互作用是神经科学的关键任务。电生理活动通常用膜片钳或电压敏感成像来测量。不幸的是，这些技术在单通道灵敏度和高通量检测之间存在权衡。
研究组介绍了一种无标记电化学调制干涉散射显微镜（EM iSCAT），用于在全细胞和单通道水平上测量活细胞上的离子通道活性。他们可视化细胞对渗透刺激的反应动力学，并以1.5的帧速率记录单受体通道的开闭轨迹 kHz。研究组还定位和区分细胞膜上不同类型的离子通道，包括Na+、K+和Ca2+，并监测网络中不同细胞之间的时空异质性反应。
EM iSCAT显微镜的高通量和单通道灵敏度能够同时监测单个通道的活性、它们在细胞群落中的定位和聚集。EM iSCAT有可能研究任何类型的离子通道，更广泛地说，是离子通道介导的细胞通讯途径。
附：英文原文
Title: Electrochemically modulated interferometric scattering microscopy for imaging ion channel activity in live cells
Author: Li, Qing-Yue, Lyu, Pin-Tian, Kang, Bin, Chen, Hong-Yuan, Xu, Jing-Juan
Issue&Volume: 2025-06-05
Abstract: Studying ion channel activity and signalling interactions within cells are key tasks in neuroscience. Electrophysiological activities are typically measured with patch-clamp or voltage-sensitive imaging. Unfortunately, these techniques suffer from a trade-off between single-channel sensitivity and high-throughput detection. Here we introduce a label-free electrochemically modulated interferometric scattering microscope (EM-iSCAT) to measure ion channel activity on live cells at both the whole-cell and single-channel levels. We visualize the cellular responses dynamics to osmotic stimulation and record open–close trajectories of single receptor channels with a frame rate of 1.5kHz. We also localize and distinguish different types of ion channels, including Na+, K+ and Ca2+, on the cell membrane and monitor spatio-temporal heterogeneous responses between different cells in a network. The high-throughput and single-channel sensitivity of EM-iSCAT microscopy enables the simultaneous monitoring of the activity of individual channels, their localization and clustering in the cellular community. EM-iSCAT has the potential to enable the study of any type of ion channel and, more broadly, cell communication pathways mediated by ion channels.
DOI: 10.1038/s41566-025-01696-z
Source: https://www.nature.com/articles/s41566-025-01696-z