Membrane voltage (V m) is a fundamental biological parameter that is essential for neuronal communication, cardiac activity, transmembrane transport, regulation of signaling, and bacterial motility. Optical measurements of V m promise new insights into how voltage propagates within and between cells, but effective optical contrast agents have been lacking. Microbial rhodopsin-based fluorescent voltage indicators are exquisitely sensitive and fast, but very dim, necessitating careful attention to experimental procedures. This chapter describes how to make optical voltage measurements with microbial rhodopsins. © 2014 Springer Science+Business Media, LLC.
Cohen, A. E., & Hochbaum, D. R. (2014). Measuring membrane voltage with microbial rhodopsins. Methods in Molecular Biology, 1071, 97–108. https://doi.org/10.1007/978-1-62703-622-1_8