Bright and fast voltage reporters across the visible spectrum via electrochromic FRET (eFRET)

Peng Zou; Yongxin Zhao; Adam D. Douglass; Daniel R. Hochbaum; Daan Brinks; Christopher A. Werley; D. Jed Harrison; Robert E. Campbell; Adam E. Cohen

arXiv · 1403.4636

Bright and fast voltage reporters across the visible spectrum via electrochromic FRET (eFRET)

Peng Zou·Yongxin Zhao·Adam D. Douglass·Daniel R. Hochbaum·Daan Brinks·Christopher A. Werley·D. Jed Harrison·Robert E. Campbell·Adam E. Cohen

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Abstract

We present a palette of brightly fluorescent genetically encoded voltage indicators (GEVIs) with excitation and emission peaks spanning the visible spectrum, sensitivities from 6 - 10% Delta F/F per 100 mV, and half-maximal response times from 1 - 7 ms. A fluorescent protein is fused to an Archaerhodopsin-derived voltage sensor. Voltage-induced shifts in the absorption spectrum of the rhodopsin lead to voltage-dependent nonradiative quenching of the appended fluorescent protein. Through a library screen, we identified linkers and fluorescent protein combinations which reported neuronal action potentials in cultured rat hippocampal neurons with a single-trial signal-to-noise ratio from 6.6 to 11.6 in a 1 kHz imaging bandwidth at modest illumination intensity. The freedom to choose a voltage indicator from an array of colors facilitates multicolor voltage imaging, as well as combination with other optical reporters and optogenetic actuators.

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Peng Zou, Yongxin Zhao, Adam D. Douglass, Daniel R. Hochbaum, Daan Brinks, Christopher A. Werley, D. Jed Harrison, Robert E. Campbell, Adam E. Cohen. 2014-03-18. Bright and fast voltage reporters across the visible spectrum via electrochromic FRET (eFRET). https://arxiv.org/abs/1403.4636

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