Two-photon excitation of channelrhodopsin-2 at saturation

被引：208

作者：

Rickgauer, John Peter ^{[1
,2
,3
]}

Tank, David W. ^{[1
,2
,3
,4
]}

机构：

[1] Princeton Univ, Dept Mol Biol, Princeton, NJ 08544 USA

[2] Princeton Univ, Lewis Sigler Inst Integrat Genom, Princeton, NJ 08544 USA

[3] Princeton Univ, Princeton Neurosci Inst, Carl Icahn Lab, Princeton, NJ 08544 USA

[4] Princeton Univ, Dept Phys, Princeton, NJ 08544 USA

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 2009年 / 106卷 / 35期

基金：

美国国家卫生研究院; 美国国家科学基金会;

关键词：

optogenetics; photostimulation; laser-scanning microscopy; PHOTOACTIVATION; ILLUMINATION; CORTEX;

D O I：

10.1073/pnas.0907084106

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

We demonstrate that channelrhodopsin-2 (CR), a light-gated ion channel that is conventionally activated by using visible-light excitation, can also be activated by using IR two-photon excitation (TPE). An empirical estimate of CR's two-photon absorption cross-section at lambda = 920 nm is presented, with a value (260 +/- 20 GM) indicating that TPE stimulation of CR photocurrents is not typically limited by intrinsic molecular excitability [1 GM = 10(-50)(cm(4) s)/photon]. By using direct physiological measurements of CR photocurrents and a model of ground-state depletion, we evaluate how saturation of CR's current-conducting state influences the spatial resolution of focused TPE photostimulation, and how photocurrents stimulated by using low-power scanning TPE temporally summate. We show that TPE, like visible-light excitation, can be used to stimulate action potentials in cultured CR-expressing neurons.

引用

页码：15025 / 15030

页数：6

共 24 条

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