Berndt André, Yizhar Ofer, Gunaydin Lisa A, Hegemann Peter, Deisseroth Karl
Institute of Biology, Experimental Biophysics, Humboldt-University, Invalidenstrasse 42, D-10115 Berlin, Germany.
Nat Neurosci. 2009 Feb;12(2):229-34. doi: 10.1038/nn.2247. Epub 2008 Dec 8.
Here we describe bi-stable channelrhodopsins that convert a brief pulse of light into a stable step in membrane potential. These molecularly engineered probes nevertheless retain millisecond-scale temporal precision. Photocurrents can be precisely initiated and terminated with different colors of light, but operate at vastly longer time scales than conventional channelrhodopsins as a result of modification at the C128 position that extends the lifetime of the open state. Because of their enhanced kinetic stability, these step-function tools are also effectively responsive to light at orders of magnitude lower intensity than wild-type channelrhodopsins. These molecules therefore offer important new capabilities for a broad range of in vivo applications.
在此，我们描述了一种双稳态通道视紫红质，它能将短暂的光脉冲转化为膜电位的稳定阶跃。然而，这些经过分子工程改造的探针仍保持毫秒级的时间精度。光电流可以用不同颜色的光精确启动和终止，但由于在C128位置的修饰延长了开放状态的寿命，其作用时间尺度比传统通道视紫红质长得多。由于其增强的动力学稳定性，这些阶跃函数工具对光的响应强度也比野生型通道视紫红质低几个数量级。因此，这些分子为广泛的体内应用提供了重要的新功能。
