Empson Ruth M, Goulton Chelsea, Scholtz David, Gallero-Salas Yasir, Zeng Hongkui, Knöpfel Thomas
Department of Physiology, Brain Health Research Centre, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
Department of Physiology, Brain Health Research Centre, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.
Physiol Rep. 2015 Jul 29;3(7). doi: 10.14814/phy2.12468.
Understanding how behavior emerges from brain electrical activity is one of the ultimate goals of neuroscience. To achieve this goal we require methods for large-scale recording of the electrical activity of specific neuronal circuits. A very promising approach is to use optical reporting of membrane voltage transients, particularly if the voltage reporter is genetically targeted to specific neuronal populations. Targeting in this way allows population signals to be recorded and interpreted without blindness to neuronal diversity. Here, we evaluated the voltage-sensitive fluorescent protein, VSFP Butterfly 2.1, a genetically encoded voltage indicator (GEVI), for monitoring electrical activity of layer 2/3 cortical pyramidal neurons in mouse brain slices. Standard widefield fluorescence and two-photon imaging revealed robust, high signal-to-noise ratio read-outs of membrane voltage transients that are predominantly synaptic in nature and can be resolved as discrete areas of synaptically connected layer 2/3 neurons. We find that targeted expression of this GEVI in the cortex provides a flexible and promising tool for the analysis of L2/3 cortical network function.
理解行为如何从脑电活动中产生是神经科学的最终目标之一。为实现这一目标，我们需要能够大规模记录特定神经元回路电活动的方法。一种非常有前景的方法是利用膜电压瞬变的光学报告，特别是当电压报告分子通过基因靶向特定神经元群体时。以这种方式进行靶向能够记录和解读群体信号，而不会忽视神经元的多样性。在这里，我们评估了电压敏感荧光蛋白VSFP Butterfly 2.1（一种基因编码电压指示剂，GEVI），用于监测小鼠脑片中层2/3皮质锥体神经元的电活动。标准的宽场荧光成像和双光子成像揭示了膜电压瞬变的强大、高信噪比读出信号，这些信号主要是突触性质的，并且可以解析为层2/3突触连接神经元的离散区域。我们发现，这种GEVI在皮质中的靶向表达为分析L2/3皮质网络功能提供了一种灵活且有前景的工具。
