小柯机器人

美国波士顿大学Jerry L. Chen等研究人员合作实现大型神经元群体的高速弱光在体双光子电压成像。该项研究成果于2023年3月27日在线发表在《自然—方法学》杂志上。

研究人员开发了一种针对低双光子通量的替代方法，即低于射出噪声极限的电压成像。这个框架包括开发具有改进的脉冲检测功能的正向电压指示器（SpikeyGi和SpikeyGi2）；用于在0.4毫米×0.4毫米视场内进行千赫兹帧率成像的双光子显微镜（'SMURF'）；以及用于从拍摄噪声限制信号中推断荧光的自监督去噪算法（DeepVID）。通过这些综合进展，研究人员在清醒的行为小鼠身上实现了1小时内对100多个密集标记的神经元同时进行高速深部组织成像。这证明了在不断增加的神经元群体中进行电压成像的可扩展方法。

据了解，在行为相关的时间尺度上监测大型神经元群体的脉冲活动对于理解神经回路功能至关重要。与钙成像不同，电压成像需要千赫兹的采样率，从而使荧光检测降低到接近射出噪声水平。高光子通量激发可以克服光子有限的发射噪声，但光漂白和光损伤限制了同时成像的神经元的数量和时间。

附：英文全文

Title: High-speed low-light in vivo two-photon voltage imaging of large neuronal populations

Author: Platisa, Jelena, Ye, Xin, Ahrens, Allison M., Liu, Chang, Chen, Ichun Anderson, Davison, Ian G., Tian, Lei, Pieribone, Vincent A., Chen, Jerry L.

Issue&Volume: 2023-03-27

Abstract: Monitoring spiking activity across large neuronal populations at behaviorally relevant timescales is critical for understanding neural circuit function. Unlike calcium imaging, voltage imaging requires kilohertz sampling rates that reduce fluorescence detection to near shot-noise levels. High-photon flux excitation can overcome photon-limited shot noise, but photobleaching and photodamage restrict the number and duration of simultaneously imaged neurons. We investigated an alternative approach aimed at low two-photon flux, which is voltage imaging below the shot-noise limit. This framework involved developing positive-going voltage indicators with improved spike detection (SpikeyGi and SpikeyGi2); a two-photon microscope (‘SMURF’) for kilohertz frame rate imaging across a 0.4mm×0.4mm field of view; and a self-supervised denoising algorithm (DeepVID) for inferring fluorescence from shot-noise-limited signals. Through these combined advances, we achieved simultaneous high-speed deep-tissue imaging of more than 100 densely labeled neurons over 1 hour in awake behaving mice. This demonstrates a scalable approach for voltage imaging across increasing neuronal populations.

DOI: 10.1038/s41592-023-01820-3

Source: https://www.nature.com/articles/s41592-023-01820-3

Nature Methods：《自然—方法学》，创刊于2004年。隶属于施普林格·自然出版集团，最新IF：47.99
官方网址：https://www.nature.com/nmeth/
投稿链接：https://mts-nmeth.nature.com/cgi-bin/main.plex