Simultaneous dual-color calcium imaging in freely-behaving mice

Dong, Z.; Feng, Y.; Diego, K.; Baggetta, A. M.; Sweis, B. M.; Pennington, Z. T.; Lamsifer, S. I.; Zaki, Y.; Sangiuliano, F.; Philipsberg, P. A.; Morales-Rodriguez, D.; Kircher, D. M.; Slesinger, P.; Shuman, T.; Aharoni, D.; Cai, D. J.

doi:10.1101/2024.07.03.601770

bioRxiv · 10.1101/2024.07.03.601770

Simultaneous dual-color calcium imaging in freely-behaving mice

Dong, Z.·Feng, Y.·Diego, K.·Baggetta, A. M.·Sweis, B. M.·Pennington, Z. T.·Lamsifer, S. I.·Zaki, Y.·Sangiuliano, F.·Philipsberg, P. A.·Morales-Rodriguez, D.·Kircher, D. M.·Slesinger, P.·Shuman, T.·Aharoni, D.·Cai, D. J.

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Abstract

Miniaturized fluorescence microscopes (miniscopes) enable imaging of calcium events from a large population of neurons in freely behaving animals. Traditionally, miniscopes have only been able to record from a single fluorescence wavelength. Here, we present a new open-source dual-channel Miniscope that simultaneously records two wavelengths in freely behaving animals. To enable simultaneous acquisition of two fluorescent wavelengths, we incorporated two CMOS sensors into a single Miniscope. To validate our dual-channel Miniscope, we imaged hippocampal CA1 region that co-expressed a dynamic calcium indicator (GCaMP) and a static nuclear signal (tdTomato) while mice ran on a linear track. Our results suggest that, even when neurons were registered across days using tdTomato signals, hippocampal spatial coding changes over time. In conclusion, our novel dual-channel Miniscope enables imaging of two fluorescence wavelengths with minimal crosstalk between the two channels, opening the doors to a multitude of new experimental possibilities. TeaserNovel open-source dual-channel Miniscope that simultaneously records two wavelengths with minimal crosstalk in freely behaving animals.

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Dong, Z., Feng, Y., Diego, K., Baggetta, A. M., Sweis, B. M., Pennington, Z. T., Lamsifer, S. I., Zaki, Y., Sangiuliano, F., Philipsberg, P. A., Morales-Rodriguez, D., Kircher, D. M., Slesinger, P., Shuman, T., Aharoni, D., Cai, D. J.. 2024-07-05. Simultaneous dual-color calcium imaging in freely-behaving mice. https://doi.org/10.1101/2024.07.03.601770

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