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bioRxiv · 10.1101/2021.05.14.443815

An updated suite of viral vectors for in vivo calcium imaging using local and retro-orbital injections

Grodem, S.·Nymoen, I.·Vatne, G. H.·Bjornsdottir, V.·Lensjo, K. K.·Fyhn, M.
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Abstract

Calcium imaging using genetically encoded Ca2+ indicators (GECIs) is a widely adopted method to measure neural activity in modern neuroscience. Here, we explore the use of systemically administered viral vectors for brain-wide expression of GECIs, and adapt novel GECIs to optimize signal-to-noise. We show that systemic injections of PHP.eB AAVs to express GECIs is a highly promising technique for imaging neural activity and circumvent the need for transgenic GECI expressing mouse lines. We also establish the use of soma-targeted GECIs that outperform current Ca2+ indicators using both systemic and local virus injections.

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Grodem, S., Nymoen, I., Vatne, G. H., Bjornsdottir, V., Lensjo, K. K., Fyhn, M.. 2021-05-16. An updated suite of viral vectors for in vivo calcium imaging using local and retro-orbital injections. https://doi.org/10.1101/2021.05.14.443815

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