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Title: Improved genetically encoded near-infrared fluorescent calcium ion indicators for in vivo imaging
Near-infrared (NIR) genetically encoded calcium ion (Ca 2+ ) indicators (GECIs) can provide advantages over visible wavelength fluorescent GECIs in terms of reduced phototoxicity, minimal spectral cross talk with visible light excitable optogenetic tools and fluorescent probes, and decreased scattering and absorption in mammalian tissues. Our previously reported NIR GECI, NIR-GECO1, has these advantages but also has several disadvantages including lower brightness and limited fluorescence response compared to state-of-the-art visible wavelength GECIs, when used for imaging of neuronal activity. Here, we report 2 improved NIR GECI variants, designated NIR-GECO2 and NIR-GECO2G, derived from NIR-GECO1. We characterized the performance of the new NIR GECIs in cultured cells, acute mouse brain slices, and Caenorhabditis elegans and Xenopus laevis in vivo. Our results demonstrate that NIR-GECO2 and NIR-GECO2G provide substantial improvements over NIR-GECO1 for imaging of neuronal Ca 2+ dynamics.  more » « less
Award ID(s):
1848029
PAR ID:
10294007
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Editor(s):
Lishko, Polina V.
Date Published:
Journal Name:
PLOS Biology
Volume:
18
Issue:
11
ISSN:
1545-7885
Page Range / eLocation ID:
e3000965
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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