Far-red fluorescent genetically encoded calcium ion indicators [article]

Rochelin Dalangin, Mikhail Drobizhev, Rosana S. Molina, Abhi Aggarwal, Ronak Patel, Ahmed S. Abdelfattah, Yufeng Zhao, Jiahui Wu, Kaspar Podgorski, Eric R. Schreiter, Thomas E. Hughes, Robert E. Campbell (+1 others)
2020 bioRxiv   pre-print
AbstractGenetically encoded calcium ion (Ca2+) indicators (GECIs) are widely-used molecular tools for functional imaging of Ca2+ dynamics and neuronal activities on a single cell level. Here we report the design and development of two new far-red fluorescent GECIs, FR-GECO1a and FR-GECO1c, based on the monomeric far-red fluorescent protein mKelly. We characterized these far-red GECIs as purified proteins and assessed their performance when expressed in cultured neurons. FR-GECOs have excitation
more » ... and emission maxima at ~ 596 nm and ~ 644 nm, respectively, display large responses to Ca2+ (ΔF/F0 = 6 for FR-GECO1a, 18 for FR-GECO1c), and are bright under both one-photon and two-photon illumination. FR-GECOs also have high affinities (apparent Kd = 29 nM for FR-GECO1a, 83 nM for FR-GECO1c) for Ca2+, and they enable sensitive and fast detection of single action potentials in neurons.
doi:10.1101/2020.11.12.380089 fatcat:k7fic3l5t5c7bi3odpfkjamnga