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bioRxiv · 10.1101/2022.12.27.522013

Improved genetically encoded fluorescent biosensors for monitoring of intra- and extracellular L-lactate

Nasu, Y.·Aggarwal, A.·Le, G. N. T.·Kamijo, Y.·Boisvert, M.·Paquet, M.-E.·Drobizhev, M.·Podgorski, K.·Campbell, R. E.
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Abstract

O_SCPLOWLC_SCPLOW-Lactate is increasingly appreciated as a key metabolite and signaling molecule in mammals. To enable investigations of both the inter- and intra-cellular dynamics of O_SCPLOWLC_SCPLOW-Lactate, we develop a second-generation green fluorescent extracellular O_SCPLOWLC_SCPLOW-Lactate biosensor, designated eLACCO2.1, and a red fluorescent intracellular O_SCPLOWLC_SCPLOW-Lactate biosensor, designated R-iLACCO1. Compared to the first-generation eLACCO1.1 ({Delta}F/F = 1.5 in cultured neurons), eLACCO2.1 exhibits better membrane localization and fluorescence response ({Delta}F/F = 8.1 in cultured neurons) with faster response kinetics to extracellular O_SCPLOWLC_SCPLOW-Lactate on the surface of live mammalian cells. R-iLACCO1 and its affinity variants exhibit large fluorescence responses to changes in O_SCPLOWLC_SCPLOW-Lactate concentration in vitro ({Delta}F/F = 15 to 22) and in live mammalian cells ({Delta}F/F = 5.5 to 11). We demonstrate that these biosensors enable cellular-resolution imaging of extracellular and intracellular O_SCPLOWLC_SCPLOW-Lactate in cultured mammalian cells.

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Nasu, Y., Aggarwal, A., Le, G. N. T., Kamijo, Y., Boisvert, M., Paquet, M.-E., Drobizhev, M., Podgorski, K., Campbell, R. E.. 2022-12-27. Improved genetically encoded fluorescent biosensors for monitoring of intra- and extracellular L-lactate. https://doi.org/10.1101/2022.12.27.522013

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