Lee, Sungmoo Song, Yoon-Kyu Baker, Bradley J. 2024-01-19T19:01:51Z 2024-01-19T19:01:51Z 2021-09-05 2019-10-29 1662-5102 https://pubs.kist.re.kr/handle/201004/119426 Genetically-encoded indicators of neuronal activity enable the labeling of a genetically defined population of neurons to optically monitor their activities. However, researchers often find difficulties in identifying relevant signals from excessive background fluorescence. A photoactivatable version of a genetically encoded calcium indicator, sPA-GCaMP6f is a good example of circumventing such an obstacle by limiting the fluorescence to a region of interest defined by the user. Here, we apply this strategy to genetically encoded voltage (GEVI) and pH (GEPI) indicators. Three photoactivatable GEVI candidates were considered. The first one used a circularly-permuted fluorescent protein, the second design involved a Forster resonance energy transfer (FRET) pair, and the third approach employed a pH-sensitive variant of GFP, ecliptic pHluorin. The candidate with a variant of ecliptic pHluorin exhibited photoactivation and a voltage-dependent fluorescence change. This effort also yielded a pH-sensitive photoactivatable GFP that varies its brightness in response to intracellular pH changes. English FRONTIERS MEDIA SA FLUORESCENT-PROTEIN ACTION-POTENTIALS GREEN DYNAMICS SENSORS GFP Engineering Photoactivatability in Genetically Encoded Voltage and pH Indicators Article 10.3389/fncel.2019.00482 1 FRONTIERS IN CELLULAR NEUROSCIENCE, v.13 FRONTIERS IN CELLULAR NEUROSCIENCE 13 scie scopus 000496132200001 2-s2.0-85075250921 Neurosciences Neurosciences & Neurology Article FLUORESCENT-PROTEIN ACTION-POTENTIALS GREEN DYNAMICS SENSORS GFP voltage indicator photoactivatable GEVI pH sensor ecliptic pHluorin PA-GFP PA-Bongwoori-R3 PA-ecliptic pHluorin