Autonomous molecular bioluminescent reporter (AMBER) for voltage imaging in freely moving animals

TitleAutonomous molecular bioluminescent reporter (AMBER) for voltage imaging in freely moving animals
Publication TypeJournal Article
Year of Publication2021
AuthorsSrinivasan P, Griffin NM, Thakur DP, Joshi PM, Nguyen-Le A, McCotter S, Jain A, Saeidi M, Kulkarni P, Eisdorfer JT, Rothman JH, Montell C, Theogarajan L
JournalAdv Biol (Weinh)
Volume5
Issue12
Paginatione2100842
Date Published2021 12
ISSN2701-0198
KeywordsAnimals, Caenorhabditis elegans, Diagnostic Imaging, Luciferins, Luminescent Measurements, Neurons
Abstract

Genetically encoded reporters have greatly increased our understanding of biology. While fluorescent reporters have been widely used, photostability and phototoxicity have hindered their use in long-term experiments. Bioluminescence overcomes some of these challenges but requires the addition of an exogenous luciferin limiting its use. Using a modular approach, Autonomous Molecular BioluminEscent Reporter (AMBER), an indicator of membrane potential is engineered. Unlike other bioluminescent systems, AMBER is a voltage-gated luciferase coupling the functionalities of the Ciona voltage-sensing domain (VSD) and bacterial luciferase, luxAB. When co-expressed with the luciferin-producing genes, AMBER reversibly switches the bioluminescent intensity as a function of membrane potential. Using biophysical and biochemical methods, it is shown that AMBER switches its enzymatic activity from an OFF to an ON state as a function of the membrane potential. Upon depolarization, AMBER switches from a low to a high enzymatic activity state, showing a several-fold increase in the bioluminescence output (ΔL/L). AMBER in the pharyngeal muscles and mechanosensory touch neurons of Caenorhabditis elegans is expressed. Using the compressed sensing approach, the electropharingeogram of the C. elegans pharynx is reconstructed, validating the sensor in vivo. Thus, AMBER represents the first fully genetically encoded bioluminescent reporter without requiring exogenous luciferin addition.

DOI10.1002/adbi.202100842
Alternate JournalAdv Biol (Weinh)
PubMed ID34761564
PubMed Central IDPMC8858017
Grant ListR01 HD081266 / HD / NICHD NIH HHS / United States
EY010852 / NH / NIH HHS / United States
1R01HD082347 / NH / NIH HHS / United States
R01 AI169386 / AI / NIAID NIH HHS / United States
R01 EY008117 / EY / NEI NIH HHS / United States
EY008117 / NH / NIH HHS / United States
1R01HD081266 / NH / NIH HHS / United States
R01 HD082347 / HD / NICHD NIH HHS / United States
R01 EY010852 / EY / NEI NIH HHS / United States