Bioluminescent Indicators for Ca2+ Based on Split Renilla Luciferase Complementation in Living Cells

Department of Bio-Informational Pharmacology, Medical Research Institute, Tokyo Medical and Dental University, Chiyoda, Tokyo 101-0062, Japan.
Analytical Sciences (Impact Factor: 1.39). 02/2008; 24(11):1405-8. DOI: 10.2116/analsci.24.1405
Source: PubMed


Genetically encoded bioluminescent indicators for intracellular Ca2+ are described here with CaM-M13 interaction-induced complementation of split Renilla luciferase. The Ca2+-induced interaction between CaM and M13 leads to complementation of the N- and C-terminal halves of split Renilla luciferase in living cells. This intramolecular interaction results in the spontaneous and simultaneous emission of bioluminescence split Renilla luciferase. This is how intracellular Ca2+ is illuminated with the intramolecular complementation of split Renilla luciferase. The Ca2+-dependent spontaneous and simultaneous emission of bioluminescence promises to reveal Ca2+ dynamics in living cells, and also in vivo using the present indicators.

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    • "To overcome the problem of unintentional activation of cellular processes upon excitation with light in conventional fluorescence imaging, we constructed two bioluminescent indicators modelled after established luciferase-based indicators for Ca2+ 12 and cAMP13141516 (reviewed in [11]; Fig. 2a). These indicators contained a calmodulin-M13 Ca2+ sensor domain (cpGL-CaM) or a mouse protein kinase-A regulatory subunit cAMP-binding domain (cpGL-α-CT) fused to firefly luciferase. "
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