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: 1.57). 02/2008; 24(11):1405-8. DOI: 10.2116/analsci.24.1405
Source: PubMed

ABSTRACT 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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