Expanded palette of Nano-lanterns for real-time multicolor luminescence imaging

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 112; no. 14; pp. 4352 - 4356
• Main Authors: Takai, Akira, Nakano, Masahiro, Saito, Kenta, Haruno, Remi, Watanabe, Tomonobu M., Ohyanagi, Tatsuya, Jin, Takashi, Okada, Yasushi, Nagai, Takeharu
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 07.04.2015; National Acad Sciences
• Series: From the Cover
• Subjects: Animals; Biological Sciences; Bioluminescence; calcium; Calcium - metabolism; Cell Line; Cellular biology; color; DNA - chemistry; Dogs; Embryonic Stem Cells - cytology; Endosomes - metabolism; Energy transfer; Enzymes; Fluorescence; Fluorescence Resonance Energy Transfer; fluorescent proteins; Focal Adhesions; functional status; Gene Expression Regulation; genes; image analysis; luciferase; Luciferases - chemistry; Luciferases, Renilla - metabolism; Luminescence; Luminescent Proteins - chemistry; Mice; Molecular Sequence Data; monitoring; Oligonucleotides - chemistry; Peroxisomes - metabolism; Photobleaching; Phototoxicity; Promoter Regions, Genetic; Proteins; Recombinant Fusion Proteins - chemistry; Renilla; Vinculin - chemistry; live imaging; luciferase; luminescence imaging; bioluminescence resonance energy transfer; luminescent indicator
• ISSN: 0027-8424; 1091-6490; 1091-6490
• DOI: 10.1073/pnas.1418468112

Fluorescence live imaging has become an essential methodology in modern cell biology. However, fluorescence requires excitation light, which can sometimes cause potential problems, such as autofluorescence, phototoxicity, and photobleaching. Furthermore, combined with recent optogenetic tools, the light illumination can trigger their unintended activation. Because luminescence imaging does not require excitation light, it is a good candidate as an alternative imaging modality to circumvent these problems. The application of luminescence imaging, however, has been limited by the two drawbacks of existing luminescent protein probes, such as luciferases: namely, low brightness and poor color variants. Here, we report the development of bright cyan and orange luminescent proteins by extending our previous development of the bright yellowish-green luminescent protein Nano-lantern. The color change and the enhancement of brightness were both achieved by bioluminescence resonance energy transfer (BRET) from enhancedRenillaluciferase to a fluorescent protein. The brightness of these cyan and orange Nano-lanterns was ∼20 times brighter than wildtypeRenillaluciferase, which allowed us to perform multicolor live imaging of intracellular submicron structures. The rapid dynamics of endosomes and peroxisomes were visualized at around 1-s temporal resolution, and the slow dynamics of focal adhesions were continuously imaged for longer than a few hours without photobleaching or photodamage. In addition, we extended the application of these multicolor Nano-lanterns to simultaneous monitoring of multiple gene expression or Ca²⁺ dynamics in different cellular compartments in a single cell.