Fluorescence Imaging of Cellular Metabolites with RNA

Department of Pharmacology, Weill Medical College, Cornell University, New York, NY 10065, USA.
Science (Impact Factor: 33.61). 03/2012; 335(6073):1194. DOI: 10.1126/science.1218298
Source: PubMed


Genetically encoded sensors are powerful tools for imaging intracellular metabolites and signaling molecules. However, developing sensors is challenging because they require proteins that undergo conformational changes upon binding the desired target molecule. We describe an approach for generating fluorescent sensors based on Spinach, an RNA sequence that binds and activates the fluorescence of a small-molecule fluorophore. We show that these sensors can detect a variety of different small molecules in vitro and in living cells. These RNAs constitute a versatile approach for fluorescence imaging of small molecules and have the potential to detect essentially any cellular biomolecule.

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Available from: Wenjiao Song,
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    • "Spinach resembles enhanced GFP emitting a green fluorescence that is remarkably resistant to photobleaching (51). Trafficking of Spinach-fused RNAs was successfully imaged in live cells without nonspecific fluorescence or cytotoxicity in cells (51,52). "
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    • "Several alternative approaches to intracellular pH measurement have been proposed including surface enhanced Raman scattering (SERS) based sensors (Kneipp et al., 2010), green florescent protein (GFP) based sensors (Kneen et al., 1998), and RNA based sensors (Paige et al., 2012). However, the most widely implemented approach utilizes pH-sensitive fluorophores. "
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