Live-cell imaging of single mRNA dynamics using split superfolder green fluorescent proteins with minimal background
- 1Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Korea
- 2Center for RNA Research, Institute for Basic Science, Seoul, 08826, Korea
- 3Institute of Applied Physics, Seoul National University, Seoul, 08826, Korea
- 4Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826, Korea
- Corresponding author: hyeyoon.park{at}snu.ac.kr
Abstract
The MS2 system, with an MS2 binding site (MBS) and an MS2 coat protein fused to a fluorescent protein (MCP–FP), has been widely used to fluorescently label mRNA in live cells. However, one of its limitations is the constant background fluorescence signal generated from free MCP–FPs. To overcome this obstacle, we used a superfolder GFP (sfGFP) split into two or three nonfluorescent fragments that reassemble and emit fluorescence only when bound to the target mRNA. Using the high-affinity interactions of bacteriophage coat proteins with their corresponding RNA binding motifs, we showed that the nonfluorescent sfGFP fragments were successfully brought close to each other to reconstitute a complete sfGFP. Furthermore, real-time mRNA dynamics inside the nucleus as well as the cytoplasm were observed by using the split sfGFPs with the MS2–PP7 hybrid system. Our results demonstrate that the split sfGFP systems are useful tools for background-free imaging of mRNA with high spatiotemporal resolution.
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Footnotes
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Article is online at http://www.rnajournal.org/cgi/doi/10.1261/rna.067835.118.
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Freely available online through the RNA Open Access option.
- Received June 25, 2018.
- Accepted October 20, 2019.
This article, published in RNA, is available under a Creative Commons License (Attribution 4.0 International), as described at http://creativecommons.org/licenses/by/4.0/.
