The central dogma of molecular biology — DNA makes RNA makes proteins — is a flow of information that in eukaryotes encounters a physical barrier: the nuclear envelope, which encapsulates, organizes and protects the genome. Nuclear-pore complexes, embedded in the nuclear envelope, regulate the passage of molecules to and from the nucleus, including the poorly understood process of the export of RNAs from the nucleus. Recent imaging approaches focusing on single molecules have provided unexpected insight into this crucial step in the information flow. This review addresses the latest studies of RNA export and presents some models for how this complex process may work.
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A molecular beacon-based approach for live-cell imaging of RNA transcripts with minimal target engineering at the single-molecule level
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We apologize to those colleagues whose work, through space considerations, could not be discussed or cited in this review. This work has been supported by funds from the Kavli Foundation to D.G., National Institutes of Health grants GM86217 and GM84364 to R.H.S., and GM062427, RR022220 and GM071329 to M.R. We thank A. Joseph for critically reading the manuscript.
The authors declare no competing financial interests.
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Grünwald, D., Singer, R. & Rout, M. Nuclear export dynamics of RNA–protein complexes. Nature 475, 333–341 (2011). https://doi.org/10.1038/nature10318
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