To the pore and through the pore: A story of mRNA export kinetics

Faculty of Medicine, Division of Experimental Medicine, McGill University, Montréal, Québec, Canada H3A 1A3.
Biochimica et Biophysica Acta (Impact Factor: 4.66). 02/2012; 1819(6):494-506. DOI: 10.1016/j.bbagrm.2012.02.011
Source: PubMed


The evolutionary 'decision' to store genetic information away from the place of protein synthesis, in a separate compartment, has forced eukaryotic cells to establish a system to transport mRNAs from the nucleus to the cytoplasm for translation. To ensure export to be fast and efficient, cells have evolved a complex molecular interplay that is tightly regulated. Over the last few decades, many of the individual players in this process have been described, starting with the composition of the nuclear pore complex to proteins that modulate co-transcriptional events required to prepare an mRNP for export to the cytoplasm. How the interplay between all the factors and processes results in the efficient and selective export of mRNAs from the nucleus and how the export process itself is executed within cells, however, is still not fully understood. Recent advances in using proteomic and single molecule microscopy approaches have provided important insights into the process and its kinetics. This review summarizes these recent advances and how they led to the current view on how cells orchestrate the export of mRNAs. This article is part of a Special Issue entitled: Nuclear Transport and RNA Processing.

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Available from: Marlene Oeffinger, Feb 11, 2014
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    • "The export of mRNAs from the nucleus to the cytoplasm is one of many steps along the gene expression pathway and is fundamental for mRNAs to meet with ribosomes for translation in the cytoplasm (Oeffinger and Zenklusen, 2012). Export to the cytoplasm occurs through the nuclear pore complex (NPC), a large macromolecular complex embedded in the nuclear membrane (Aitchison and Rout, 2012). "
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    • "NPCs consist of more than two dozen different proteins [132]. These nucleoporins form a channel and regulate the nucleocytoplasmic transport of various types of RNAs [133], and proteins [134]. The nuclear import and export of most proteins >40 KDa in size, including membrane "
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    • "Gating of active genes at NPCs is not strictly conserved . In mice and humans, for example, a number of developmentally regulated genes move away from the nuclear periphery upon induction, producing mRNA protein complexes that travel through the nucleoplasm to NPCs before export (see references in Egecioglu and Brickner 2011; Oeffinger and Zenklusen 2012). Nevertheless , components of the nuclear pore may still play significant roles in transcription. "
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