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A new view of mRNA export: Separating the wheat from the chaff

Nature Cell Biology volume 3, pages E201–E204 (2001)Cite this article

Current models for the export of messenger RNA share the notion that the highly abundant class of nuclear RNA-binding proteins — the hnRNP proteins — have a key role in exporting mRNA. But recent studies have led to a new understanding of several non-hnRNP proteins, including SR proteins and the conserved mRNA export factor ALY, which are recruited to the mRNA during pre-mRNA splicing. These studies, together with older work on hnRNP particles and assembly of the spliceosome, lead us to a new view of mRNA export. In our model, the non-hnRNP factors form a splicing-dependent mRNP complex that specifically targets mature mRNA for export, while hnRNP proteins retain introns in the nucleus. A machinery that is conserved between yeast and higher eukaryotes functions to export the mRNA.

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Figure 1: New model for mRNA export.

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Acknowledgements

We thank M. Luo, Z. Zhou and the other members of the Reed laboratory for comments and discussions. We also thank E. Hurt and K. Strasser for discussions.

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  1. Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, 02115, Massachusetts, USA

    Robin Reed & Keith Magni

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Reed, R., Magni, K. A new view of mRNA export: Separating the wheat from the chaff. Nat Cell Biol 3, E201–E204 (2001). https://doi.org/10.1038/ncb0901-e201

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