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bioRxiv · 10.1101/149245

Splicing-dependent NMD requires Prp17 in Saccharomyces cerevisiae

Wen, J.·Marzi, L.·Wang, J.·Ye, J.·Brogna, S.
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Abstract

Nonsense mediated mRNA decay (NMD) is regarded as the function of a specialized cytoplasmic translation-coupled mRNA decay pathway in eukaryotes, however, whether a premature translation termination codon (PTC) will lead to NMD often depends on splicing a downstream intron in the nucleus. Deposition of the exon junction complex (EJC) on mRNA is understood to mediate such splicing-dependent NMD in mammalian cells. The budding yeast, Saccharomyces cerevisiae, which has introns in only 5% of its genes, characteristically at the start of the coding region, and lacks proteins essential for EJC assembly, is not expected to undergo splicing-dependent NMD. However, we found that the presence of an intron near a PTC can also enhance NMD in this organism, regardless of whether it is downstream or upstream. These data provide evidence for a hitherto unsuspected EJC-independent mechanism linking translation and pre-mRNA in S. cerevisiae.

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Wen, J., Marzi, L., Wang, J., Ye, J., Brogna, S.. 2017-06-12. Splicing-dependent NMD requires Prp17 in Saccharomyces cerevisiae. https://doi.org/10.1101/149245

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