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bioRxiv · 10.1101/2020.08.17.254193

Enhancers regulate polyadenylation site cleavage and control 3'UTR isoform expression

Kwon, B.·Patel, N. D.·Lee, S.-H.·Lee, J.·Ma, W.·Mayr, C.
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Abstract

Multi-UTR genes are widely transcribed but show cell type-specific 3'UTR isoform expression. As transcriptional enhancers regulate mRNA expression, we investigated if they also regulate mRNA isoform expression. Deletion of an endogenous enhancer of a multi-UTR gene did not impair transcript production but prevented a switch in 3'UTR isoform expression. Also, the same enhancers are able to increase transcript production in the context of single-UTR gene promoters, but they increase 3' end processing activity when paired with multi-UTR gene promoters. We show that transcription factors regulate processing activity of weak polyadenylation sites to control cell type-specific alternative 3'UTR isoform expression of widely expressed genes.

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Kwon, B., Patel, N. D., Lee, S.-H., Lee, J., Ma, W., Mayr, C.. 2020-08-17. Enhancers regulate polyadenylation site cleavage and control 3'UTR isoform expression. https://doi.org/10.1101/2020.08.17.254193

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