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bioRxiv · 10.1101/097311

Microprocessor dynamics shows co- and post-transcriptional processingof pri-miRNAs

Louloupi, A.·Ntini, E.·Liz, J.·Orom, U. A.
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Abstract

miRNAs are small regulatory RNAs involved in the regulation of translation of target transcripts. miRNA biogenesis is a multi-step process starting with the cleavage of the primary miRNA transcript in the nucleus by the Microprocessor complex. Endogenous processing of pri-miRNAs is challenging to study and the in vivo kinetics of this process is not known. Here, we present a method for determining the processing kinetics of pri-miRNAs within intact cells over time using a pulse-chase approach to obtain nascent RNA within a 1-hour window after labeling with bromouridine. We show, that pri-miRNAs exhibit different processing kinetics ranging from fast over intermediate to slow processing and provide evidence that pri-miRNA processing can occur both co-transcriptionally and post-transcriptionally.

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Louloupi, A., Ntini, E., Liz, J., Orom, U. A.. 2016-12-29. Microprocessor dynamics shows co- and post-transcriptional processingof pri-miRNAs. https://doi.org/10.1101/097311

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