TY - JOUR T1 - Microprocessor dynamics shows co- and post-transcriptional processing of pri-miRNAs JF - bioRxiv DO - 10.1101/097311 SP - 097311 AU - Annita Louloupi AU - Evgenia Ntini AU - Julia Liz AU - Ulf Andersson Ørom Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/12/29/097311.abstract N2 - 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. ER -