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bioRxiv · 10.1101/2023.04.03.535409

The DEAD-box helicase RCF1 plays roles in miRNA biogenesis and RNA splicing in Arabidopsis

Xu, C.·Zhang, Z.·He, J.·Bai, Y.·Liu, L.·Tang, J.·Tang, G.·Chen, X.·Mo, B.
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Abstract

RCF1 is a highly conserved DEAD-box helicase found in yeast, plants and mammals. Studies about the functions of RCF1 in plants are limited. Here we uncovered the functions of RCF1 in Arabidopsis thaliana as a player in pri-miRNA processing and splicing, as well as in pre-mRNA splicing. A mutant with miRNA biogenesis defects was isolated and the defect was traced to a recessive point mutation in RCF1 (rcf1-4). We show that RCF1 promotes D-body formation and facilitates the interaction between pri-miRNAs and HYL1. Finally, we show that intron-containing pri-miRNAs and pre-mRNAs exhibit a global splicing defect in rcf1-4. Together, this work uncovers roles for RCF1 in miRNA biogenesis and RNA splicing in Arabidopsis. One-sentence summaryRCF1 promotes not only the processing of pri-miRNAs, but also the splicing of intron-containing pri-miRNAs, therefore promotes miRNA biogenesis.

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Xu, C., Zhang, Z., He, J., Bai, Y., Liu, L., Tang, J., Tang, G., Chen, X., Mo, B.. 2023-04-04. The DEAD-box helicase RCF1 plays roles in miRNA biogenesis and RNA splicing in Arabidopsis. https://doi.org/10.1101/2023.04.03.535409

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