title: PRL1, an RNA-binding protein, positively regulates the accumulation of miRNAs and siRNAs in Arabidopsis.
abstract: The evolutionary conserved WD-40 protein PRL1 plays important roles in immunity and development. Here we show that PRL1 is required for the accumulation of microRNAs (miRNAs) and small interfering RNAs (siRNAs). PRL1 positively influences the processing of miRNA primary transcripts (pri-miRNAs) and double-stranded RNAs (dsRNAs). Furthermore, PRL1 interacts with the pri-miRNA processor, DCL1, and the dsRNA processors (DCL3 and DCL4). These results suggest that PRL1 may function as a general factor to promote the production of miRNAs and siRNAs. We also show that PRL1 is an RNA-binding protein and associates with pri-miRNAs in vivo. In addition, prl1 reduces pri-miRNA levels without affecting pri-miRNA transcription. These results suggest that PRL1 may stabilize pri-miRNAs and function as a co-factor to enhance DCL1 activity. We further reveal the genetic interaction of PRL1 with CDC5, which interacts with PRL1 and regulates transcription and processing of pri-miRNAs. Both miRNA and pri-miRNA levels are lower in cdc5 prl1 than those in either cdc5 or prl1. However, the processing efficiency of pri-miRNAs in cdc5 prl1 is similar to that in cdc5 and slightly lower than that in prl1. Based on these results, we propose that CDC5 and PRL1 cooperatively regulate pri-miRNA levels, which results in their synergistic effects on miRNA accumulation, while they function together as a complex to enhance DCL1 activity.
authors.affiliation: Center for Plant Science Innovation & School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America.
authors.forename: Shuxin
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Biotechnology Research Institute, Chinese Academy of Agricultural Sciences & Key Laboratory of Agricultural Genomics, Ministry of Agriculture, Beijing, China.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Center for Plant Science Innovation & School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, United States of America.
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000502:physiology*; D002352:Carrier Proteins / Q000502:physiology*; D018797:Cell Cycle Proteins / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D009687:Nuclear Proteins / Q000502:physiology*; D030821:Plants, Genetically Modified; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics; D020871:RNA Stability / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism
chemical_list: C102354:ATCDC5 protein, Arabidopsis; D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D035683:MicroRNAs; D009687:Nuclear Proteins; C492005:PRL1 protein, Arabidopsis; D034741:RNA, Small Interfering