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Ratnadiwakara M, Bahrudeen MN, Aikio E, Takabe P, Engel RM, Zahir Z, Jardé T, McMurrick PJ, Abud HE, Änkö ML. SRSF3 shapes the structure of miR-17-92 cluster RNA and promotes selective processing of miR-17 and miR-20a. EMBO Rep 2023:e56021. [PMID: 37306233 DOI: 10.15252/embr.202256021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 05/04/2023] [Accepted: 05/15/2023] [Indexed: 06/13/2023] Open
Abstract
MicroRNA (miRNA) biogenesis is tightly regulated to maintain distinct miRNA expression patterns. Almost half of mammalian miRNAs are generated from miRNA clusters, but this process is not well understood. We show here that Serine-arginine rich splicing factor 3 (SRSF3) controls the processing of miR-17-92 cluster miRNAs in pluripotent and cancer cells. SRSF3 binding to multiple CNNC motifs downstream of Drosha cleavage sites within miR-17-92 is required for the efficient processing of the cluster. SRSF3 depletion specifically compromises the processing of two paralog miRNAs, miR-17 and miR-20a. In addition to SRSF3 binding to the CNNC sites, the SRSF3 RS-domain is essential for miR-17-92 processing. SHAPE-MaP probing demonstrates that SRSF3 binding disrupts local and distant base pairing, resulting in global changes in miR-17-92 RNA structure. Our data suggest a model where SRSF3 binding, and potentially its RS-domain interactions, may facilitate an RNA structure that promotes miR-17-92 processing. SRSF3-mediated increase in miR-17/20a levels inhibits the cell cycle inhibitor p21, promoting self-renewal in normal and cancer cells. The SRSF3-miR-17-92-p21 pathway operates in colorectal cancer, linking SRSF3-mediated pri-miRNA processing and cancer pathogenesis.
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Affiliation(s)
- Madara Ratnadiwakara
- Hudson Institute of Medical Research, Clayton, Vic., Australia
- Department of Molecular and Translational Science, School of Clinical Sciences, Monash University, Clayton, Vic., Australia
| | | | - Erika Aikio
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Piia Takabe
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Rebekah M Engel
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Vic., Australia
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, Vic., Australia
- Department of Surgery, Cabrini Health, Cabrini Monash University, Malvern, Vic., Australia
| | - Zileena Zahir
- Hudson Institute of Medical Research, Clayton, Vic., Australia
- Department of Molecular and Translational Science, School of Clinical Sciences, Monash University, Clayton, Vic., Australia
| | - Thierry Jardé
- Hudson Institute of Medical Research, Clayton, Vic., Australia
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Vic., Australia
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, Vic., Australia
| | - Paul J McMurrick
- Department of Surgery, Cabrini Health, Cabrini Monash University, Malvern, Vic., Australia
| | - Helen E Abud
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Vic., Australia
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute, Clayton, Vic., Australia
| | - Minna-Liisa Änkö
- Hudson Institute of Medical Research, Clayton, Vic., Australia
- Department of Molecular and Translational Science, School of Clinical Sciences, Monash University, Clayton, Vic., Australia
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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2
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Mencia R, Gonzalo L, Tossolini I, Manavella PA. Keeping up with the miRNAs: current paradigms of the biogenesis pathway. J Exp Bot 2023; 74:2213-2227. [PMID: 35959860 DOI: 10.1093/jxb/erac322] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 07/26/2022] [Indexed: 06/06/2023]
Abstract
For many years we have studied the processes involved in producing miRNAs in plants and the numerous differences from their metazoan counterpart. A well-defined catalytic process, mostly carried out by the RNase III enzyme DICER-LIKE1 (DCL1), it was identified early after the discovery of RNAi and was followed by the isolation of a plethora of miRNA biogenesis cofactors. The production of miRNAs, which later are loaded in ARGONAUTE (AGO) proteins to perform their RNA silencing functions both within the cell and non-cell autonomously, appears to be a highly regulated and dynamic process. Many regulatory events during miRNA biogenesis require the action of specific proteins. However, in recent years, many post-transcriptional modifications, structural features, and coupling with other cellular processing emerged as critical elements controlling the production of miRNA and, thus, a plant's physiology. This review discusses new evidence that has changed the way we understand how miRNAs are produced in plants. We also provide an updated view of the miRNA biogenesis pathways, focusing on the gaps in our knowledge and the most compelling questions that remain open.
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Affiliation(s)
- Regina Mencia
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina
| | - Lucía Gonzalo
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina
| | - Ileana Tossolini
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina
| | - Pablo A Manavella
- Instituto de Agrobiotecnología del Litoral (CONICET-UNL), Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, 3000 Santa Fe, Argentina
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3
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Švab Ž, Braga L, Guarnaccia C, Labik I, Herzog J, Baralle M, Giacca M, Skoko N. High Throughput miRNA Screening Identifies miR-574-3p Hyperproductive Effect in CHO Cells. Biomolecules 2021; 11:1125. [PMID: 34439791 DOI: 10.3390/biom11081125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 07/11/2021] [Accepted: 07/23/2021] [Indexed: 12/21/2022] Open
Abstract
CHO is the cell line of choice for the manufacturing of many complex biotherapeutics. The constant upgrading of cell productivity is needed to meet the growing demand for these life-saving drugs. Manipulation of small non-coding RNAs—miRNAs—is a good alternative to a single gene knockdown approach due to their post-transcriptional regulation of entire cellular pathways without posing translational burden to the production cell. In this study, we performed a high-throughput screening of 2042-human miRNAs and identified several candidates able to increase cell-specific and overall production of Erythropoietin and Etanercept in CHO cells. Some of these human miRNAs have not been found in Chinese hamster cells and yet were still effective in them. We identified miR-574-3p as being able, when overexpressed in CHO cells, to improve overall productivity of Erythropoietin and Etanercept titers from 1.3 to up to 2-fold. In addition, we validated several targets of miR-574-3p and identified p300 as a main target of miR-574-3p in CHO cells. Furthermore, we demonstrated that stable CHO cell overexpressing miRNAs from endogenous CHO pri-miRNA sequences outperform the cells with human pri-miRNA sequences. Our findings highlight the importance of flanking genomic sequences, and their secondary structure features, on pri-miRNA processing offering a novel, cost-effective and fast strategy as a valuable tool for efficient miRNAs engineering in CHO cells.
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Kim K, Baek SC, Lee YY, Bastiaanssen C, Kim J, Kim H, Kim VN. A quantitative map of human primary microRNA processing sites. Mol Cell 2021; 81:3422-3439.e11. [PMID: 34320405 DOI: 10.1016/j.molcel.2021.07.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/26/2021] [Accepted: 07/02/2021] [Indexed: 12/11/2022]
Abstract
Maturation of canonical microRNA (miRNA) is initiated by DROSHA that cleaves the primary transcript (pri-miRNA). More than 1,800 miRNA loci are annotated in humans, but it remains largely unknown whether and at which sites pri-miRNAs are cleaved by DROSHA. Here, we performed in vitro processing on a full set of human pri-miRNAs (miRBase version 21) followed by sequencing. This comprehensive profiling enabled us to classify miRNAs on the basis of DROSHA dependence and map their cleavage sites with respective processing efficiency measures. Only 758 pri-miRNAs are confidently processed by DROSHA, while the majority may be non-canonical or false entries. Analyses of the DROSHA-dependent pri-miRNAs show key cis-elements for processing. We observe widespread alternative processing and unproductive cleavage events such as "nick" or "inverse" processing. SRSF3 is a broad-acting auxiliary factor modulating alternative processing and suppressing unproductive processing. The profiling data and methods developed in this study will allow systematic analyses of miRNA regulation.
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Affiliation(s)
- Kijun Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - S Chan Baek
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Young-Yoon Lee
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Carolien Bastiaanssen
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Jeesoo Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Haedong Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea.
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Abstract
MicroRNAs (miRNAs) are essential non-coding riboregulators of gene expression in plants and animals. In plants, miRNAs guide their effector protein named ARGONAUTE (AGO) to find target RNAs for gene silencing through target RNA cleavage or translational inhibition. miRNAs are derived from primary miRNA transcripts (pri-miRNAs), most of which are transcribed by the DNA-dependent RNA polymerase II. In plants, an RNase III enzyme DICER-LIKE1-containing complex processes pri-miRNAs in the nucleus into miRNAs. To ensure proper function of miRNAs, plants use multiple mechanisms to control miRNA accumulation. On one hand, pri-miRNA levels are controlled through transcription and stability. On the other hand, the activities of the DCL1 complex are regulated by many protein factors at transcriptional, post-transcriptional and post-translational levels. Notably, recent studies reveal that pri-miRNA structure/sequence features and modifications also play important roles in miRNA biogenesis. In this review, we summarize recent progresses on the mechanisms regulating miRNA biogenesis.
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Affiliation(s)
- Mu Li
- School of Biological Sciences & Center for Plant Science Innovation University of Nebraska-Lincoln, Lincoln, Nebraska USA
| | - Bin Yu
- School of Biological Sciences & Center for Plant Science Innovation University of Nebraska-Lincoln, Lincoln, Nebraska USA
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Nogami M, Miyamoto K, Hayakawa-Yano Y, Nakanishi A, Yano M, Okano H. DGCR8-dependent efficient pri-miRNA processing of human pri-miR-9-2. J Biol Chem 2021; 296:100409. [PMID: 33581109 PMCID: PMC7995608 DOI: 10.1016/j.jbc.2021.100409] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 02/03/2021] [Accepted: 02/09/2021] [Indexed: 12/22/2022] Open
Abstract
Microprocessor complex, including DiGeorge syndrome critical region gene 8 (DGCR8) and DROSHA, recognizes and cleaves primary transcripts of microRNAs (pri-miRNAs) in the maturation of canonical miRNAs. The study of DGCR8 haploinsufficiency reveals that the efficiency of this activity varies for different miRNA species. It is thought that this variation might be associated with the risk of schizophrenia with 22q11 deletion syndrome caused by disruption of the DGCR8 gene. However, the underlying mechanism for varying action of DGCR8 with each miRNA remains largely unknown. Here, we used in vivo monitoring to measure the efficiency of DGCR8-dependent microprocessor activity in cultured cells. We confirmed that this system recapitulates the microprocessor activity of endogenous pri-miRNA with expression of a ratiometric fluorescence reporter. Using this system, we detected mir-9-2 as one of the most efficient targets. We also identified a novel DGCR8-responsive RNA element, which is highly conserved among mammalian species and could be regulated at the epi-transcriptome (RNA modification) level. This unique feature between DGCR8 and pri-miR-9-2 processing may suggest a link to the risk of schizophrenia.
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Affiliation(s)
- Masahiro Nogami
- Innovative Biology Laboratories, Neuroscience Drug Discovery Unit, Research, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan; Shonan Incubation Laboratories, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan.
| | - Kazumasa Miyamoto
- Drug Safety Research Laboratories, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Yoshika Hayakawa-Yano
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Atsushi Nakanishi
- Shonan Incubation Laboratories, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan; Regenerative Medicine Unit, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa, Japan
| | - Masato Yano
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan; Department of Physiology, School of Medicine, Keio University, Tokyo, Japan.
| | - Hideyuki Okano
- Department of Physiology, School of Medicine, Keio University, Tokyo, Japan
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Hutter K, Lohmüller M, Jukic A, Eichin F, Avci S, Labi V, Szabo TG, Hoser SM, Hüttenhofer A, Villunger A, Herzog S. SAFB2 Enables the Processing of Suboptimal Stem-Loop Structures in Clustered Primary miRNA Transcripts. Mol Cell 2020; 78:876-889.e6. [PMID: 32502422 DOI: 10.1016/j.molcel.2020.05.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/24/2020] [Accepted: 05/08/2020] [Indexed: 12/16/2022]
Abstract
Many microRNAs (miRNAs) are generated from primary transcripts containing multiple clustered stem-loop structures that are thought to be recognized and cleaved by the Microprocessor complex as independent units. Here, we uncover an unexpected mode of processing of the bicistronic miR-15a-16-1 cluster. We find that the primary miR-15a stem-loop is not processed on its own but that the presence of the neighboring primary miR-16-1 stem-loop on the same transcript can compensate for this deficiency in cis. Using a CRISPR/Cas9 screen, we identify SAFB2 (scaffold attachment factor B2) as an essential co-factor in this miR-16-1-assisted pri-miR-15 cleavage and describe SAFB2 as an accessory protein of the Microprocessor. Notably, SAFB2-mediated cleavage expands to other clustered pri-miRNAs, indicating a general mechanism. Together, our study reveals an unrecognized function of SAFB2 in miRNA processing and suggests a scenario in which SAFB2 enables the binding and processing of suboptimal Microprocessor substrates in clustered primary miRNA transcripts.
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Affiliation(s)
- Katharina Hutter
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Michael Lohmüller
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Almina Jukic
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Felix Eichin
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Seymen Avci
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Verena Labi
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Tamas G Szabo
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Simon M Hoser
- Institute for Genomics and RNomics, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Alexander Hüttenhofer
- Institute for Genomics and RNomics, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria
| | - Andreas Villunger
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria; CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090 Vienna, Austria; Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, 1090 Vienna, Austria
| | - Sebastian Herzog
- Institute of Developmental Immunology, Biocenter, Medical University Innsbruck, 6020 Innsbruck, Austria.
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Fang W, Bartel DP. MicroRNA Clustering Assists Processing of Suboptimal MicroRNA Hairpins through the Action of the ERH Protein. Mol Cell 2020; 78:289-302.e6. [PMID: 32302541 PMCID: PMC7243034 DOI: 10.1016/j.molcel.2020.01.026] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 01/02/2020] [Accepted: 01/27/2020] [Indexed: 02/07/2023]
Abstract
Microprocessor initiates the processing of microRNAs (miRNAs) from the hairpin regions of primary transcripts (pri-miRNAs). Pri-miRNAs often contain multiple miRNA hairpins, and this clustered arrangement can assist in the processing of otherwise defective hairpins. We find that miR-451, which derives from a hairpin with a suboptimal terminal loop and a suboptimal stem length, accumulates to 40-fold higher levels when clustered with a helper hairpin. This phenomenon tolerates changes in hairpin order, linker lengths, and the identities of the helper hairpin, the recipient hairpin, the linker-sequence, and the RNA polymerase that transcribes the hairpins. It can act reciprocally and need not occur co-transcriptionally. It requires Microprocessor recognition of the helper hairpin and linkage of the two hairpins, yet predominantly manifests after helper-hairpin processing. It also requires enhancer of rudimentary homolog (ERH), which copurifies with Microprocessor and can dimerize and interact with other proteins that can dimerize, suggesting a model in which one Microprocessor recruits another Microprocessor.
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Affiliation(s)
- Wenwen Fang
- Howard Hughes Medical Institute, Cambridge, MA 02142, USA; Whitehead Institute of Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - David P Bartel
- Howard Hughes Medical Institute, Cambridge, MA 02142, USA; Whitehead Institute of Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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9
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Abstract
RNA G-Quadruplexes (G4) have been shown to possess many biological functions, including the regulation of microRNA (miRNA) biogenesis and function. However, their impact on pri-miRNA processing remains unknown. We identified G4 located near the Drosha cleavage site in three distinct pri-miRNAs: pri-mir200c, pri-mir451a, and pri-mir497. The folding of the potential G4 motifs was determined in solution. Subsequently, mutations disrupting G4 folding led to important changes in the mature miRNAs levels in cells. Moreover, using small antisense oligonucleotides binding to the pri-miRNA, it was possible to modulate, either positively or negatively, the mature miRNA levels. Together, these data demonstrate that G4 motifs could contribute to the regulation of pri-mRNA processing, a novel role for G4. Considering that bio-informatics screening indicates that between 9% and 50% of all pri-miRNAs contain a putative G4, these structures possess interesting potential as future therapeutic targets.
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Affiliation(s)
- Samuel G Rouleau
- a Département de Biochimie, Pavillon de Recherche Appliquée sur le Cancer , Université de , Sherbrooke, 3201 Jean-Mignault, Sherbrooke , Québec , Canada
| | - Jean-Michel Garant
- a Département de Biochimie, Pavillon de Recherche Appliquée sur le Cancer , Université de , Sherbrooke, 3201 Jean-Mignault, Sherbrooke , Québec , Canada
| | - François Bolduc
- a Département de Biochimie, Pavillon de Recherche Appliquée sur le Cancer , Université de , Sherbrooke, 3201 Jean-Mignault, Sherbrooke , Québec , Canada
| | - Martin Bisaillon
- a Département de Biochimie, Pavillon de Recherche Appliquée sur le Cancer , Université de , Sherbrooke, 3201 Jean-Mignault, Sherbrooke , Québec , Canada
| | - Jean-Pierre Perreault
- a Département de Biochimie, Pavillon de Recherche Appliquée sur le Cancer , Université de , Sherbrooke, 3201 Jean-Mignault, Sherbrooke , Québec , Canada
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10
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Zhang Z, Guo X, Ge C, Ma Z, Jiang M, Li T, Koiwa H, Yang SW, Zhang X. KETCH1 imports HYL1 to nucleus for miRNA biogenesis in Arabidopsis. Proc Natl Acad Sci U S A 2017; 114:4011-4016. [PMID: 28348234 PMCID: PMC5393240 DOI: 10.1073/pnas.1619755114] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
MicroRNA (miRNA) is processed from primary transcripts with hairpin structures (pri-miRNAs) by microprocessors in the nucleus. How cytoplasmic-borne microprocessor components are transported into the nucleus to fulfill their functions remains poorly understood. Here, we report KETCH1 (karyopherin enabling the transport of the cytoplasmic HYL1) as a partner of hyponastic leaves 1 (HYL1) protein, a core component of microprocessor in Arabidopsis and functional counterpart of DGCR8/Pasha in animals. Null mutation of ketch1 is embryonic-lethal, whereas knockdown mutation of ketch1 caused morphological defects, reminiscent of mutants in the miRNA pathway. ketch1 knockdown mutation also substantially reduced miRNA accumulation, but did not alter nuclear-cytoplasmic shuttling of miRNAs. Rather, the mutation significantly reduced nuclear portion of HYL1 protein and correspondingly compromised the pri-miRNA processing in the nucleus. We propose that KETCH1 transports HYL1 from the cytoplasm to the nucleus to constitute functional microprocessor in Arabidopsis This study provides insight into the largely unknown nuclear-cytoplasmic trafficking process of miRNA biogenesis components through eukaryotes.
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Affiliation(s)
- Zhonghui Zhang
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843
- Guangdong Provincial Key Laboratory of Biotechnology for Plant Development, School of Life Science, South China Normal University, Guangzhou 510631, China
| | - Xinwei Guo
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Chunxiao Ge
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843
| | - Zeyang Ma
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843
| | - Mengqiu Jiang
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843
| | - Tianhong Li
- College of Horticulture, China Agricultural University, Beijing 100193, China
| | - Hisashi Koiwa
- Department of Horticultural Sciences, Texas A&M University, College Station, TX 77843
| | - Seong Wook Yang
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Republic of Korea
| | - Xiuren Zhang
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, College Station, TX 77843;
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11
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Abstract
MicroRNAs (miRNAs) are a class of small non-coding RNAs (small RNAs) that are 20-24nt in length and predominantly repress gene expression at post-transcriptional levels. They regulate many biological processes including development, metabolism and physiology. Numerous studies have revealed that the steady-state levels of miRNA are under sophisticated control to ensure their proper function. In this review, we summarize recent advances on regulation of miRNA processing and stability in plants.
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Affiliation(s)
| | - Bin Yu
- Correspondence to: Bin Yu,
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