1
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Petrić Howe M, Crerar H, Neeves J, Harley J, Tyzack GE, Klein P, Ramos A, Patani R, Luisier R. Physiological intron retaining transcripts in the cytoplasm abound during human motor neurogenesis. Genome Res 2022; 32:1808-1825. [PMID: 36180233 PMCID: PMC9712626 DOI: 10.1101/gr.276898.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 09/16/2022] [Indexed: 11/24/2022]
Abstract
Intron retention (IR) is now recognized as a dominant splicing event during motor neuron (MN) development; however, the role and regulation of intron-retaining transcripts (IRTs) localized to the cytoplasm remain particularly understudied. Here we show that IR is a physiological process that is spatiotemporally regulated during MN lineage restriction and that IRTs in the cytoplasm are detected in as many as 13% (n = 2297) of the genes expressed during this process. We identify a major class of cytoplasmic IRTs that are not associated with reduced expression of their own genes but instead show a high capacity for RNA-binding protein and miRNA occupancy. Finally, we show that ALS-causing VCP mutations lead to a selective increase in cytoplasmic abundance of this particular class of IRTs, which in turn temporally coincides with an increase in the nuclear expression level of predicted miRNA target genes. Altogether, our study identifies a previously unrecognized class of cytoplasmic intronic sequences with potential regulatory function beyond gene expression.
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Affiliation(s)
- Marija Petrić Howe
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Hamish Crerar
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Jacob Neeves
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Jasmine Harley
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Giulia E Tyzack
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Pierre Klein
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Research Department of Structural and Molecular Biology, University College London, London WC1E 6XA, United Kingdom
| | - Andres Ramos
- Research Department of Structural and Molecular Biology, University College London, London WC1E 6XA, United Kingdom
| | - Rickie Patani
- The Francis Crick Institute, London NW1 1AT, United Kingdom
- Department of Molecular Neuroscience, UCL Institute of Neurology, London WC1N 3AR, United Kingdom
| | - Raphaëlle Luisier
- Idiap Research Institute, Genomics and Health Informatics, CH-1920 Martigny, Switzerland
- SIB Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
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2
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Abstract
Coronaviruses (CoVs) are emergent pathogens that may cause life-threatening respiratory diseases in humans. Understanding of CoV-host interactions may help to identify novel therapeutic targets. MOV10 is an RNA helicase involved in different steps of cellular RNA metabolism. Both MOV10 antiviral and proviral activities have been described in a limited number of viruses, but this protein has not been previously associated with CoVs. We found that during Middle East respiratory syndrome coronavirus (MERS-CoV) infection, MOV10 aggregated in cytoplasmic structures colocalizing with viral nucleocapsid (N) protein. MOV10-N interaction was confirmed by endogenous MOV10 coimmunoprecipitation, and the presence of other cellular proteins was also detected in MOV10 complexes. MOV10 silencing significantly increased both N protein accumulation and virus titer, with no changes in the accumulation of viral RNAs. Moreover, MOV10 overexpression caused a 10-fold decrease in viral titers. These data indicated that MOV10 has antiviral activity during MERS-CoV infection. We postulated that this activity could be mediated by viral RNA sequestration, and in fact, RNA immunoprecipitation data showed the presence of viral RNAs in the MOV10 cytoplasmic complexes. Expression of wild-type MOV10 or of a MOV10 mutant without helicase activity in MOV10 knockout cell lines, developed by CRISPR-Cas technology, indicated that the helicase activity of MOV10 was required for its antiviral effect. Interestingly MOV10-N interaction was conserved in other mildly or highly pathogenic human CoVs, including the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), although MOV10 antiviral activity was found only in highly pathogenic CoVs, suggesting a potential role of MOV10 in the modulation of human CoVs pathogenesis.
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3
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Park J, Seo JW, Ahn N, Park S, Hwang J, Nam JW. UPF1/SMG7-dependent microRNA-mediated gene regulation. Nat Commun 2019; 10:4181. [PMID: 31519907 PMCID: PMC6744440 DOI: 10.1038/s41467-019-12123-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 08/20/2019] [Indexed: 12/16/2022] Open
Abstract
The stability and quality of metazoan mRNAs are under microRNA (miRNA)-mediated and nonsense-mediated control. Although UPF1, a core mediator of nonsense-mediated mRNA decay (NMD), mediates the decay of target mRNA in a 3′UTR-length-dependent manner, the detailed mechanism remains unclear. Here, we suggest that 3′UTR-length-dependent mRNA decay is not mediated by nonsense mRNAs but rather by miRNAs that downregulate target mRNAs via Ago-associated UPF1/SMG7. Global analyses of mRNAs in response to UPF1 RNA interference in miRNA-deficient cells reveal that 3′UTR-length-dependent mRNA decay by UPF1 requires canonical miRNA targeting. The destabilization of miRNA targets is accomplished by the combination of Ago2 and UPF1/SMG7, which may recruit the CCR4-NOT deadenylase complex. Indeed, loss of the SMG7-deadenylase complex interaction increases the levels of transcripts regulated by UPF1-SMG7. This UPF1/SMG7-dependent miRNA-mediated mRNA decay pathway may enable miRNA targeting to become more predictable and expand the miRNA-mRNA regulatory network. UPF1 mediates the decay of target mRNA in a 3′ untranslated region (UTR)-length-dependent manner. Here the authors reveal that the 3′UTR-length-dependent regulation of UPF1-dependent mRNA decay occurs through EJC-independent but miRNA-dependent regulation.
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Affiliation(s)
- Jungyun Park
- Graduate School for Biomedical Science & Engineering, Hanyang University, Seoul, Republic of Korea
| | - Jwa-Won Seo
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - Narae Ahn
- Graduate School for Biomedical Science & Engineering, Hanyang University, Seoul, Republic of Korea
| | - Seokju Park
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, Republic of Korea
| | - Jungwook Hwang
- Graduate School for Biomedical Science & Engineering, Hanyang University, Seoul, Republic of Korea. .,Department of Medical Genetics, College of Medicine, Hanyang University, Seoul, Republic of Korea.
| | - Jin-Wu Nam
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul, Republic of Korea. .,Research Institute for Convergence of Basic Sciences, Hanyang University, Seoul, Republic of Korea.
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4
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Díaz-Muñoz MD, Turner M. Uncovering the Role of RNA-Binding Proteins in Gene Expression in the Immune System. Front Immunol 2018; 9:1094. [PMID: 29875770 PMCID: PMC5974052 DOI: 10.3389/fimmu.2018.01094] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/02/2018] [Indexed: 12/29/2022] Open
Abstract
Fighting external pathogens requires an ever-changing immune system that relies on tight regulation of gene expression. Transcriptional control is the first step to build efficient responses while preventing immunodeficiencies and autoimmunity. Post-transcriptional regulation of RNA editing, location, stability, and translation are the other key steps for final gene expression, and they are all controlled by RNA-binding proteins (RBPs). Nowadays we have a deep understanding of how transcription factors control the immune system but recent evidences suggest that post-transcriptional regulation by RBPs is equally important for both development and activation of immune responses. Here, we review current knowledge about how post-transcriptional control by RBPs shapes our immune system and discuss the perspective of RBPs being the key players of a hidden immune cell epitranscriptome.
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Affiliation(s)
- Manuel D Díaz-Muñoz
- Centre de Physiopathologie Toulouse-Purpan, INSERM UMR1043/CNRS U5282, Toulouse, France
| | - Martin Turner
- Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, United Kingdom
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5
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Kong SY, Kim W, Lee HR, Kim HJ. The histone demethylase KDM5A is required for the repression of astrocytogenesis and regulated by the translational machinery in neural progenitor cells. FASEB J 2018; 32:1108-1119. [PMID: 29212818 PMCID: PMC6266631 DOI: 10.1096/fj.201700780r] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 11/27/2017] [Indexed: 01/20/2023]
Abstract
Histone demethylases are known to play important roles in the determination of the fate of stem cells and in cancer progression. In this study, we show that the lysine 4 of histone H3 (H3K4), lysine-specific demethylase 5A (KDM5A) is essential for the repression of astrocyte differentiation in neural progenitor cells (NPCs), and its expression is regulated by translational machinery. Knockdown of KDM5A in NPCs increased astrocytogenesis, and conversely, KDM5A overexpression reduced the transcriptional activity of the Gfap promoter. Induction of astrocytogenesis by ciliary neurotrophic factor (CNTF) or small interfering RNA-induced knockdown of KDM5A decreased KDM5A recruitment to the Gfap promoter and increased H3K4 methylation. The transcript level of Kdm5a was high, whereas KDM5A protein level was low in CNTF induced astrocytes. During astroglial differentiation, translational activity indicated by the phosphorylation of eukaryotic translation initiation factor (eIF)4E was decreased. Treatment of NPCs with the cercosporamide, a MAPK-interacting kinases inhibitor, reduced eIF4E phosphorylation and KDM5A protein expression, increased GFAP levels, and enhanced astrocytogenesis. These data suggest that KDM5A is a key regulator that maintains NPCs in an undifferentiated state by repressing astrocytogenesis and that its expression is translationally controlled during astrocyte differentiation. Thus, KDM5A is a promising target for the modulation of NPC fate.-Kong, S.-Y., Kim, W., Lee, H.-R., Kim, H.-J. The histone demethylase KDM5A is required for the repression of astrocytogenesis and regulated by the translational machinery in neural progenitor cells.
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Affiliation(s)
- Sun-Young Kong
- Laboratory of Molecular and Stem Cell Pharmacology, College of Pharmacy,
Chung-Ang University, Seoul, South Korea
| | - Woosuk Kim
- Laboratory of Molecular and Stem Cell Pharmacology, College of Pharmacy,
Chung-Ang University, Seoul, South Korea
| | - Ha-Rim Lee
- Laboratory of Molecular and Stem Cell Pharmacology, College of Pharmacy,
Chung-Ang University, Seoul, South Korea
| | - Hyun-Jung Kim
- Laboratory of Molecular and Stem Cell Pharmacology, College of Pharmacy,
Chung-Ang University, Seoul, South Korea
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6
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Gulay SP, Bista S, Varshney A, Kirmizialtin S, Sanbonmatsu KY, Dinman JD. Tracking fluctuation hotspots on the yeast ribosome through the elongation cycle. Nucleic Acids Res 2017; 45:4958-4971. [PMID: 28334755 PMCID: PMC5416885 DOI: 10.1093/nar/gkx112] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 02/06/2017] [Indexed: 11/15/2022] Open
Abstract
Chemical modification was used to quantitatively determine the flexibility of nearly the entire rRNA component of the yeast ribosome through 8 discrete stages of translational elongation, revealing novel observations at the gross and fine-scales. These include (i) the bulk transfer of energy through the intersubunit bridges from the large to the small subunit after peptidyltransfer, (ii) differences in the interaction of the sarcin ricin loop with the two elongation factors and (iii) networked information exchange pathways that may functionally facilitate intra- and intersubunit coordination, including the 5.8S rRNA. These analyses reveal hot spots of fluctuations that set the stage for large-scale conformational changes essential for translocation and enable the first molecular dynamics simulation of an 80S complex. Comprehensive datasets of rRNA base flexibilities provide a unique resource to the structural biology community that can be computationally mined to complement ongoing research toward the goal of understanding the dynamic ribosome.
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Affiliation(s)
- Suna P Gulay
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
| | - Sujal Bista
- Department of Computer Science, University of Maryland, College Park, MD 20742, USA
| | - Amitabh Varshney
- Department of Computer Science, University of Maryland, College Park, MD 20742, USA
| | - Serdal Kirmizialtin
- Chemistry Program, New York University Abu Dhabi, Abu Dhabi, UAE.,The New Mexico Consortium, Los Alamos, NM 87544, USA
| | - Karissa Y Sanbonmatsu
- The New Mexico Consortium, Los Alamos, NM 87544, USA.,Theoretical Biology and Biophysics, Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA
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7
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Elbarbary RA, Miyoshi K, Hedaya O, Myers JR, Maquat LE. UPF1 helicase promotes TSN-mediated miRNA decay. Genes Dev 2017; 31:1483-1493. [PMID: 28827400 PMCID: PMC5588929 DOI: 10.1101/gad.303537.117] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 07/24/2017] [Indexed: 12/22/2022]
Abstract
While microRNAs (miRNAs) regulate the vast majority of protein-encoding transcripts, little is known about how miRNAs themselves are degraded. We recently described Tudor-staphylococcal/micrococcal-like nuclease (TSN)-mediated miRNA decay (TumiD) as a cellular pathway in which the nuclease TSN promotes the decay of miRNAs that contain CA and/or UA dinucleotides. While TSN-mediated degradation of either protein-free or AGO2-loaded miRNAs does not require the ATP-dependent RNA helicase UPF1 in vitro, we report here that cellular TumiD requires UPF1. Results from experiments using AGO2-loaded miRNAs in duplex with target mRNAs indicate that UPF1 can dissociate miRNAs from their mRNA targets, making the miRNAs susceptible to TumiD. miR-seq (deep sequencing of miRNAs) data reveal that the degradation of ∼50% of candidate TumiD targets in T24 human urinary bladder cancer cells is augmented by UPF1. We illustrate the physiological relevance by demonstrating that UPF1-augmented TumiD promotes the invasion of T24 cells in part by degrading anti-invasive miRNAs so as to up-regulate the expression of proinvasive proteins.
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Affiliation(s)
- Reyad A Elbarbary
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Keita Miyoshi
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Omar Hedaya
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
| | - Jason R Myers
- Genomics Research Center, University of Rochester, Rochester, New York 14642, USA
| | - Lynne E Maquat
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
- Center for RNA Biology, University of Rochester, Rochester, New York 14642, USA
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8
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Paces J, Nic M, Novotny T, Svoboda P. Literature review of baseline information to support the risk assessment of RNAi‐based GM plants. ACTA ACUST UNITED AC 2017. [PMCID: PMC7163844 DOI: 10.2903/sp.efsa.2017.en-1246] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jan Paces
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic (IMG)
| | | | | | - Petr Svoboda
- Institute of Molecular Genetics of the Academy of Sciences of the Czech Republic (IMG)
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9
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Zhai L, Wang L, Teng F, Zhou L, Zhang W, Xiao J, Liu Y, Deng W. Argonaute and Argonaute-Bound Small RNAs in Stem Cells. Int J Mol Sci 2016; 17:208. [PMID: 26861290 PMCID: PMC4783940 DOI: 10.3390/ijms17020208] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 01/28/2016] [Accepted: 02/01/2016] [Indexed: 12/15/2022] Open
Abstract
Small RNAs are essential for a variety of cellular functions. Argonaute (AGO) proteins are associated with all of the different classes of small RNAs, and are indispensable in small RNA-mediated regulatory pathways. AGO proteins have been identified in various types of stem cells in diverse species from plants and animals. This review article highlights recent progress on how AGO proteins and AGO-bound small RNAs regulate the self-renewal and differentiation of distinct stem cell types, including pluripotent, germline, somatic, and cancer stem cells.
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Affiliation(s)
- Lihong Zhai
- Medical College, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China.
| | - Lin Wang
- Xiangyang Oral Hospital, Xiangyang 441003, Hubei, China.
| | - Feng Teng
- Medical College, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China.
| | - Lanting Zhou
- Medical College, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China.
| | - Wenjing Zhang
- Medical College, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China.
| | - Juan Xiao
- Medical College, Hubei University of Arts and Science, Xiangyang 441053, Hubei, China.
| | - Ying Liu
- Department of Neurosurgery, Medical School, the Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
- Center for Stem Cell and Regenerative Medicine, the Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
| | - Wenbin Deng
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95817, USA.
- Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children, Sacramento, CA 95817, USA.
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10
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Bajan S, Hutvagner G. Regulation of miRNA processing and miRNA mediated gene repression in cancer. Microrna 2015; 3:10-7. [PMID: 25069508 PMCID: PMC4260356 DOI: 10.2174/2211536602666140110234046] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 12/13/2013] [Accepted: 12/20/2013] [Indexed: 12/19/2022]
Abstract
The majority of human protein-coding genes are predicted to be targets of miRNA-mediated post-transcriptional regulation. The widespread influence of miRNAs is illustrated by their essential roles in all biological processes. Regulated miRNA expression is essential for maintaining cellular differentiation; therefore alterations in miRNA expression patterns are associated with several diseases, including various cancers. High-throughput sequencing technologies revealed low level expressing miRNA isoforms, termed isomiRs. IsomiRs may differ in sequence, length, target preference and expression patterns from their parental miRNA and can arise from differences in miRNA biosynthesis, RNA editing, or SNPs inherent to the miRNA gene. The association between isomiR expression and disease progression is largely unknown. Misregulated miRNA expression is thought to contribute to the formation and/or progression of cancer. However, due to the diversity of targeted transcripts, miRNAs can function as both tumor-suppressor genes and oncogenes as defined by cellular context. Despite this, miRNA profiling studies concluded that the differential expression of particular miRNAs in diseased tissue could aid the diagnosis and treatment of some cancers.
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Affiliation(s)
| | - Gyorgy Hutvagner
- Correspondence: Faculty of Engineering and Information Technology, Centre of Health Technology, University of Technology Sydney, Sydney, Australia
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11
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Fischer-Kešo R, Breuninger S, Hofmann S, Henn M, Röhrig T, Ströbel P, Stoecklin G, Hofmann I. Plakophilins 1 and 3 bind to FXR1 and thereby influence the mRNA stability of desmosomal proteins. Mol Cell Biol 2014; 34:4244-56. [PMID: 25225333 PMCID: PMC4248750 DOI: 10.1128/mcb.00766-14] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 06/28/2014] [Accepted: 09/11/2014] [Indexed: 12/21/2022] Open
Abstract
Plakophilins 1 and 3 (PKP1/3) are members of the arm repeat family of catenin proteins and serve as structural components of desmosomes, which are important for cell-cell-adhesion. In addition, PKP1/3 occur as soluble proteins outside desmosomes, yet their role in the cytoplasm is not known. We found that cytoplasmic PKP1/3 coprecipitated with the RNA-binding proteins FXR1, G3BP, PABPC1, and UPF1, and these PKP1/3 complexes also comprised desmoplakin and PKP2 mRNAs. Moreover, we showed that the interaction of PKP1/3 with G3BP, PABPC1, and UPF1 but not with FXR1 was RNase sensitive. To address the cytoplasmic function of PKP1/3, we performed gain-and-loss-of-function studies. Both PKP1 and PKP3 knockdown cell lines showed reduced protein and mRNA levels for desmoplakin and PKP2. Whereas global rates of translation were unaffected, desmoplakin and PKP2 mRNA were destabilized. Furthermore, binding of PKP1/3 to FXR1 was RNA independent, and both PKP3 and FXR1 stabilized PKP2 mRNA. Our results demonstrate that cytoplasmic PKP1/3 are components of mRNA ribonucleoprotein particles and act as posttranscriptional regulators of gene expression.
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Affiliation(s)
- Regina Fischer-Kešo
- Division of Vascular Oncology and Metastasis, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany Department of Vascular Biology and Tumor Angiogenesis, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Sonja Breuninger
- Division of Vascular Oncology and Metastasis, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany Department of Vascular Biology and Tumor Angiogenesis, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Sarah Hofmann
- Helmholtz Junior Research Group, Posttranscriptional Control of Gene Expression, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany Center for Molecular Biology at the Heidelberg University, Heidelberg, Germany
| | - Manuela Henn
- Department of Vascular Biology and Tumor Angiogenesis, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Theresa Röhrig
- Division of Vascular Oncology and Metastasis, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Philipp Ströbel
- Institute of Pathology, University Medical Center Göttingen, University Göttingen, Göttingen, Germany
| | - Georg Stoecklin
- Helmholtz Junior Research Group, Posttranscriptional Control of Gene Expression, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany Center for Molecular Biology at the Heidelberg University, Heidelberg, Germany
| | - Ilse Hofmann
- Division of Vascular Oncology and Metastasis, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany Department of Vascular Biology and Tumor Angiogenesis, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
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12
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Belew AT, Meskauskas A, Musalgaonkar S, Advani VM, Sulima SO, Kasprzak WK, Shapiro BA, Dinman JD. Ribosomal frameshifting in the CCR5 mRNA is regulated by miRNAs and the NMD pathway. Nature 2014; 512:265-9. [PMID: 25043019 PMCID: PMC4369343 DOI: 10.1038/nature13429] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Accepted: 04/29/2014] [Indexed: 12/17/2022]
Abstract
Programmed -1 ribosomal frameshift (-1 PRF) signals redirect translating ribosomes to slip back one base on messenger RNAs. Although well characterized in viruses, how these elements may regulate cellular gene expression is not understood. Here we describe a -1 PRF signal in the human mRNA encoding CCR5, the HIV-1 co-receptor. CCR5 mRNA-mediated -1 PRF is directed by an mRNA pseudoknot, and is stimulated by at least two microRNAs. Mapping the mRNA-miRNA interaction suggests that formation of a triplex RNA structure stimulates -1 PRF. A -1 PRF event on the CCR5 mRNA directs translating ribosomes to a premature termination codon, destabilizing it through the nonsense-mediated mRNA decay pathway. At least one additional mRNA decay pathway is also involved. Functional -1 PRF signals that seem to be regulated by miRNAs are also demonstrated in mRNAs encoding six other cytokine receptors, suggesting a novel mode through which immune responses may be fine-tuned in mammalian cells.
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Affiliation(s)
- Ashton Trey Belew
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
| | - Arturas Meskauskas
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
- Department of Biotechnology and Microbiology, Vilnius University, Vilnius, LT 03101 Lithuania
| | - Sharmishtha Musalgaonkar
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
| | - Vivek M. Advani
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
| | - Sergey O. Sulima
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
- Present Address: Present address: VIB Center for the Biology of Disease, KU Leuven, Campus Gasthuisberg, Herestraat 49, bus 602, 3000 Leuven, Belgium.,
| | - Wojciech K. Kasprzak
- Basic Science Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, 21702 Maryland USA
| | - Bruce A. Shapiro
- Basic Research Laboratory, National Cancer Institute, Frederick, 21702 Maryland USA
| | - Jonathan D. Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, 20742 Maryland USA
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13
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Shum D, Bhinder B, Djaballah H. Modulators of the microRNA biogenesis pathway via arrayed lentiviral enabled RNAi screening for drug and biomarker discovery. Comb Chem High Throughput Screen 2014; 16:791-805. [PMID: 23977983 DOI: 10.2174/1386207311301010004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 07/23/2013] [Accepted: 07/24/2013] [Indexed: 01/05/2023]
Abstract
MicroRNAs (miRNAs) are small endogenous and conserved non-coding RNA molecules that regulate gene expression. Although the first miRNA was discovered well over sixteen years ago, little is known about their biogenesis and it is only recently that we have begun to understand their scope and diversity. For this purpose, we performed an RNAi screen aimed at identifying genes involved in their biogenesis pathway with a potential use as biomarkers. Using a previously developed miRNA 21 (miR-21) EGFP-based biosensor cell based assay monitoring green fluorescence enhancements, we performed an arrayed short hairpin RNA (shRNA) screen against a lentiviral particle ready TRC1 library covering 16,039 genes in 384-well plate format, and interrogating the genome one gene at a time building a panoramic view of endogenous miRNA activity. Using the BDA method for RNAi data analysis, we nominate 497 gene candidates the knockdown of which increased the EGFP fluorescence and yielding an initial hit rate of 3.09%; of which only 22, with reported validated clones, are deemed high-confidence gene candidates. An unexpected and surprising result was that only DROSHA was identified as a hit out of the seven core essential miRNA biogenesis genes; suggesting that perhaps intracellular shRNA processing into the correct duplex may be cell dependent and with differential outcome. Biological classification revealed several major control junctions among them genes involved in transport and vesicular trafficking. In summary, we report on 22 high confidence gene candidate regulators of miRNA biogenesis with potential use in drug and biomarker discovery.
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Affiliation(s)
- David Shum
- HTS Core Facility, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, New York 10065, USA.
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14
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Hoefig KP, Heissmeyer V. Degradation of oligouridylated histone mRNAs: see UUUUU and goodbye. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 5:577-89. [PMID: 24692427 DOI: 10.1002/wrna.1232] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 03/05/2014] [Accepted: 03/06/2014] [Indexed: 12/20/2022]
Abstract
During the cell cycle the expression of replication-dependent histones is tightly coupled to DNA synthesis. Histone messenger RNA (mRNA) levels strongly increase during early S-phase and rapidly decrease at the end of it. Here, we review the degradation of replication-dependent histone mRNAs, a paradigm of post-transcriptional gene regulation, in the context of processing, translation, and oligouridylation. Replication-dependent histone transcripts are characterized by the absence of introns and by the presence of a stem-loop structure at the 3' end of a very short 3' untranslated region (UTR). These features, together with a need for active translation, are a prerequisite for their rapid decay. The degradation is induced by 3' end additions of untemplated uridines, performed by terminal uridyl transferases. Such 3' oligouridylated transcripts are preferentially bound by the heteroheptameric LSM1-7 complex, which also interacts with the 3'→5' exonuclease ERI1 (also called 3'hExo). Presumably in cooperation with LSM1-7 and aided by the helicase UPF1, ERI1 degrades through the stem-loop of oligouridylated histone mRNAs in repeated rounds of partial degradation and reoligouridylation. Although histone mRNA decay is now known in some detail, important questions remain open: How is ceasing nuclear DNA replication relayed to the cytoplasmic histone mRNA degradation? Why is translation important for this process? Recent research on factors such as SLIP1, DBP5, eIF3, CTIF, CBP80/20, and ERI1 has provided new insights into the 3' end formation, the nuclear export, and the translation of histone mRNAs. We discuss how these results fit with the preparation of histone mRNAs for degradation, which starts as early as these transcripts are generated.
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Affiliation(s)
- Kai P Hoefig
- Institute of Molecular Immunology, Research Unit of Molecular Immune Regulation, Helmholtz Zentrum München, Munich, Germany
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15
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Abstract
Small-RNA-guided gene regulation has emerged as one of the fundamental principles in cell function, and the major protein players in this process are members of the Argonaute protein family. Argonaute proteins are highly specialized binding modules that accommodate the small RNA component - such as microRNAs (miRNAs), short interfering RNAs (siRNAs) or PIWI-associated RNAs (piRNAs) - and coordinate downstream gene-silencing events by interacting with other protein factors. Recent work has made progress in our understanding of classical Argonaute-mediated gene-silencing principles, such as the effects on mRNA translation and decay, but has also implicated Argonaute proteins in several other cellular processes, such as transcriptional regulation and splicing.
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16
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Frohn A, Eberl HC, Stöhr J, Glasmacher E, Rüdel S, Heissmeyer V, Mann M, Meister G. Dicer-dependent and -independent Argonaute2 protein interaction networks in mammalian cells. Mol Cell Proteomics 2012; 11:1442-56. [PMID: 22918229 DOI: 10.1074/mcp.m112.017756] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Argonaute (Ago) proteins interact with small regulatory RNAs such as microRNAs (miRNAs) and facilitate gene-silencing processes. miRNAs guide Ago proteins to specific mRNAs leading to translational silencing or mRNA decay. In order to understand the mechanistic details of miRNA function, it is important to characterize Ago protein interactors. Although several proteomic studies have been performed, it is not clear how the Ago interactome changes on miRNA or mRNA binding. Here, we report the analysis of Ago protein interactions in miRNA-containing and miRNA-depleted cells. Using stable isotope labeling in cell culture in conjunction with Dicer knock out mouse embryonic fibroblasts, we identify proteins that interact with Ago2 in the presence or the absence of Dicer. In contrast to our current view, we find that Ago-mRNA interactions can also take place in the absence of miRNAs. Our proteomics approach provides a rich resource for further functional studies on the cellular roles of Ago proteins.
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Affiliation(s)
- Anne Frohn
- Laboratory of RNA Biology, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
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17
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Wu X, Brewer G. The regulation of mRNA stability in mammalian cells: 2.0. Gene 2012; 500:10-21. [PMID: 22452843 DOI: 10.1016/j.gene.2012.03.021] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 02/20/2012] [Accepted: 03/04/2012] [Indexed: 12/24/2022]
Abstract
Messenger RNA decay is an essential step in gene expression to set mRNA abundance in the cytoplasm. The binding of proteins and/or noncoding RNAs to specific recognition sequences or secondary structures within mRNAs dictates mRNA decay rates by recruiting specific enzyme complexes that perform the destruction processes. Often, the cell coordinates the degradation or stabilization of functional subsets of mRNAs encoding proteins collectively required for a biological process. As well, extrinsic or intrinsic stimuli activate signal transduction pathways that modify the mRNA decay machinery with consequent effects on decay rates and mRNA abundance. This review is an update to our 2001 Gene review on mRNA stability in mammalian cells, and we survey the enormous progress made over the past decade.
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Affiliation(s)
- Xiangyue Wu
- Department of Molecular Genetics, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
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18
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Engels B, Jannot G, Remenyi J, Simard MJ, Hutvagner G. Polypyrimidine tract binding protein (hnRNP I) is possibly a conserved modulator of miRNA-mediated gene regulation. PLoS One 2012; 7:e33144. [PMID: 22427970 PMCID: PMC3302860 DOI: 10.1371/journal.pone.0033144] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2010] [Accepted: 02/10/2012] [Indexed: 11/19/2022] Open
Abstract
MiRNAs can regulate gene expression through versatile mechanisms that result in increased or decreased expression of the targeted mRNA and it could effect the expression of thousands of protein in a particular cell. An increasing body of evidence suggest that miRNAs action can be modulated by proteins that bind to the same 3′UTRs that are targeted by miRNAs, suggesting that other factors apart from miRNAs and their target sites determine miRNA-modulation of gene expression. We applied an affinity purification protocol using biotinylated let-7 miRNA inhibitor to isolate proteins that are involved in let-7 mediated gene regulation that resulted in an affinity purification of Polypyrimidine Tract Binding protein (PTB). Here we show that PTB interacts with miRNAs and human Argonaute 2 (hAgo2) through RNA as well as identified potential mammalian cellular targets that are co-regulated by PTB and hAgo2. In addition, using genetic approach, we have demonstrated that PTB genetically interacts with Caenorhabditis elegans let-7 indicating a conserved role for PTB in miRNA-mediated gene regulation.
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Affiliation(s)
- Bart Engels
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Guillaume Jannot
- Laval University Cancer Research Centre, Hôtel-Dieu de Québec (CHUQ), Québec City, Québec, Canada
| | - Judit Remenyi
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Martin J. Simard
- Laval University Cancer Research Centre, Hôtel-Dieu de Québec (CHUQ), Québec City, Québec, Canada
| | - György Hutvagner
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, United Kingdom
- Centre for Health Technologies, University of Technology, Sydney, Sydney, Australia
- * E-mail:
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19
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Hwang J, Maquat LE. Nonsense-mediated mRNA decay (NMD) in animal embryogenesis: to die or not to die, that is the question. Curr Opin Genet Dev 2012; 21:422-30. [PMID: 21550797 DOI: 10.1016/j.gde.2011.03.008] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 03/24/2011] [Accepted: 03/25/2011] [Indexed: 11/28/2022]
Abstract
Nonsense-mediated mRNA decay (NMD) is a well-studied cellular quality-control pathway. It decreases the half-lives of eukaryotic mRNAs that aberrantly contain premature termination codons and additionally regulates an estimated 10-20% of normal transcripts. NMD factors play crucial roles during embryogenesis in many animals. Here, we review data indicating that NMD factors are required for proper embryogenesis by discussing the abnormal developmental phenotypes that result when the abundance of individual NMD factors is either downregulated or completely eliminated. We conclude that while NMD per se affects the embryogenesis of all animals, it is required to avoid embryonic lethality in only some animals. The critical roles of many NMD factors in other metabolic pathways undoubtedly also contribute to embryonic development if not viability.
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Affiliation(s)
- Jungwook Hwang
- Department of Biochemistry and Biophysics and the Center for RNA Biology, School of Medicine and Dentistry, 601 Elmwood Avenue, Box 712, University of Rochester, Rochester, NY 14642, USA
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20
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Christie M, Brosnan CA, Rothnagel JA, Carroll BJ. RNA decay and RNA silencing in plants: competition or collaboration? FRONTIERS IN PLANT SCIENCE 2011; 2:99. [PMID: 22639621 PMCID: PMC3355627 DOI: 10.3389/fpls.2011.00099] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 11/30/2011] [Indexed: 05/25/2023]
Abstract
Initiation of RNA polymerase II transcription signals the beginning of a series of physically and functionally coupled pre-mRNA processing events that transform an RNA transcript into a highly structured, mature ribonucleoprotein complex. With such a complexity of co-transcriptional processes comes the need to identify and degrade improperly processed transcripts. Quality control of mRNA expression primarily involves exonucleolytic degradation of aberrant RNAs. RNA silencing, on the other hand, tends to be viewed separately as a pathway that primarily functions in regulating endogenous gene expression and in genome defense against transposons and viruses. Here, we review current knowledge of these pathways as they exist in plants and draw parallels to similar pathways in other eukaryotes. We then highlight some unexplored overlaps that exist between the RNA silencing and RNA decay pathways of plants, as evidenced by their shared RNA substrates and shared genetic requirements.
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Affiliation(s)
- Michael Christie
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbane, QLD, Australia
| | - Christopher A. Brosnan
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbane, QLD, Australia
| | - Joseph A. Rothnagel
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbane, QLD, Australia
| | - Bernard J. Carroll
- School of Chemistry and Molecular Biosciences, The University of QueenslandBrisbane, QLD, Australia
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21
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Zheng D, Chen CYA, Shyu AB. Unraveling regulation and new components of human P-bodies through a protein interaction framework and experimental validation. RNA (NEW YORK, N.Y.) 2011; 17:1619-34. [PMID: 21750099 PMCID: PMC3162328 DOI: 10.1261/rna.2789611] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The cellular factors involved in mRNA degradation and translation repression can aggregate into cytoplasmic domains known as GW bodies or mRNA processing bodies (P-bodies). However, current understanding of P-bodies, especially the regulatory aspect, remains relatively fragmentary. To provide a framework for studying the mechanisms and regulation of P-body formation, maintenance, and disassembly, we compiled a list of P-body proteins found in various species and further grouped both reported and predicted human P-body proteins according to their functions. By analyzing protein-protein interactions of human P-body components, we found that many P-body proteins form complex interaction networks with each other and with other cellular proteins that are not recognized as P-body components. The observation suggests that these other cellular proteins may play important roles in regulating P-body dynamics and functions. We further used siRNA-mediated gene knockdown and immunofluorescence microscopy to demonstrate the validity of our in silico analyses. Our combined approach identifies new P-body components and suggests that protein ubiquitination and protein phosphorylation involving 14-3-3 proteins may play critical roles for post-translational modifications of P-body components in regulating P-body dynamics. Our analyses provide not only a global view of human P-body components and their physical interactions but also a wealth of hypotheses to help guide future research on the regulation and function of human P-bodies.
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Affiliation(s)
- Dinghai Zheng
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School, Houston, Texas 77021, USA
| | - Chyi-Ying A. Chen
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School, Houston, Texas 77021, USA
| | - Ann-Bin Shyu
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School, Houston, Texas 77021, USA
- Corresponding author.E-mail .
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22
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Molecular mechanisms for the RNA-dependent ATPase activity of Upf1 and its regulation by Upf2. Mol Cell 2011; 41:693-703. [PMID: 21419344 DOI: 10.1016/j.molcel.2011.02.010] [Citation(s) in RCA: 205] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 11/29/2010] [Accepted: 01/07/2011] [Indexed: 01/08/2023]
Abstract
Upf1 is a crucial factor in nonsense-mediated mRNA decay, the eukaryotic surveillance pathway that degrades mRNAs containing premature stop codons. The essential RNA-dependent ATPase activity of Upf1 is triggered by the formation of the surveillance complex with Upf2-Upf3. We report crystal structures of Upf1 in the presence and absence of the CH domain, captured in the transition state with ADP:AlF₄⁻ and RNA. In isolation, Upf1 clamps onto the RNA, enclosing it in a channel formed by both the catalytic and regulatory domains. Upon binding to Upf2, the regulatory CH domain of Upf1 undergoes a large conformational change, causing the catalytic helicase domain to bind RNA less extensively and triggering its helicase activity. Formation of the surveillance complex thus modifies the RNA binding properties and the catalytic activity of Upf1, causing it to switch from an RNA-clamping mode to an RNA-unwinding mode.
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23
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A thymus-specific noncoding RNA, Thy-ncR1, is a cytoplasmic riboregulator of MFAP4 mRNA in immature T-cell lines. BMC Mol Biol 2010; 11:99. [PMID: 21162727 PMCID: PMC3023731 DOI: 10.1186/1471-2199-11-99] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Accepted: 12/16/2010] [Indexed: 12/13/2022] Open
Abstract
Background Postgenomic transcriptome analyses have identified large numbers of noncoding (nc)RNAs in mammalian cells. However, the biological function of long ncRNAs in mammalian cells remains largely unknown. Our recent expression profiling of selected human long ncRNAs revealed that a majority were expressed in an organ-specific manner, suggesting their function was linked to specific physiological phenomena in each organ. We investigated the characteristics and function of ncRNAs that were specifically expressed in the thymus, the site of T-cell selection and maturation. Results Expression profiling of 10 thymus-specific ncRNAs in 17 T-cell leukemia cell lines derived from various stages of T-cell maturation revealed that HIT14168 ncRNA, named Thy-ncR1, was specifically expressed in cell lines derived from stage III immature T cells in which the neighbouring CD1 gene cluster is also specifically activated. The Thy-ncR1 precursor exhibited complex alternative splicing patterns and differential usage of the 5' terminus leading to the production of an estimated 24 isoforms, which were predominantly located in the cytoplasm. Selective RNAi knockdown of each Thy-ncR1 isoform demonstrated that microfibril-associated glycoprotein 4 (MFAP4) mRNA was negatively regulated by two major Thy-ncR1 isoforms. Intriguingly, the MFAP4 mRNA level was controlled by a hUPF1-dependent mRNA degradation pathway in the cytoplasm distinct from nonsense-mediated decay. Conclusions This study identified Thy-ncR1 ncRNA to be specifically expressed in stage III immature T cells in which the neighbouring CD1 gene cluster was activated. Complex alternative splicing produces multiple Thy-ncR1 isoforms. Two major Thy-ncR1 isoforms are cytoplasmic riboregulators that suppress the expression of MFAP4 mRNA, which is degraded by an uncharacterized hUPF1-dependent pathway.
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24
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Vicente-Crespo M, Palacios IM. Nonsense-mediated mRNA decay and development: shoot the messenger to survive? Biochem Soc Trans 2010; 38:1500-5. [PMID: 21118115 PMCID: PMC3432441 DOI: 10.1042/bst0381500] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
NMD (nonsense-mediated mRNA decay) is a surveillance mechanism that degrades transcripts containing nonsense mutations, preventing the translation of potentially harmful truncated proteins. Although the mechanistic details of NMD are gradually being understood, the physiological role of this RNA surveillance pathway still remains largely unknown. The core NMD genes Upf1 (up-frameshift suppressor 1) and Upf2 are essential for animal viability in the fruitfly, mouse and zebrafish. These findings may reflect an important role for NMD during animal development. Alternatively, the lethal phenotypes of upf1 and upf2 mutants might be due to their function in NMD-independent processes. In the present paper, we describe the phenotypes observed when the NMD factors are mutated in various organisms, and discuss findings that might shed light on the function of NMD in cellular growth and development of an organism.
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Affiliation(s)
- Marta Vicente-Crespo
- Division of Biology, University of California San Diego, 9500 Gilman Drive, Bonner Hall 3230, La Jolla, CA 92093-0322, U.S.A
| | - Isabel M. Palacios
- Zoology Department, University of Cambridge, Downing Street, Cambridge CB2 3EJ, U.K
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