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Jamil M, Ahmad S, Ran Y, Ma S, Cao F, Lin X, Yan R. Argonaute1 and Gawky Are Required for the Development and Reproduction of Melon fly, Zeugodacus cucurbitae. Front Genet 2022; 13:880000. [PMID: 35812742 PMCID: PMC9260231 DOI: 10.3389/fgene.2022.880000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 05/04/2022] [Indexed: 11/18/2022] Open
Abstract
Argonaute family genes encode a highly conserved group of proteins that have been associated with RNA silencing in both animals and plants. This study investigates the importance of microRNA biogenesis key regulators Argonaute1 (Ago1) and Gawky genes in the post-embryonic and ovarian development of the melon fly, Zeugodacus cucurbitae. The expression levels of these genes were mapped in all developmental stages and different adult tissues. Their roles in development were investigated using RNA interference (RNAi) via two different dsRNA delivery techniques. Embryo microinjection and oral feeding of third instar larvae successfully knocked down and greatly reduced the expression level of the target genes. Additionally, ex vivo essays revealed the stability of dsRNA in food was sufficient for gene silencing, although its integrity was affected in midgut. A wide range of phenotypes were observed on pupation, segmentation, pigmentation, and ovarian development. RNAi-mediated silencing of Gawky caused high mortality and loss of body segmentation, while Ago1 knockdown affected ovarian development and pigmentation. Developmental abnormalities and ovarian malformations caused by silencing these genes suggest that these genes are crucial for viability and reproductive capacity of Z. cucurbitae, and may be used as potential target genes in pest management.
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Affiliation(s)
- Momana Jamil
- School of Life Sciences, Hainan University, Haikou, China
| | - Shakil Ahmad
- School of Plant Protection, Hainan University, Haikou, China
| | - Yingqiao Ran
- School of Plant Protection, Hainan University, Haikou, China
| | - Siya Ma
- School of Life Sciences, Hainan University, Haikou, China
| | - Fengqin Cao
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
- Hainan Yazhou Bay Seed Lab, Sanya, China
| | - Xianwu Lin
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
- *Correspondence: Xianwu Lin, ; Rihui Yan,
| | - Rihui Yan
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education, School of Plant Protection, Hainan University, Haikou, China
- Hainan Yazhou Bay Seed Lab, Sanya, China
- *Correspondence: Xianwu Lin, ; Rihui Yan,
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2
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Peters L, Depienne C, Klebe S. Familial adult myoclonic epilepsy (FAME): clinical features, molecular characteristics, pathophysiological aspects and diagnostic work-up. MED GENET-BERLIN 2021; 33:311-318. [PMID: 38835431 PMCID: PMC11006339 DOI: 10.1515/medgen-2021-2100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 11/16/2021] [Indexed: 06/06/2024]
Abstract
Familial adult myoclonic epilepsy (FAME) is a rare autosomal dominant disorder characterized by myoclonus and seizures. The genetic variant underlying FAME is an intronic repeat expansion composed of two different pentamers: an expanded TTTTA, which is the motif originally present at the locus, and an insertion of TTTCA repeats, which is usually located at the 3' end and likely corresponds to the pathogenic part of the expansion. This repeat expansion has been identified so far in six genes located on different chromosomes, which remarkably encode proteins with distinct cellular localizations and functions. Although the exact pathophysiological mechanisms remain to be clarified, it is likely that FAME repeat expansions lead to disease independently of the gene where they occur. We herein review the clinical and molecular characteristics of this singular genetic disorder, which interestingly shares clinical features with other more common neurological disorders whose etiology remains mainly unsolved.
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Affiliation(s)
- Lorenz Peters
- Department of Neurology, University Hospital Essen, Essen, Germany
| | - Christel Depienne
- Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Stephan Klebe
- Department of Neurology, University Hospital Essen, Essen, Germany
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3
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Cagliari D, Dias NP, Dos Santos EÁ, Rickes LN, Kremer FS, Farias JR, Lenz G, Galdeano DM, Garcia FRM, Smagghe G, Zotti MJ. First transcriptome of the Neotropical pest Euschistus heros (Hemiptera: Pentatomidae) with dissection of its siRNA machinery. Sci Rep 2020; 10:4856. [PMID: 32184426 PMCID: PMC7078254 DOI: 10.1038/s41598-020-60078-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 01/29/2020] [Indexed: 12/21/2022] Open
Abstract
Over the past few years, the use of RNA interference (RNAi) for insect pest management has attracted considerable interest in academia and industry as a pest-specific and environment-friendly strategy for pest control. For the success of this technique, the presence of core RNAi genes and a functional silencing machinery is essential. Therefore, the aim of this study was to test whether the Neotropical brown stinkbug Euschistus heros has the main RNAi core genes and whether the supply of dsRNA could generate an efficient gene silencing response. To do this, total mRNA of all developmental stages was sequenced on an Illumina platform, followed by a de novo assembly, gene annotation and RNAi-related gene identification. Once RNAi-related genes were identified, nuclease activities in hemolymph were investigated through an ex vivo assay. To test the functionality of the siRNA machinery, E. heros adults were microinjected with ~28 ng per mg of insect of a dsRNA targeting the V-ATPase-A gene. Mortality, relative transcript levels of V-ATPase-A, and the expression of the genes involved in the siRNA machinery, Dicer-2 (DCR-2) and Argonaute 2 (AGO-2), were analyzed. Transcriptome sequencing generated more than 126 million sequenced reads, and these were annotated in approximately 80,000 contigs. The search of RNAi-related genes resulted in 47 genes involved in the three major RNAi pathways, with the absence of sid-like homologous. Although ex vivo incubation of dsRNA in E. heros hemolymph showed rapid degradation, there was 35% mortality at 4 days after treatment and a significant reduction in V-ATPase-A gene expression. These results indicated that although sid-like genes are lacking, the dsRNA uptake mechanism was very efficient. Also, 2-fold and 4-fold overexpression of DCR-2 and AGO-2, respectively, after dsRNA supply indicated the activation of the siRNA machinery. Consequently, E. heros has proven to be sensitive to RNAi upon injection of dsRNA into its hemocoel. We believe that this finding together with a publically available transcriptome and the validation of a responsive RNAi machinery provide a starting point for future field applications against one of the most important soybean pests in South America.
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Affiliation(s)
- Deise Cagliari
- Department of Crop Protection, Molecular Entomology, Federal University of Pelotas, Pelotas, Brazil.
- Department of Plants and Crops, Ghent University, Ghent, Belgium.
| | - Naymã Pinto Dias
- Department of Crop Protection, Molecular Entomology, Federal University of Pelotas, Pelotas, Brazil
| | - Ericmar Ávila Dos Santos
- Department of Crop Protection, Molecular Entomology, Federal University of Pelotas, Pelotas, Brazil
| | - Leticia Neutzling Rickes
- Department of Crop Protection, Molecular Entomology, Federal University of Pelotas, Pelotas, Brazil
| | - Frederico Schmitt Kremer
- Center for Technological Development, Bioinformatics and Proteomics Laboratory, Federal University of Pelotas, Pelotas, Brazil
| | - Juliano Ricardo Farias
- Department of Crop Protection, Universidade Regional Integrada do Alto Uruguai, Santo Ângelo, Brazil
| | - Giuvan Lenz
- Agricultural Research and Development Center, UPL, Pereiras, Brazil
| | - Diogo Manzano Galdeano
- Sylvio Moreira Citrus Center, Agronomic Institute of Campinas, Cordeirópolis, São Paulo, Brazil
| | | | - Guy Smagghe
- Department of Plants and Crops, Ghent University, Ghent, Belgium.
| | - Moisés João Zotti
- Department of Crop Protection, Molecular Entomology, Federal University of Pelotas, Pelotas, Brazil.
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4
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Kina H, Yoshitani T, Hanyu-Nakamura K, Nakamura A. Rapid and efficient generation of GFP-knocked-in Drosophila by the CRISPR-Cas9-mediated genome editing. Dev Growth Differ 2019; 61:265-275. [PMID: 31037730 DOI: 10.1111/dgd.12607] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 03/20/2019] [Accepted: 03/21/2019] [Indexed: 11/30/2022]
Abstract
The CRISPR-Cas9 technology has been a powerful means to manipulate the genome in a wide range of organisms. A series of GFP knocked-in (GFPKI ) Drosophila strains have been generated through CRISPR-Cas9-induced double strand breaks coupled with homology-directed repairs in the presence of donor plasmids. They visualized specific cell types or intracellular structures in both fixed and live specimen. We provide a rapid and efficient strategy to identify KI lines. This method requires neither co-integration of a selection marker nor prior establishment of sgRNA-expressing transgenic lines. The injection of the mixture of a sgRNA/Cas9 expression plasmid and a donor plasmid into cleavage stage embryos efficiently generated multiple independent KI lines. A PCR-based selection allows to identify KI fly lines at the F1 generation (approximately 4 weeks after injection). These GFPKI strains have been deposited in the Kyoto Drosophila stock center, and made freely available to researchers at non-profit organizations. Thus, they will be useful resources for Drosophila research.
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Affiliation(s)
- Hirono Kina
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.,School of Pharmacy, Kumamoto University, Kumamoto, Japan
| | - Takashi Yoshitani
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.,School of Pharmacy, Kumamoto University, Kumamoto, Japan
| | - Kazuko Hanyu-Nakamura
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan
| | - Akira Nakamura
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto, Japan.,School of Pharmacy, Kumamoto University, Kumamoto, Japan.,Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto, Japan
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5
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Hanyu-Nakamura K, Matsuda K, Cohen SM, Nakamura A. Pgc suppresses the zygotically acting RNA decay pathway to protect germ plasm RNAs in the Drosophila embryo. Development 2019; 146:dev.167056. [PMID: 30890569 DOI: 10.1242/dev.167056] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 03/11/2019] [Indexed: 11/20/2022]
Abstract
Specification of germ cells is pivotal to ensure continuation of animal species. In many animal embryos, germ cell specification depends on maternally supplied determinants in the germ plasm. Drosophila polar granule component (pgc) mRNA is a component of the germ plasm. pgc encodes a small protein that is transiently expressed in newly formed pole cells, the germline progenitors, where it globally represses mRNA transcription. pgc is also required for pole cell survival, but the mechanism linking transcriptional repression to pole cell survival remains elusive. We report that pole cells lacking pgc show premature loss of germ plasm mRNAs, including the germ cell survival factor nanos, and undergo apoptosis. We found that pgc- pole cells misexpress multiple miRNA genes. Reduction of miRNA pathway activity in pgc- embryos partially suppressed germ plasm mRNA degradation and pole cell death, suggesting that Pgc represses zygotic miRNA transcription in pole cells to protect germ plasm mRNAs. Interestingly, germ plasm mRNAs are protected from miRNA-mediated degradation in vertebrates, albeit by a different mechanism. Thus, independently evolved mechanisms are used to silence miRNAs during germ cell specification.
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Affiliation(s)
- Kazuko Hanyu-Nakamura
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan.,Laboratory for Germline Development, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Kazuki Matsuda
- Laboratory for Germline Development, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan
| | - Stephen M Cohen
- Department of Cellular and Molecular Medicine, University of Copenhagen, 2200N Copenhagen, Denmark
| | - Akira Nakamura
- Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan .,Laboratory for Germline Development, RIKEN Center for Developmental Biology, Kobe, Hyogo 650-0047, Japan.,Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan
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6
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Role of GW182 protein in the cell. Int J Biochem Cell Biol 2018; 101:29-38. [PMID: 29791863 DOI: 10.1016/j.biocel.2018.05.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/23/2018] [Accepted: 05/17/2018] [Indexed: 12/27/2022]
Abstract
GW182 proteins interact directly with the argonaute proteins and constitute key components of miRNA repressor complexes (miRISC) in metazoans. As argonautes are insufficient for silencing they recruit the GW182 s that act as scaffold proteins inducing downstream translational repression, target mRNA deadenylation and exonucleolytic mRNA degradation. Besides their role as part of repressor complexes inside the cell, they function in wide variety of cellular processes as highlighted in this review. The present review summarises and discusses in detail our current knowledge of the GW182 s and their role inside the cell.
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7
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Swevers L, Liu J, Smagghe G. Defense Mechanisms against Viral Infection in Drosophila: RNAi and Non-RNAi. Viruses 2018; 10:E230. [PMID: 29723993 PMCID: PMC5977223 DOI: 10.3390/v10050230] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 04/20/2018] [Accepted: 04/27/2018] [Indexed: 12/20/2022] Open
Abstract
RNAi is considered a major antiviral defense mechanism in insects, but its relative importance as compared to other antiviral pathways has not been evaluated comprehensively. Here, it is attempted to give an overview of the antiviral defense mechanisms in Drosophila that involve both RNAi and non-RNAi. While RNAi is considered important in most viral infections, many other pathways can exist that confer antiviral resistance. It is noted that very few direct recognition mechanisms of virus infections have been identified in Drosophila and that the activation of immune pathways may be accomplished indirectly through cell damage incurred by viral replication. In several cases, protection against viral infection can be obtained in RNAi mutants by non-RNAi mechanisms, confirming the variability of the RNAi defense mechanism according to the type of infection and the physiological status of the host. This analysis is aimed at more systematically investigating the relative contribution of RNAi in the antiviral response and more specifically, to ask whether RNAi efficiency is affected when other defense mechanisms predominate. While Drosophila can function as a useful model, this issue may be more critical for economically important insects that are either controlled (agricultural pests and vectors of diseases) or protected from parasite infection (beneficial insects as bees) by RNAi products.
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Affiliation(s)
- Luc Swevers
- Institute of Biosciences & Applications, NCSR "Demokritos", 15341 Athens, Greece.
| | - Jisheng Liu
- School of Life Sciences, Guangzhou University, 510006 Guangzhou, China.
| | - Guy Smagghe
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium.
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8
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Gupta P, Li YR. Upf proteins: highly conserved factors involved in nonsense mRNA mediated decay. Mol Biol Rep 2017; 45:39-55. [PMID: 29282598 DOI: 10.1007/s11033-017-4139-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 12/14/2017] [Indexed: 11/28/2022]
Abstract
Over 10% of genetic diseases are caused by mutations that introduce a premature termination codon in protein-coding mRNA. Nonsense-mediated mRNA decay (NMD) is an essential cellular pathway that degrades these mRNAs to prevent the accumulation of harmful partial protein products. NMD machinery is also increasingly appreciated to play a role in other essential cellular functions, including telomere homeostasis and the regulation of normal mRNA turnover, and is misregulated in numerous cancers. Hence, understanding and designing therapeutics targeting NMD is an important goal in biomedical science. The central regulator of NMD, the Upf1 protein, interacts with translation termination factors and contextual factors to initiate NMD specifically on mRNAs containing PTCs. The molecular details of how these contextual factors affect Upf1 function remain poorly understood. Here, we review plausible models for the NMD pathway and the evidence for the variety of roles NMD machinery may play in different cellular processes.
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Affiliation(s)
- Puneet Gupta
- Harvard College, Harvard University, Cambridge, MA, 02138, USA.,School of Arts and Sciences, St. Bonaventure University, St. Bonaventure, NY, 14778, USA
| | - Yan-Ruide Li
- Harvard Medical School, Harvard University, Boston, MA, 02115, USA. .,College of Life Sciences, Zhejiang University, 866 Yu Hang Tang Road, Hangzhou, 310058, China.
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9
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Comprehensive Identification of Nuclear and Cytoplasmic TNRC6A-Associating Proteins. J Mol Biol 2017; 429:3319-3333. [DOI: 10.1016/j.jmb.2017.04.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 04/18/2017] [Accepted: 04/24/2017] [Indexed: 11/20/2022]
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10
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Bhadra U, Patra P, Chhatai J, Pal-Bhadra M. Pigmy MicroRNA: surveillance cops in Therapies kingdom. Mol Med 2016; 22:759-775. [PMID: 27704139 PMCID: PMC5193465 DOI: 10.2119/molmed.2016.00136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 09/13/2016] [Indexed: 11/06/2022] Open
Abstract
MicroRNAs (miRNAs) are well preserved in every animal. These pigmy sized non-coding RNAs (21-23 nt), scattered in genome, are responsible for micromanaging the versatile gene regulations. Involvement of miRNAs was surveillance cops in all human diseases including cardiovascular defects, tumor formation, reproductive pathways, and neurological and autoimmune disorders. The effective functional role of miRNA can be reduced by chemical entities of antisense oligonucleotides and versatile small molecules that support the views of novel therapy of different human diseases. In this study, we have updated our current understanding for designing and synthesizing miRNA-controlling therapeutic chemicals. We have also proposed various in-vivo delivery strategies and their ongoing challenges to combat the incorporation hurdles in live cells and animals. Lastly, we have demonstrated the current progress of miRNA modulation in the treatment of different human diseases that provides an alternative approach of gene therapy.
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Affiliation(s)
- Utpal Bhadra
- Functional Genomics and Gene Silencing Group, Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Pradipta Patra
- Functional Genomics and Gene Silencing Group, Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Jagamohan Chhatai
- Functional Genomics and Gene Silencing Group, Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India
| | - Manika Pal-Bhadra
- Centre for Chemical Biology, Indian Institute of Chemical Technology, Uppal Road, Hyderabad, India
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11
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Papanicolaou A, Schetelig MF, Arensburger P, Atkinson PW, Benoit JB, Bourtzis K, Castañera P, Cavanaugh JP, Chao H, Childers C, Curril I, Dinh H, Doddapaneni H, Dolan A, Dugan S, Friedrich M, Gasperi G, Geib S, Georgakilas G, Gibbs RA, Giers SD, Gomulski LM, González-Guzmán M, Guillem-Amat A, Han Y, Hatzigeorgiou AG, Hernández-Crespo P, Hughes DST, Jones JW, Karagkouni D, Koskinioti P, Lee SL, Malacrida AR, Manni M, Mathiopoulos K, Meccariello A, Munoz-Torres M, Murali SC, Murphy TD, Muzny DM, Oberhofer G, Ortego F, Paraskevopoulou MD, Poelchau M, Qu J, Reczko M, Robertson HM, Rosendale AJ, Rosselot AE, Saccone G, Salvemini M, Savini G, Schreiner P, Scolari F, Siciliano P, Sim SB, Tsiamis G, Ureña E, Vlachos IS, Werren JH, Wimmer EA, Worley KC, Zacharopoulou A, Richards S, Handler AM. The whole genome sequence of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), reveals insights into the biology and adaptive evolution of a highly invasive pest species. Genome Biol 2016; 17:192. [PMID: 27659211 PMCID: PMC5034548 DOI: 10.1186/s13059-016-1049-2] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 08/26/2016] [Indexed: 01/01/2023] Open
Abstract
Background The Mediterranean fruit fly (medfly), Ceratitis capitata, is a major destructive insect pest due to its broad host range, which includes hundreds of fruits and vegetables. It exhibits a unique ability to invade and adapt to ecological niches throughout tropical and subtropical regions of the world, though medfly infestations have been prevented and controlled by the sterile insect technique (SIT) as part of integrated pest management programs (IPMs). The genetic analysis and manipulation of medfly has been subject to intensive study in an effort to improve SIT efficacy and other aspects of IPM control. Results The 479 Mb medfly genome is sequenced from adult flies from lines inbred for 20 generations. A high-quality assembly is achieved having a contig N50 of 45.7 kb and scaffold N50 of 4.06 Mb. In-depth curation of more than 1800 messenger RNAs shows specific gene expansions that can be related to invasiveness and host adaptation, including gene families for chemoreception, toxin and insecticide metabolism, cuticle proteins, opsins, and aquaporins. We identify genes relevant to IPM control, including those required to improve SIT. Conclusions The medfly genome sequence provides critical insights into the biology of one of the most serious and widespread agricultural pests. This knowledge should significantly advance the means of controlling the size and invasive potential of medfly populations. Its close relationship to Drosophila, and other insect species important to agriculture and human health, will further comparative functional and structural studies of insect genomes that should broaden our understanding of gene family evolution. Electronic supplementary material The online version of this article (doi:10.1186/s13059-016-1049-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alexie Papanicolaou
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Marc F Schetelig
- Justus-Liebig-University Giessen, Institute for Insect Biotechnology, 35394, Giessen, Germany
| | - Peter Arensburger
- Department of Biological Sciences, Cal Poly Pomona, Pomona, CA, 91768, USA
| | - Peter W Atkinson
- Department of Entomology and Center for Disease Vector Research, University of California Riverside, Riverside, CA, 92521, USA.,Interdepartmental Graduate Program in Genetics, Genomics & Bioinformatics, University of California Riverside, Riverside, CA, 92521, USA
| | - Joshua B Benoit
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Kostas Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Seibersdorf, Vienna, Austria.,Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Greece
| | - Pedro Castañera
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - John P Cavanaugh
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Hsu Chao
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | | | - Ingrid Curril
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Huyen Dinh
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - HarshaVardhan Doddapaneni
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Amanda Dolan
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Shannon Dugan
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Markus Friedrich
- Department of Biological Sciences, Wayne State University, Detroit, MI, 48202, USA
| | - Giuliano Gasperi
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Scott Geib
- USDA-ARS, Pacific Basin Agricultural Research Center, Hilo, HI, 96720, USA
| | - Georgios Georgakilas
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Richard A Gibbs
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Sarah D Giers
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Ludvik M Gomulski
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Miguel González-Guzmán
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Ana Guillem-Amat
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Yi Han
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Artemis G Hatzigeorgiou
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Pedro Hernández-Crespo
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Daniel S T Hughes
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Jeffery W Jones
- Department of Biological Sciences, Oakland University, Rochester, MI, 48309, USA
| | - Dimitra Karagkouni
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Panagiota Koskinioti
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Sandra L Lee
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Anna R Malacrida
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Mosè Manni
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Kostas Mathiopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Angela Meccariello
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | | | - Shwetha C Murali
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Terence D Murphy
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Donna M Muzny
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Georg Oberhofer
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Félix Ortego
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Maria D Paraskevopoulou
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - Monica Poelchau
- National Agricultural Library, USDA, Beltsville, MD, 20705, USA
| | - Jiaxin Qu
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Martin Reczko
- Institute of Molecular Biology and Genetics, Biomedical Sciences Research Centre "Alexander Fleming", Vari, Greece
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Andrew J Rosendale
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Andrew E Rosselot
- Department of Biological Sciences, University of Cincinnati, Cincinnati, OH, 45221, USA
| | - Giuseppe Saccone
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | - Marco Salvemini
- Department of Biology, University of Naples Federico II, 80126, Naples, Italy
| | - Grazia Savini
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Patrick Schreiner
- Interdepartmental Graduate Program in Genetics, Genomics & Bioinformatics, University of California Riverside, Riverside, CA, 92521, USA
| | - Francesca Scolari
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Paolo Siciliano
- Department of Biology and Biotechnology, University of Pavia, 27100, Pavia, Italy
| | - Sheina B Sim
- USDA-ARS, Pacific Basin Agricultural Research Center, Hilo, HI, 96720, USA
| | - George Tsiamis
- Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Greece
| | - Enric Ureña
- Department of Environmental Biology, Centro de Investigaciones Biológicas, CSIC, 28040, Madrid, Spain
| | - Ioannis S Vlachos
- DIANA-Lab, Department of Electrical & Computer Engineering, University of Thessaly, 382 21 Volos, Greece and Hellenic Pasteur Institute, 11521, Athens, Greece
| | - John H Werren
- Department of Biology, University of Rochester, Rochester, NY, 14627, USA
| | - Ernst A Wimmer
- Georg-August-Universität Göttingen, Johann-Friedrich-Blumenbach-Institut für Zoologie und Anthropologie, 37077, Göttingen, Germany
| | - Kim C Worley
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | | | - Stephen Richards
- Human Genome Sequencing Center, Department of Human and Molecular Genetics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Alfred M Handler
- USDA-ARS, Center for Medical, Agricultural, and Veterinary Entomology, 1700 S.W. 23rd Drive, Gainesville, FL, 32608, USA.
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12
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Baron MN, Klinger CM, Rachubinski RA, Simmonds AJ. A Systematic Cell-Based Analysis of Localization of PredictedDrosophilaPeroxisomal Proteins. Traffic 2016; 17:536-53. [DOI: 10.1111/tra.12384] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/29/2016] [Accepted: 01/29/2016] [Indexed: 12/22/2022]
Affiliation(s)
- Matthew N. Baron
- Department of Cell Biology; University of Alberta; Medical Sciences Building 5-14 Edmonton AB T6G 2H7 Canada
| | - Christen M. Klinger
- Department of Cell Biology; University of Alberta; Medical Sciences Building 5-14 Edmonton AB T6G 2H7 Canada
| | - Richard A. Rachubinski
- Department of Cell Biology; University of Alberta; Medical Sciences Building 5-14 Edmonton AB T6G 2H7 Canada
| | - Andrew J. Simmonds
- Department of Cell Biology; University of Alberta; Medical Sciences Building 5-14 Edmonton AB T6G 2H7 Canada
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13
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Patel PH, Barbee SA, Blankenship JT. GW-Bodies and P-Bodies Constitute Two Separate Pools of Sequestered Non-Translating RNAs. PLoS One 2016; 11:e0150291. [PMID: 26930655 PMCID: PMC4773245 DOI: 10.1371/journal.pone.0150291] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 02/11/2016] [Indexed: 01/05/2023] Open
Abstract
Non-translating RNAs that have undergone active translational repression are culled from the cytoplasm into P-bodies for decapping-dependent decay or for sequestration. Organisms that use microRNA-mediated RNA silencing have an additional pathway to remove RNAs from active translation. Consequently, proteins that govern microRNA-mediated silencing, such as GW182/Gw and AGO1, are often associated with the P-bodies of higher eukaryotic organisms. Due to the presence of Gw, these structures have been referred to as GW-bodies. However, several reports have indicated that GW-bodies have different dynamics to P-bodies. Here, we use live imaging to examine GW-body and P-body dynamics in the early Drosophila melanogaster embryo. While P-bodies are present throughout early embryonic development, cytoplasmic GW-bodies only form in significant numbers at the midblastula transition. Unlike P-bodies, which are predominantly cytoplasmic, GW-bodies are present in both nuclei and the cytoplasm. RNA decapping factors such as DCP1, Me31B, and Hpat are not associated with GW-bodies, indicating that P-bodies and GW-bodies are distinct structures. Furthermore, known Gw interactors such as AGO1 and the CCR4-NOT deadenylation complex, which have been shown to be important for Gw function, are also not present in GW-bodies. Use of translational inhibitors puromycin and cycloheximide, which respectively increase or decrease cellular pools of non-translating RNAs, alter GW-body size, underscoring that GW-bodies are composed of non-translating RNAs. Taken together, these data indicate that active translational silencing most likely does not occur in GW-bodies. Instead GW-bodies most likely function as repositories for translationally silenced RNAs. Finally, inhibition of zygotic gene transcription is unable to block the formation of either P-bodies or GW-bodies in the early embryo, suggesting that these structures are composed of maternal RNAs.
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Affiliation(s)
- Prajal H. Patel
- Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, United States of America
| | - Scott A. Barbee
- Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, United States of America
- Molecular and Cellular Biophysics Program, University of Denver, Denver, Colorado, United States of America
- * E-mail: (JTB); (SAB)
| | - J. Todd Blankenship
- Department of Biological Sciences and Eleanor Roosevelt Institute, University of Denver, Denver, Colorado, United States of America
- Molecular and Cellular Biophysics Program, University of Denver, Denver, Colorado, United States of America
- * E-mail: (JTB); (SAB)
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14
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Prentice K, Pertry I, Christiaens O, Bauters L, Bailey A, Niblett C, Ghislain M, Gheysen G, Smagghe G. Transcriptome analysis and systemic RNAi response in the African sweetpotato weevil (Cylas puncticollis, Coleoptera, Brentidae). PLoS One 2015; 10:e0115336. [PMID: 25590333 PMCID: PMC4295849 DOI: 10.1371/journal.pone.0115336] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/21/2014] [Indexed: 01/04/2023] Open
Abstract
The African sweetpotato weevil (SPW) Cylas puncticollis Boheman is one of the most important constraints of sweetpotato production in Sub-Saharan Africa and yet is largely an uncharacterized insect pest. Here, we report on the transcriptome analysis of SPW generated using an Illumina platform. More than 213 million sequencing reads were obtained and assembled into 89,599 contigs. This assembly was followed by a gene ontology annotation. Subsequently, a transcriptome search showed that the necessary RNAi components relevant to the three major RNAi pathways, were found to be expressed in SPW. To address the functionality of the RNAi mechanism in this species, dsRNA was injected into second instar larvae targeting laccase2, a gene which encodes an enzyme involved in the sclerotization of insect exoskeleton. The body of treated insects showed inhibition of sclerotization, leading eventually to death. Quantitative Real Time PCR (qPCR) confirmed this phenotype to be the result of gene silencing. Together, our results provide valuable sequence data on this important insect pest and demonstrate that a functional RNAi pathway with a strong and systemic effect is present in SPW and can further be explored as a new strategy for controlling this important pest.
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Affiliation(s)
- Katterinne Prentice
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
- Department of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
- International Potato Center (CIP), Genomics and Biotechnology Program, Nairobi 00603, Kenya
| | - Ine Pertry
- VIB, Institute of Plant Biotechnology Outreach, Technologiepark 3, B-9052 Ghent, Belgium
- Ghent University, Department Molecular Biotechnology, Institute of Plant Biotechnology Outreach, Technologiepark 3, B-9052 Ghent, Belgium
| | - Olivier Christiaens
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
| | - Lander Bauters
- Department of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
| | - Ana Bailey
- Venganza Inc., St. Augustine, FL 32080, United States of America
| | - Chuck Niblett
- Venganza Inc., St. Augustine, FL 32080, United States of America
| | - Marc Ghislain
- International Potato Center (CIP), Genomics and Biotechnology Program, Nairobi 00603, Kenya
| | - Godelieve Gheysen
- Department of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
| | - Guy Smagghe
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, B-9000 Ghent, Belgium
- * E-mail:
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15
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Fukaya T, Iwakawa HO, Tomari Y. MicroRNAs block assembly of eIF4F translation initiation complex in Drosophila. Mol Cell 2014; 56:67-78. [PMID: 25280104 DOI: 10.1016/j.molcel.2014.09.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 07/09/2014] [Accepted: 08/28/2014] [Indexed: 12/20/2022]
Abstract
miRNAs silence their complementary target mRNAs by translational repression as well as by poly(A) shortening and mRNA decay. In Drosophila, miRNAs are typically incorporated into Argonaute1 (Ago1) to form the effector complex called RNA-induced silencing complex (RISC). Ago1-RISC associates with a scaffold protein GW182, which recruits additional silencing factors. We have previously shown that miRNAs repress translation initiation by blocking formation of the 48S and 80S ribosomal complexes. However, it remains unclear how ribosome recruitment is impeded. Here, we examined the assembly of translation initiation factors on the target mRNA under repression. We show that Ago1-RISC induces dissociation of eIF4A, a DEAD-box RNA helicase, from the target mRNA without affecting 5' cap recognition by eIF4E in a manner independent of GW182. In contrast, direct tethering of GW182 promotes dissociation of both eIF4E and eIF4A. We propose that miRNAs act to block the assembly of the eIF4F complex during translation initiation.
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Affiliation(s)
- Takashi Fukaya
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Medical Genome Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Hiro-Oki Iwakawa
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Yukihide Tomari
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Medical Genome Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan.
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16
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Temme C, Simonelig M, Wahle E. Deadenylation of mRNA by the CCR4-NOT complex in Drosophila: molecular and developmental aspects. Front Genet 2014; 5:143. [PMID: 24904643 PMCID: PMC4033318 DOI: 10.3389/fgene.2014.00143] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Accepted: 05/02/2014] [Indexed: 11/13/2022] Open
Abstract
Controlled shortening of the poly(A) tail of mRNAs is the first step in eukaryotic mRNA decay and can also be used for translational inactivation of mRNAs. The CCR4-NOT complex is the most important among a small number of deadenylases, enzymes catalyzing poly(A) tail shortening. Rates of poly(A) shortening differ between mRNAs as the CCR4-NOT complex is recruited to specific mRNAs by means of either sequence-specific RNA binding proteins or miRNAs. This review summarizes our current knowledge concerning the subunit composition and deadenylation activity of the Drosophila CCR4-NOT complex and the mechanisms by which the complex is recruited to particular mRNAs. We discuss genetic data implicating the complex in the regulation of specific mRNAs, in particular in the context of development.
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Affiliation(s)
- Claudia Temme
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg Halle, Germany
| | - Martine Simonelig
- Genetics and Development, Institute of Human Genetics - CNRS UPR1142 Montpellier, France
| | - Elmar Wahle
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg Halle, Germany
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17
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Swevers L, Kolliopoulou A, Li Z, Daskalaki M, Verret F, Kalantidis K, Smagghe G, Sun J. Transfection of BmCPV genomic dsRNA in silkmoth-derived Bm5 cells: stability and interactions with the core RNAi machinery. JOURNAL OF INSECT PHYSIOLOGY 2014; 64:21-9. [PMID: 24636911 DOI: 10.1016/j.jinsphys.2014.03.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 03/03/2014] [Accepted: 03/07/2014] [Indexed: 06/03/2023]
Abstract
While several studies have been conducted to investigate the stability of dsRNA in the extracellular medium (hemolymph, gut content, saliva), little is known regarding the persistence of dsRNA once it has been introduced into the cell. Here, we investigate the stability of Bombyx mori cytoplasmic polyhedrosis virus (BmCPV) genomic dsRNA fragments after transfection into Bombyx-derived Bm5 cells. Using RT-PCR as a detection method, we found that dsRNA could persist for long periods (up to 8 days) in the intracellular environment. While the BmCPV genomic dsRNA was processed by the RNAi machinery, its presence had no effects on other RNAi processes, such as the silencing of a luciferase reporter by dsLuc. We also found that transfection of BmCPV genomic dsRNA could not establish a viral infection in the Bm5 cells, even when co-transfections were carried out with dsRNAs targeting Dicer and Argonaute genes, suggesting that the neutralization by RNAi does not play a role in the establishment of an in vitro culture system. The mechanism of the dsRNA stability in Bm5 cells is discussed, as well as the implications for the establishment for an in vitro culture system for BmCPV.
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Affiliation(s)
- Luc Swevers
- Insect Molecular Genetics and Biotechnology, Institute of Biosciences and Applications, National Centre for Scientific Research "Demokritos", P. Grigoriou & Neapoleos Str, Aghia Paraskevi Attikis, 153 42 Athens, Greece.
| | - Anna Kolliopoulou
- Insect Molecular Genetics and Biotechnology, Institute of Biosciences and Applications, National Centre for Scientific Research "Demokritos", P. Grigoriou & Neapoleos Str, Aghia Paraskevi Attikis, 153 42 Athens, Greece
| | - Zheng Li
- Guangdong Engineering Research Center of Subtropical Sericulture and Mulberry Resources Protection and Safety, Guangdong Provincial Key Lab of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Maria Daskalaki
- Department of Biology, University of Crete, Voutes University Campus, 700 13 Heraklion, Crete, Greece
| | - Frederic Verret
- Department of Biology, University of Crete, Voutes University Campus, 700 13 Heraklion, Crete, Greece
| | - Kriton Kalantidis
- Department of Biology, University of Crete, Voutes University Campus, 700 13 Heraklion, Crete, Greece
| | - Guy Smagghe
- Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Jingchen Sun
- Guangdong Engineering Research Center of Subtropical Sericulture and Mulberry Resources Protection and Safety, Guangdong Provincial Key Lab of Agro-animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, People's Republic of China.
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18
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Swevers L, Huvenne H, Menschaert G, Kontogiannatos D, Kourti A, Pauchet Y, ffrench-Constant R, Smagghe G. Colorado potato beetle (Coleoptera) gut transcriptome analysis: expression of RNA interference-related genes. INSECT MOLECULAR BIOLOGY 2013; 22:668-684. [PMID: 24580832 DOI: 10.1111/imb.12054] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the search for new methods of pest control, the potential of RNA interference (RNAi) is being explored. Because the gut is the first barrier for the uptake of double-stranded (ds)RNA, pyrosequencing of the gut transcriptome is a powerful tool for obtaining the necessary sequences for specific dsRNA-mediated pest control. In the present study, a dataset representing the gut transcriptome of the Colorado potato beetle (CPB; Leptinotarsa decemlineata) was generated and analysed for the presence of RNAi-related genes. Almost all selected genes that were implicated in silencing efficiency at different levels in the RNAi pathway (core machinery, associated intracellular factors, dsRNA uptake, antiviral RNAi, nucleases), which uses different types of small RNA (small interfering RNA, microRNA and piwi-RNA), were expressed in the CPB gut. Although the database is of lower quality, the majority of the RNAi genes are also found to be present in the gut transcriptome of the tobacco hornworm [TH; Manduca sexta (19 out of 35 genes analysed)]. The high quality of the CPB transcriptome database will lay the foundation for future gene expression and functional studies regarding the gut and RNAi.
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Affiliation(s)
- L Swevers
- Insect Molecular Genetics and Biotechnology, NCSR 'Demokritos', Institute of Biosciences & Applications, Athens, Greece
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19
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Swevers L, Vanden Broeck J, Smagghe G. The possible impact of persistent virus infection on the function of the RNAi machinery in insects: a hypothesis. Front Physiol 2013; 4:319. [PMID: 24204347 PMCID: PMC3817476 DOI: 10.3389/fphys.2013.00319] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Accepted: 10/15/2013] [Indexed: 11/13/2022] Open
Abstract
RNAi experiments in insects are characterized by great variability in efficiency; for instance beetles and locusts are very amenable to dsRNA-mediated gene silencing, while other insect groups, most notably lepidopterans, are more refractory to RNAi. Several factors can be forwarded that could affect the efficiency of RNAi, such as the composition and function of the intracellular RNAi machinery, the mechanism of dsRNA uptake, the presence of dsRNA- and siRNA-degrading enzymes and non-specific activation of the innate immune response. In this essay, we investigate the evidence whether persistent infection with RNA viruses could be a major factor that affects the response to exogenous dsRNA in insects. The occurrence of RNA viruses in different insect groups will be discussed, as well as several mechanisms by which viruses could interfere with the process of RNAi. Finally, the impact of RNA virus infection on the design of dsRNA-based insect control strategies will be considered.
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Affiliation(s)
- Luc Swevers
- Insect Molecular Genetics and Biotechnology, Institute of Biosciences and Applications, National Center for Scientific Research "Demokritos," Athens, Greece
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20
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Insco ML, Bailey AS, Kim J, Olivares GH, Wapinski OL, Tam CH, Fuller MT. A self-limiting switch based on translational control regulates the transition from proliferation to differentiation in an adult stem cell lineage. Cell Stem Cell 2013; 11:689-700. [PMID: 23122292 DOI: 10.1016/j.stem.2012.08.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 07/13/2012] [Accepted: 08/28/2012] [Indexed: 12/11/2022]
Abstract
In adult stem cell lineages, progenitor cells commonly undergo mitotic transit amplifying (TA) divisions before terminal differentiation, allowing production of many differentiated progeny per stem cell division. Mechanisms that limit TA divisions and trigger the switch to differentiation may protect against cancer by preventing accumulation of oncogenic mutations in the proliferating population. Here we show that the switch from TA proliferation to differentiation in the Drosophila male germline stem cell lineage is mediated by translational control. The TRIM-NHL tumor suppressor homolog Mei-P26 facilitates accumulation of the differentiation regulator Bam in TA cells. In turn, Bam and its partner Bgcn bind the mei-P26 3' untranslated region and repress translation of mei-P26 in late TA cells. Thus, germ cells progress through distinct, sequential regulatory states, from Mei-P26 on/Bam off to Bam on/Mei-P26 off. TRIM-NHL homologs across species facilitate the switch from proliferation to differentiation, suggesting a conserved developmentally programmed tumor suppressor mechanism.
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Affiliation(s)
- Megan L Insco
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA
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21
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Li J, Hobman TC, Simmonds AJ. Gawky (GW) is the Drosophila melanogaster GW182 homologue. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 768:127-45. [PMID: 23224968 DOI: 10.1007/978-1-4614-5107-5_8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jing Li
- Department of Cell Biology, University of Alberta, Edmonton, Canada.
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22
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Moser JJ, Fritzler MJ. Relationship of other cytoplasmic ribonucleoprotein bodies (cRNPB) to GW/P bodies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 768:213-42. [PMID: 23224973 DOI: 10.1007/978-1-4614-5107-5_13] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
GW/P body components are involved in the post-transcriptional -processing of messenger RNA (mRNA) through the RNA interference and 5' → 3' mRNA degradation pathways, as well as functioning in mRNA transport and stabilization. It is currently thought that the relevant mRNA silencing and degrading factors are partitioned to these cytoplasmic microdomains thus effecting post-transcriptional regulation and the prevention of accidental degradation of functional mRNA. Although much attention has focused on GW/P bodies, a variety of other cytoplasmic RNP bodies (cRNPB) also have highly specialized functions and have been shown to interact or co-localize with components of GW/P bodies. These cRNPB include neuronal transport RNP granules, stress granules, RNP-rich cytoplasmic germline granules or chromatoid bodies, sponge bodies, cytoplasmic prion protein-induced RNP granules, U bodies and TAM bodies. Of clinical relevance, autoantibodies directed against protein and miRNA components of GW/P bodies have been associated with autoimmune diseases, neurological diseases and cancer. Understanding the molecular function of GW/P bodies and their interactions with other cRNPB may provide clues to the etiology or pathogenesis of diseases associated with autoantibodies directed to these structures. This chapter will focus on the similarities and differences of the various cRNPB as an approach to understanding their functional relationships to GW/P bodies.
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Affiliation(s)
- Joanna J Moser
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
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23
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Yao B, Li S, Chan EKL. Function of GW182 and GW bodies in siRNA and miRNA pathways. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2013; 768:71-96. [PMID: 23224966 DOI: 10.1007/978-1-4614-5107-5_6] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
GW182 is an 182 kDa protein with multiple glycine/tryptophan repeats (GW or WG) playing a central role in siRNA- and miRNA-mediated gene silencing. GW182 interacts with its functional partner Argonaute proteins (AGO) via multiple domains to exert its silencing activity in both pathways. In siRNA-mediated silencing, knockdown either GW182 or Ago2 causes loss of silencing activity correlating with the disassembly of GWBs. In contrast, GW182 and its longer isoform TNGW1 appear to be downstream repressors that function independent of Ago2, whereas the Ago2-GW182 interaction is critical for the localization of Ago2 in the cytoplasmic foci and its repression function. GW182 contains two non-overlapping repression domains that can trigger translational repression with mild effect on mRNA decay. Collectively, GW182 plays a critical role in miRNA-mediated gene silencing.
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Affiliation(s)
- Bing Yao
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA
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24
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Jiang Z, Yu N, Kuang P, Chen M, Shao F, Martin G, Chui DHK, Cardoso WV, Ai X, Lü J. Trinucleotide repeat containing 6a (Tnrc6a)-mediated microRNA function is required for development of yolk sac endoderm. J Biol Chem 2011; 287:5979-87. [PMID: 22187428 DOI: 10.1074/jbc.m111.297937] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Tnrc6 family members (Tnrc6a/b/c) are key components of the RNA-induced silencing complex in microRNA (miRNA)-mediated gene suppression. Here, we show that Tnrc6a, also known as GW182, is selectively expressed in the yolk sac endoderm and that gene trap disruption of GW182 leads to growth arrest and apoptosis. We found that targets of miRNAs highly expressed in the yolk sac are significantly derepressed in GW182(gt/gt) mutant mice, although levels of miRNAs are not altered. Specifically, growth arrest and apoptosis phenotype are associated with significant derepression of Cdkn1a (p21), Cdkn1c (P27), Lats1, Lats2, Rb1, Rbl, Bim, and Pten, known targets of miRNAs from miR-17/20/93/106 clusters highly expressed in yolk sac endoderm. Together, these data strongly suggest that GW182 is an essential functional component in the RNA-induced silencing complex for miRNA-mediated gene silencing in vivo, and selectively regulation of miRNA activity plays an important role in the proper development of yolk sac.
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Affiliation(s)
- Zhihua Jiang
- Pulmonary Center, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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25
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Hafner M, Ascano M, Tuschl T. New insights in the mechanism of microRNA-mediated target repression. Nat Struct Mol Biol 2011; 18:1181-2. [PMID: 22056803 DOI: 10.1038/nsmb.2170] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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26
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Li J, Najand N, Long W, Simmonds A. Imaging the cellular dynamics of Drosophila Argonaute proteins. Methods Mol Biol 2011; 725:143-59. [PMID: 21528452 DOI: 10.1007/978-1-61779-046-1_10] [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] [Indexed: 02/03/2023]
Abstract
Drosophila melanogaster is used extensively as a model system to uncover genetic and molecular pathways that regulate various cellular activities. There are five members of the Argonaute protein family in Drosophila. Argonautes have been found to be localized to cytoplasmic ribonucleoprotein containing structures in both cultured Drosophila cells and developing embryos. However, in fixed cell preparations some Drosophila Argonaute family proteins co-localize with structures containing known as RNA processing (P) body components while others do not. The ability to image Argonaute family proteins in live Drosophila cells, (both cultured and within developing embryos) allows for accurate genetic dissection of the pathways involved in the assembly, mobility, disassembly, and other dynamic processes of Argonaute-containing bodies. Here we describe a method of rapidly creating vectors for, and assay the activity of, fluorescently tagged Argonaute proteins in cultured Drosophila cells and embryos.
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Affiliation(s)
- Jing Li
- Faculty of Medicine and Dentistry, Department of Cell Biology, University of Alberta, Edmonton, AB, Canada
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Terenius O, Papanicolaou A, Garbutt JS, Eleftherianos I, Huvenne H, Kanginakudru S, Albrechtsen M, An C, Aymeric JL, Barthel A, Bebas P, Bitra K, Bravo A, Chevalier F, Collinge DP, Crava CM, de Maagd RA, Duvic B, Erlandson M, Faye I, Felföldi G, Fujiwara H, Futahashi R, Gandhe AS, Gatehouse HS, Gatehouse LN, Giebultowicz JM, Gómez I, Grimmelikhuijzen CJP, Groot AT, Hauser F, Heckel DG, Hegedus DD, Hrycaj S, Huang L, Hull JJ, Iatrou K, Iga M, Kanost MR, Kotwica J, Li C, Li J, Liu J, Lundmark M, Matsumoto S, Meyering-Vos M, Millichap PJ, Monteiro A, Mrinal N, Niimi T, Nowara D, Ohnishi A, Oostra V, Ozaki K, Papakonstantinou M, Popadic A, Rajam MV, Saenko S, Simpson RM, Soberón M, Strand MR, Tomita S, Toprak U, Wang P, Wee CW, Whyard S, Zhang W, Nagaraju J, Ffrench-Constant RH, Herrero S, Gordon K, Swevers L, Smagghe G. RNA interference in Lepidoptera: an overview of successful and unsuccessful studies and implications for experimental design. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:231-45. [PMID: 21078327 DOI: 10.1016/j.jinsphys.2010.11.006] [Citation(s) in RCA: 540] [Impact Index Per Article: 41.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 11/03/2010] [Accepted: 11/04/2010] [Indexed: 05/03/2023]
Abstract
Gene silencing through RNA interference (RNAi) has revolutionized the study of gene function, particularly in non-model insects. However, in Lepidoptera (moths and butterflies) RNAi has many times proven to be difficult to achieve. Most of the negative results have been anecdotal and the positive experiments have not been collected in such a way that they are possible to analyze. In this review, we have collected detailed data from more than 150 experiments including all to date published and many unpublished experiments. Despite a large variation in the data, trends that are found are that RNAi is particularly successful in the family Saturniidae and in genes involved in immunity. On the contrary, gene expression in epidermal tissues seems to be most difficult to silence. In addition, gene silencing by feeding dsRNA requires high concentrations for success. Possible causes for the variability of success in RNAi experiments in Lepidoptera are discussed. The review also points to a need to further investigate the mechanism of RNAi in lepidopteran insects and its possible connection to the innate immune response. Our general understanding of RNAi in Lepidoptera will be further aided in the future as our public database at http://insectacentral.org/RNAi will continue to gather information on RNAi experiments.
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Affiliation(s)
- Olle Terenius
- Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
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28
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Khong A, Jan E. Modulation of stress granules and P bodies during dicistrovirus infection. J Virol 2011; 85:1439-51. [PMID: 21106737 PMCID: PMC3028890 DOI: 10.1128/jvi.02220-10] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 11/16/2010] [Indexed: 11/20/2022] Open
Abstract
Stress granules (SGs) are dynamic cytosolic aggregates composed of ribonucleoproteins that are induced during cellular stress when protein synthesis is inhibited. The function of SGs is poorly understood, but they are thought to be sites for reorganizing mRNA and protein. Several viruses can modulate SG formation, suggesting that SGs have an impact on virus infection. In this study, we have investigated the relationship of SG formation in Drosophila S2 cells infected by cricket paralysis virus (CrPV), a member of the Dicistroviridae family. Despite a rapid shutoff of host translation during CrPV infection, several hallmark SG markers such as the Drosophila TIA-1 and G3BP (RasGAP-SH3-binding protein) homologs, Rox8 and Rin, respectively, do not aggregate in CrPV-infected cells, even when challenged with potent SG inducers such as heat shock, oxidative stress, and pateamine A treatment. Furthermore, we demonstrate that a subset of P body markers become moderately dispersed at late times of infection. In contrast, as shown by fluorescent in situ hybridization, poly(A)(+) RNA granules still form at late times of infection. These poly(A)(+) RNA granules do not contain viral RNA nor do they colocalize with P body markers. Finally, our results demonstrate that the CrPV viral 3C protease is sequestered to SGs under cellular stress but not during virus infection. In summary, we propose that dicistrovirus infection leads to the selective inhibition of distinct SGs so that viral proteins are available for viral processing.
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Affiliation(s)
- Anthony Khong
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver BC V6T 1Z3, Canada
| | - Eric Jan
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver BC V6T 1Z3, Canada
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29
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Kim MS, Oh JE, Kim YR, Park SW, Kang MR, Kim SS, Ahn CH, Yoo NJ, Lee SH. Somatic mutations and losses of expression of microRNA regulation-related genes AGO2 and TNRC6A in gastric and colorectal cancers. J Pathol 2010; 221:139-46. [PMID: 20198652 DOI: 10.1002/path.2683] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Mounting evidence indicates that deregulation of microRNAs (miRNAs) are involved in development of many human diseases, including cancers. Regulation of miRNA is a complicated process and some components in the regulation are known to be altered in human cancers. Among the miRNA regulation-related genes, we found that AGO1, AGO2, TNRC6A, TNRC6C, TARBP2 and EXPORTIN5 genes have mononucleotide repeats in their coding sequences. To see whether these genes are mutated in cancers with microsatellite instability (MSI), we analysed the mononucleotide repeats in 27 gastric cancers (GCs) with high MSI (MSI-H), 18 GC with low MSI (MSI-L), 45 GC with stable MSI (MSS), 41 colorectal cancers (CRCs) with MSI-H, 14 CRCs with MSI-L and 45 CRCs with stable MSI (MSS) by single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. We found AGO2, TNRC6A, TARBP2, TNRC6C and EXPORTIN5 mutations in 10, six, one, one and one cancer(s), respectively. They were detected in MSI-H but not in MSI-L or MSS cancers. The GCs and CRCs with MSI-H harboured one or more mutations of the genes in 22% and 27%, respectively. We also analysed Ago2 and TNRC6A protein expressions in GCs and CRCs with MSI-H. In cancers with MSI-H, loss of Ago2 expression was observed in 40% of GCs and 35% of CRCs, while loss of TNRC6A was observed in 52% of the GCs and 54% of the CRCs. Our data indicate that frameshift mutations in AGO2 and TNRC6A and their losses of expression are common in GCs and CRCs with MSI-H, and suggest that these alterations may contribute to the cancer development by deregulating miRNA regulation.
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Affiliation(s)
- Min S Kim
- Department of Pathology, College of Medicine, Catholic University of Korea, Seoul, Korea
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30
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Temme C, Zhang L, Kremmer E, Ihling C, Chartier A, Sinz A, Simonelig M, Wahle E. Subunits of the Drosophila CCR4-NOT complex and their roles in mRNA deadenylation. RNA (NEW YORK, N.Y.) 2010; 16:1356-1370. [PMID: 20504953 PMCID: PMC2885685 DOI: 10.1261/rna.2145110] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Accepted: 04/16/2010] [Indexed: 05/27/2023]
Abstract
The CCR4-NOT complex is the main enzyme catalyzing the deadenylation of mRNA. We have investigated the composition of this complex in Drosophila melanogaster by immunoprecipitation with a monoclonal antibody directed against NOT1. The CCR4, CAF1 (=POP2), NOT1, NOT2, NOT3, and CAF40 subunits were associated in a stable complex, but NOT4 was not. Factors known to be involved in mRNA regulation were prominent among the other proteins coprecipitated with the CCR4-NOT complex, as analyzed by mass spectrometry. The complex was localized mostly in the cytoplasm but did not appear to be a major component of P bodies. Of the known CCR4 paralogs, Nocturnin was found associated with the subunits of the CCR4-NOT complex, whereas Angel and 3635 were not. RNAi experiments in Schneider cells showed that CAF1, NOT1, NOT2, and NOT3 are required for bulk poly(A) shortening and hsp70 mRNA deadenylation, but knock-down of CCR4, CAF40, and NOT4 did not affect these processes. Overexpression of catalytically dead CAF1 had a dominant-negative effect on mRNA decay. In contrast, overexpression of inactive CCR4 had no effect. We conclude that CAF1 is the major catalytically important subunit of the CCR4-NOT complex in Drosophila Schneider cells. Nocturnin may also be involved in mRNA deadenylation, whereas there is no evidence for a similar role of Angel and 3635.
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Affiliation(s)
- Claudia Temme
- Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06099 Halle, Germany
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31
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Karlowski WM, Zielezinski A, Carrère J, Pontier D, Lagrange T, Cooke R. Genome-wide computational identification of WG/GW Argonaute-binding proteins in Arabidopsis. Nucleic Acids Res 2010; 38:4231-45. [PMID: 20338883 PMCID: PMC2910046 DOI: 10.1093/nar/gkq162] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Domains in Arabidopsis proteins NRPE1 and SPT5-like, composed almost exclusively of repeated motifs in which only WG or GW sequences and an overall amino-acid preference are conserved, have been experimentally shown to bind multiple molecules of Argonaute (AGO) protein(s). Domain swapping between the WG/GW domains of NRPE1 and the human protein GW182 showed a conserved function. As classical sequence alignment methods are poorly-adapted to detect such weakly-conserved motifs, we have developed a tool to carry out a systematic analysis to identify genes potentially encoding AGO-binding GW/WG proteins. Here, we describe exhaustive analysis of the Arabidopsis genome for all regions potentially encoding proteins bearing WG/GW motifs and consider the possible role of some of them in AGO-dependent mechanisms. We identified 20 different candidate WG/GW genes, encoding proteins in which the predicted domains range from 92aa to 654aa. These mostly correspond to a limited number of families: RNA-binding proteins, transcription factors, glycine-rich proteins, translation initiation factors and known silencing-associated proteins such as SDE3. Recent studies have argued that the interaction between WG/GW-rich domains and AGO proteins is evolutionarily conserved. Here, we demonstrate by an in silico domain-swapping simulation between plant and mammalian WG/GW proteins that the biased amino-acid composition of the AGO-binding sites is conserved.
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Affiliation(s)
- Wojciech M Karlowski
- Bioinformatics Laboratory, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, 61-614 Poznan, Poland.
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Abstract
P-bodies (processing bodies) are cytoplasmic foci visible by light microscopy in somatic cells of vertebrate and invertebrate origin as well as in yeast, plants and trypanosomes. At the molecular level, P-bodies are dynamic aggregates of specific mRNAs and proteins that serve a dual function: first, they harbour mRNAs that are translationally silenced, and such mRNA can exit again from P-bodies to re-engage in translation. Secondly, P-bodies recruit mRNAs that are targeted for deadenylation and degradation by the decapping/Xrn1 pathway. Whereas certain proteins are core constituents of P-bodies, others involved in recognizing short-lived mRNAs can only be trapped in P-bodies when mRNA decay is attenuated. This reflects the very transient interactions by which many proteins associate with P-bodies. In the present review, we summarize recent findings on the function, assembly and motility of P-bodies. An updated list of proteins and RNAs that localize to P-bodies will help in keeping track of this fast-growing field.
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Shen XH, Han YJ, Cui XS, Kim NH. Ago2 and GW182 expression in mouse preimplantation embryos: a link between microRNA biogenesis and GW182 protein synthesis. Reprod Fertil Dev 2010; 22:634-43. [DOI: 10.1071/rd09188] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2009] [Accepted: 09/28/2009] [Indexed: 12/11/2022] Open
Abstract
MicroRNA-mediated RNA interference appears to play a role in early development and differentiation processes in preimplantation embryos. However, the expression of its key effectors, including Ago2, a key component of the RNA-induced silencing complex, and GW182, a critical component of GW bodies (GWBs), has not been assessed in preimplantation embryos. To characterise the roles of Ago2 and GW182 in early embryo development, we determined their transcription and protein synthesis in mouse embryos. Transcript levels of Ago2 and GW182 increased steadily from the one-cell stage through to the blastocyst stage when data were not normalised against an internal reference. However, when normalised against the internal standard, transcript levels for both genes were highest in four-cell stage embryos and decreased steadily through to the blastocyst stage. Indirect immunocytochemistry showed that both AGO2 and GW182 proteins were expressed in each stage in the early embryo and were observed to colocalise in the morula and blastocyst stages. Specific silencing of mRNA expression by short interference (si) RNA against Ago2 or Dicer1 decreased the expression of selected apoptosis- and development-related microRNAs, but did not inhibit development up to the blastocyst stage. However, transcription levels of Oct3/4, Nanog and Sox2 were decreased in both Ago2- and Dicer1-knockdown embryos at the blastocyst stage. Furthermore, although knockdown of these genes did not change transcript levels of GW182, GW182 protein synthesis was decreased in blastocyst stage embryos. These results suggest that Ago2 and Dicer1 regulate GW182 protein expression in mouse embryos, which is linked to microRNA biogenesis and likely to be important for differentiation in the blastocyst stage.
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Pepper ASR, Beerman RW, Bhogal B, Jongens TA. Argonaute2 suppresses Drosophila fragile X expression preventing neurogenesis and oogenesis defects. PLoS One 2009; 4:e7618. [PMID: 19888420 PMCID: PMC2770736 DOI: 10.1371/journal.pone.0007618] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 10/01/2009] [Indexed: 01/05/2023] Open
Abstract
Fragile X Syndrome is caused by the silencing of the Fragile X Mental Retardation gene (FMR1). Regulating dosage of FMR1 levels is critical for proper development and function of the nervous system and germ line, but the pathways responsible for maintaining normal expression levels are less clearly defined. Loss of Drosophila Fragile X protein (dFMR1) causes several behavioral and developmental defects in the fly, many of which are analogous to those seen in Fragile X patients. Over-expression of dFMR1 also causes specific neuronal and behavioral abnormalities. We have found that Argonaute2 (Ago2), the core component of the small interfering RNA (siRNA) pathway, regulates dfmr1 expression. Previously, the relationship between dFMR1 and Ago2 was defined by their physical interaction and co-regulation of downstream targets. We have found that Ago2 and dFMR1 are also connected through a regulatory relationship. Ago2 mediated repression of dFMR1 prevents axon growth and branching defects of the Drosophila neuromuscular junction (NMJ). Consequently, the neurogenesis defects in larvae mutant for both dfmr1 and Ago2 mirror those in dfmr1 null mutants. The Ago2 null phenotype at the NMJ is rescued in animals carrying an Ago2 genomic rescue construct. However, animals carrying a mutant Ago2 allele that produces Ago2 with significantly reduced endoribonuclease catalytic activity are normal with respect to the NMJ phenotypes examined. dFMR1 regulation by Ago2 is also observed in the germ line causing a multiple oocyte in a single egg chamber mutant phenotype. We have identified Ago2 as a regulator of dfmr1 expression and have clarified an important developmental role for Ago2 in the nervous system and germ line that requires dfmr1 function.
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Affiliation(s)
- Anita S.-R. Pepper
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Rebecca W. Beerman
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Balpreet Bhogal
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Thomas A. Jongens
- Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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35
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Zhang L, Hammell M, Kudlow BA, Ambros V, Han M. Systematic analysis of dynamic miRNA-target interactions during C. elegans development. Development 2009; 136:3043-55. [PMID: 19675127 PMCID: PMC2730362 DOI: 10.1242/dev.039008] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2009] [Indexed: 11/20/2022]
Abstract
Although microRNA (miRNA)-mediated functions have been implicated in many aspects of animal development, the majority of miRNA::mRNA regulatory interactions remain to be characterized experimentally. We used an AIN/GW182 protein immunoprecipitation approach to systematically analyze miRNA::mRNA interactions during C. elegans development. We characterized the composition of miRNAs in functional miRNA-induced silencing complexes (miRISCs) at each developmental stage and identified three sets of miRNAs with distinct stage-specificity of function. We then identified thousands of miRNA targets in each developmental stage, including a significant portion that is subject to differential miRNA regulation during development. By identifying thousands of miRNA family-mRNA pairs with temporally correlated patterns of AIN-2 association, we gained valuable information on the principles of physiological miRNA::target recognition and predicted 1589 high-confidence miRNA family::mRNA interactions. Our data support the idea that miRNAs preferentially target genes involved in signaling processes and avoid genes with housekeeping functions, and that miRNAs orchestrate temporal developmental programs by coordinately targeting or avoiding genes involved in particular biological functions.
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Affiliation(s)
- Liang Zhang
- Howard Hughes Medical Institute and Department of MCDB, University of Colorado, Boulder, CO 80309, USA
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36
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Eulalio A, Tritschler F, Izaurralde E. The GW182 protein family in animal cells: new insights into domains required for miRNA-mediated gene silencing. RNA (NEW YORK, N.Y.) 2009; 15:1433-42. [PMID: 19535464 PMCID: PMC2714752 DOI: 10.1261/rna.1703809] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
GW182 family proteins interact directly with Argonaute proteins and are required for miRNA-mediated gene silencing in animal cells. The domains of the GW182 proteins have recently been studied to determine their role in silencing. These studies revealed that the middle and C-terminal regions function as an autonomous domain with a repressive function that is independent of both the interaction with Argonaute proteins and of P-body localization. Such findings reinforce the idea that GW182 proteins are key components of miRNA repressor complexes in metazoa.
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Affiliation(s)
- Ana Eulalio
- Department of Biochemistry, Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
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37
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Miyoshi K, Okada TN, Siomi H, Siomi MC. Characterization of the miRNA-RISC loading complex and miRNA-RISC formed in the Drosophila miRNA pathway. RNA (NEW YORK, N.Y.) 2009; 15:1282-91. [PMID: 19451544 PMCID: PMC2704077 DOI: 10.1261/rna.1541209] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2009] [Accepted: 04/14/2009] [Indexed: 05/22/2023]
Abstract
In Drosophila, miRNA is processed by Dicer-1 (DCR-1) from its precursor and loaded onto Argonaute1 (AGO1). AGO1 recognizes target mRNAs based on the miRNA sequence and suppresses the expression at post-transcriptional levels. GW182, a P-body component, localizes the AGO1 complex to processing bodies (P-bodies) where mRNA targets are decayed or stored. However, the details of the pathway remain elusive. In this study, two distinct types of AGO1-containing complexes from Drosophila Schneider2 (S2) cells were isolated and compared at the molecular level. The AGO1 complex with DCR-1 contained neither mature miRNA nor GW182 but exhibited pre-miRNA processing activity. The resultant mature RNA was loaded onto AGO1 within the complex. The AGO1 complex with GW182 excluded DCR-1, but possessed mature miRNA and showed no pre-miRNA processing activity. Thus, the AGO1-DCR-1 and AGO1-GW182 complexes correspond to miRLC (miRISC loading complex) and miRISC, respectively. The requirement for various domains of AGO1 in miRNA-loading and DCR-1/GW182 interaction was also examined. The Mid domain mutant (F2V2) interacted with DCR-1 but not with mature miRNA and GW182. The AGO1-PAZ mutant lacks the mature miRNA-binding ability but associates with either DCR-1 or GW182. The AGO1-PIWI mutant showed no Slicer activity but associates with mature miRNA. These results indicate that these domains are required differently for miRLC and miRISC formation in the miRNA pathway.
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Affiliation(s)
- Keita Miyoshi
- School of Medicine, Keio University, Tokyo 160-8582, Japan
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38
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Abstract
Sponge bodies, cytoplasmic structures containing post-transcriptional regulatory factors, are distributed throughout the nurse cells and oocytes of the Drosophila ovary and share components with P bodies of yeast and mammalian cells. We show that sponge body composition differs between nurse cells and the oocyte, and that the sponge bodies change composition rapidly after entry into the oocyte. We identify conditions that affect sponge body organization. At one extreme, components are distributed relatively uniformly or in small dispersed bodies. At the other extreme, components are present in large reticulated bodies. Both types of sponge bodies allow normal development, but show substantial differences in distribution of Staufen protein and oskar mRNA, whose localization within the oocyte is essential for axial patterning. Based on these and other results we propose a model for the relationship between P bodies and the various cytoplasmic bodies containing P body proteins in the Drosophila ovary.
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Affiliation(s)
- Mark J Snee
- Institute for Cellular and Molecular Biology, Section of Molecular, Cell, and Developmental Biology, The University of Texas at Austin, Austin, Texas, USA
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39
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Eulalio A, Helms S, Fritzsch C, Fauser M, Izaurralde E. A C-terminal silencing domain in GW182 is essential for miRNA function. RNA (NEW YORK, N.Y.) 2009; 15:1067-77. [PMID: 19383769 PMCID: PMC2685512 DOI: 10.1261/rna.1605509] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Proteins of the GW182 family are essential for miRNA-mediated gene silencing in animal cells; they interact with Argonaute proteins (AGOs) and are required for both the translational repression and mRNA degradation mediated by miRNAs. To gain insight into the role of the GW182-AGO1 interaction in silencing, we generated protein mutants that do not interact and tested them in complementation assays. We show that silencing of miRNA targets requires the N-terminal domain of GW182, which interacts with AGO1 through multiple glycine-tryptophan (GW)-repeats. Indeed, a GW182 mutant that does not interact with AGO1 cannot rescue silencing in cells depleted of endogenous GW182. Conversely, silencing is impaired by mutations in AGO1 that strongly reduce the interaction with GW182 but not with miRNAs. We further show that a GW182 mutant that does not localize to P-bodies but interacts with AGO1 rescues silencing in GW182-depleted cells, even though in these cells, AGO1 also fails to localize to P-bodies. Finally, we show that in addition to the N-terminal AGO1-binding domain, the middle and C-terminal regions of GW182 (referred to as the bipartite silencing domain) are essential for silencing. Together our results indicate that miRNA silencing in animal cells is mediated by AGO1 in complex with GW182, and that P-body localization is not required for silencing.
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Affiliation(s)
- Ana Eulalio
- Max Planck Institute for Developmental Biology, D-72076 Tübingen, Germany
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40
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Lian SL, Li S, Abadal GX, Pauley BA, Fritzler MJ, Chan EKL. The C-terminal half of human Ago2 binds to multiple GW-rich regions of GW182 and requires GW182 to mediate silencing. RNA (NEW YORK, N.Y.) 2009; 15:804-13. [PMID: 19324964 PMCID: PMC2673069 DOI: 10.1261/rna.1229409] [Citation(s) in RCA: 110] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
MicroRNA (miRNA)-mediated silencing is a post-transcriptional mechanism that regulates translation of mRNAs primarily via their 3'-UTR. Ago2 binds miRNA directly and is the core component of miRNA-induced silencing complex. GW182 is another important factor in miRNA-mediated silencing, and its interaction with Ago2 is evolutionarily conserved. However, the GW182-Ago2 interaction in humans has not been characterized thoroughly, and the role of GW182 in the mammalian miRNA pathway remains unclear. In the current study, we generated a set of GST-, green fluorescence protein (GFP)-, or 3xFlag-tagged deletion constructs of GW182 and Ago2 to further analyze GW182-Ago2 interactions. The C-terminal half of Ago2 interacted with four nonoverlapping GW-rich regions of GW182, and this interaction recruited Ago2 to GWB. Furthermore, the interaction with GW182 was observed in all four human Ago proteins. Most interestingly, tethering the C-terminal half of Ago2 to the 3'-UTR of reporter mRNA recapitulated translational repression comparable to that of tethered Ago2, and this repression was greatly impaired upon GW182 knockdown. In comparison, the N-terminal half of Ago2 did not bind GW182 and did not retain the repression function of Ago2. Our data strongly support a model in which Ago2 recruits GW182 to the 3'-UTR of mRNA to mediate silencing, and suggest that GW182 may contribute to enhancement in translational repression by interacting with multiple Ago proteins from multiple miRNA target sites in the same or adjacent 3'UTR.
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Affiliation(s)
- Shang L Lian
- Department of Oral Biology, University of Florida, Gainesville, Florida 32610-0424, USA
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41
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Zipprich JT, Bhattacharyya S, Mathys H, Filipowicz W. Importance of the C-terminal domain of the human GW182 protein TNRC6C for translational repression. RNA (NEW YORK, N.Y.) 2009; 15:781-93. [PMID: 19304925 PMCID: PMC2673060 DOI: 10.1261/rna.1448009] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Proteins of the GW182 family play an important role in the execution of microRNA repression in metazoa. They interact directly with Argonaute proteins, components of microRNPs, and also form part of P-bodies, structures implicated in translational repression and mRNA degradation. Recent results demonstrated that Drosophila GW182 has the potential to both repress translation and accelerate mRNA deadenylation and decay. In contrast to a single GW182 protein in Drosophila, the three GW182 paralogs TNRC6A, TNRC6B, and TNRC6C are encoded in mammalian genomes. In this study, we provide evidence that TNRC6C, like TNRC6A and TNRC6B, is important for efficient miRNA repression. We further demonstrate that tethering of each of the human TNRC6 proteins to a reporter mRNA has a dramatic inhibitory effect on protein synthesis. The repression is due to a combination of effects on the mRNA level and mRNA translation. Through deletion and mutagenesis, we identified the C-terminal part of TNRC6C encompassing the RRM RNA-binding motif as a key effector domain mediating protein synthesis repression by TNRC6C.
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Affiliation(s)
- Jakob T Zipprich
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
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Eulalio A, Tritschler F, Büttner R, Weichenrieder O, Izaurralde E, Truffault V. The RRM domain in GW182 proteins contributes to miRNA-mediated gene silencing. Nucleic Acids Res 2009; 37:2974-83. [PMID: 19295135 PMCID: PMC2685099 DOI: 10.1093/nar/gkp173] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Proteins of the GW182 family interact with Argonaute proteins and are required for miRNA-mediated gene silencing. These proteins contain two structural domains, an ubiquitin-associated (UBA) domain and an RNA recognition motif (RRM), embedded in regions predicted to be unstructured. The structure of the RRM of Drosophila melanogaster GW182 reveals that this domain adopts an RRM fold, with an additional C-terminal α-helix. The helix lies on the β-sheet surface, generally used by these domains to bind RNA. This, together with the absence of aromatic residues in the conserved RNP1 and RNP2 motifs, and the lack of general affinity for RNA, suggests that the GW182 RRM does not bind RNA. The domain may rather engage in protein interactions through an unusual hydrophobic cleft exposed on the opposite face of the β-sheet. We further show that the GW182 RRM is dispensable for P-body localization and for interaction of GW182 with Argonaute-1 and miRNAs. Nevertheless, its deletion impairs the silencing activity of GW182 in a miRNA target-specific manner, indicating that this domain contributes to silencing. The conservation of structural and surface residues suggests that the RRM domain adopts a similar fold with a related function in insect and vertebrate GW182 family members.
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Affiliation(s)
- Ana Eulalio
- Max Planck Institute for Developmental Biology, Tübingen, Germany
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43
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Franks TM, Lykke-Andersen J. The control of mRNA decapping and P-body formation. Mol Cell 2009; 32:605-15. [PMID: 19061636 DOI: 10.1016/j.molcel.2008.11.001] [Citation(s) in RCA: 321] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Indexed: 01/24/2023]
Abstract
mRNA decapping is a critical step in eukaryotic cytoplasmic mRNA turnover. Cytoplasmic mRNA decapping is catalyzed by Dcp2 in conjunction with its coactivator Dcp1 and is stimulated by decapping enhancer proteins. mRNAs associated with the decapping machinery can assemble into cytoplasmic mRNP granules called processing bodies (PBs). Evidence suggests that PB-associated mRNPs are translationally repressed and can be degraded or stored for subsequent translation. However, whether mRNP assembly into a PB is important for translational repression, decapping, or decay has remained controversial. Here, we discuss the regulation of decapping machinery recruitment to specific mRNPs and how their assembly into PBs is governed by the relative rates of translational repression, mRNP multimerization, and mRNA decay.
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Affiliation(s)
- Tobias M Franks
- Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309, USA
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Abstract
NMD (nonsense-mediated mRNA decay) is a mechanism that degrades transcripts containing PTCs (premature translation termination codons). NMD is a translation-associated process that is expected to take place throughout the cytoplasm. However, recent studies have indicated that the core NMD factors UPF1 (up-frameshift-1), UPF2 and UPF3 can associate with P-bodies (processing bodies), which are large cytoplasmic granules replete with proteins involved in general mRNA decay and related processes. It has been proposed that UPF1 directs PTC-containing mRNAs to P-bodies and triggers decay. Here, we discuss the link between P-bodies and NMD in view of recent studies that suggest that P-bodies are not required for NMD in Drosophila.
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45
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Liu J. Control of protein synthesis and mRNA degradation by microRNAs. Curr Opin Cell Biol 2008; 20:214-21. [PMID: 18329869 DOI: 10.1016/j.ceb.2008.01.006] [Citation(s) in RCA: 198] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2007] [Accepted: 01/26/2008] [Indexed: 11/29/2022]
Affiliation(s)
- Jidong Liu
- Cell Biology Program, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
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46
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Mechanisms of post-transcriptional regulation by microRNAs: are the answers in sight? Nat Rev Genet 2008; 9:102-14. [PMID: 18197166 DOI: 10.1038/nrg2290] [Citation(s) in RCA: 3861] [Impact Index Per Article: 241.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
MicroRNAs constitute a large family of small, approximately 21-nucleotide-long, non-coding RNAs that have emerged as key post-transcriptional regulators of gene expression in metazoans and plants. In mammals, microRNAs are predicted to control the activity of approximately 30% of all protein-coding genes, and have been shown to participate in the regulation of almost every cellular process investigated so far. By base pairing to mRNAs, microRNAs mediate translational repression or mRNA degradation. This Review summarizes the current understanding of the mechanistic aspects of microRNA-induced repression of translation and discusses some of the controversies regarding different modes of microRNA function.
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Mechanistic relationships between Drosophila fragile X mental retardation protein and metabotropic glutamate receptor A signaling. Mol Cell Neurosci 2008; 37:747-60. [PMID: 18280750 DOI: 10.1016/j.mcn.2008.01.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Revised: 12/20/2007] [Accepted: 01/03/2008] [Indexed: 11/23/2022] Open
Abstract
Fragile X syndrome is caused by loss of the FMRP translational regulator. A current hypothesis proposes that FMRP functions downstream of mGluR signaling to regulate synaptic connections. Using the Drosophila disease model, we test relationships between dFMRP and the sole Drosophila mGluR (DmGluRA) by assaying protein expression, behavior and neuron structure in brain and NMJ; in single mutants, double mutants and with an mGluR antagonist. At the protein level, dFMRP is upregulated in dmGluRA mutants, and DmGluRA is upregulated in dfmr1 mutants, demonstrating mutual negative feedback. Null dmGluRA mutants display defects in coordinated movement behavior, which are rescued by removing dFMRP expression. Null dfmr1 mutants display increased NMJ presynaptic structural complexity and elevated presynaptic vesicle pools, which are rescued by blocking mGluR signaling. Null dfmr1 brain neurons similarly display increased presynaptic architectural complexity, which is rescued by blocking mGluR signaling. These data show that DmGluRA and dFMRP convergently regulate presynaptic properties.
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48
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El-Shami M, Pontier D, Lahmy S, Braun L, Picart C, Vega D, Hakimi MA, Jacobsen SE, Cooke R, Lagrange T. Reiterated WG/GW motifs form functionally and evolutionarily conserved ARGONAUTE-binding platforms in RNAi-related components. Genes Dev 2007; 21:2539-44. [PMID: 17938239 PMCID: PMC2000319 DOI: 10.1101/gad.451207] [Citation(s) in RCA: 232] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2007] [Accepted: 08/30/2007] [Indexed: 11/24/2022]
Abstract
Two forms of RNA Polymerase IV (PolIVa/PolIVb) have been implicated in RNA-directed DNA methylation (RdDM) in Arabidopsis. Prevailing models imply a distinct function for PolIVb by association of Argonaute4 (AGO4) with the C-terminal domain (CTD) of its largest subunit NRPD1b. Here we show that the extended CTD of NRPD1b-type proteins exhibits conserved Argonaute-binding capacity through a WG/GW-rich region that functionally distinguishes Pol IVb from Pol IVa, and that is essential for RdDM. Site-specific mutagenesis and domain-swapping experiments between AtNRPD1b and the human protein GW182 demonstrated that reiterated WG/GW motifs form evolutionarily and functionally conserved Argonaute-binding platforms in RNA interference (RNAi)-related components.
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Affiliation(s)
- Mahmoud El-Shami
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Dominique Pontier
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Sylvie Lahmy
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Laurence Braun
- Institut Jean Roget, Université Joseph Fourier, BP170, 38042 Grenoble Cedex 9, France
| | - Claire Picart
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Danielle Vega
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Mohamed-Ali Hakimi
- Institut Jean Roget, Université Joseph Fourier, BP170, 38042 Grenoble Cedex 9, France
| | - Steven E. Jacobsen
- Department of Molecular, Cell and Developmental Biology, Howard Hughes Medical Institute, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Richard Cooke
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
| | - Thierry Lagrange
- Laboratoire Génome et Développement de Plantes, Centre National de la Recherche Scientifique/Institut de Recherche pour le Développement/Université de Perpignan 5096, 66860 Perpignan Cedex, France
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Ding L, Han M. GW182 family proteins are crucial for microRNA-mediated gene silencing. Trends Cell Biol 2007; 17:411-6. [PMID: 17766119 DOI: 10.1016/j.tcb.2007.06.003] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Revised: 06/05/2007] [Accepted: 06/07/2007] [Indexed: 11/26/2022]
Abstract
microRNAs (miRNAs) are a conserved class of small RNAs approximately 22 nucleotides in length. They regulate the expression of a large number of mRNAs in animals and plants through the miRNA-induced silencing complex (miRISC). The conserved GW182 family of proteins has recently been identified, and its members have been shown to be associated with miRISC and to be required for miRNA-mediated gene silencing. These proteins have also been localized to processing bodies that are cytoplasmic messenger ribonucleoprotein (mRNP) aggregates containing mRNA decay factors, translational repressors and untranslated mRNAs. Therefore, these properties of GW182 family proteins support the hypothesis that the formation of untranslatable messenger ribonuclear protein particles is one important mechanism of miRNA-mediated gene silencing.
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Affiliation(s)
- Lei Ding
- Howard Hughes Medical Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA
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50
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Jakymiw A, Pauley KM, Li S, Ikeda K, Lian S, Eystathioy T, Satoh M, Fritzler MJ, Chan EKL. The role of GW/P-bodies in RNA processing and silencing. J Cell Sci 2007; 120:1317-23. [PMID: 17401112 DOI: 10.1242/jcs.03429] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
GW bodies, also known as mammalian P-bodies, are cytoplasmic foci involved in the post-transcriptional regulation of eukaryotic gene expression. Recently, GW bodies have been linked to RNA interference and demonstrated to be important for short-interfering-RNA- and microRNA-mediated mRNA decay and translational repression. Evidence indicates that both passenger and guide strands of short-interfering RNA duplexes can localize to GW bodies, thereby indicating that RNA-induced silencing complexes may be activated within these cytoplasmic centers. Formation of GW bodies appears to depend on both specific protein factors and RNA, in particular, microRNA. Work over the past few years has significantly increased our understanding of the biology of GW bodies, revealing that they are specialized cell components that spatially regulate mRNA turnover in various biological processes. The formation of GW bodies appears to depend on both specific protein factors and RNA, in particular, microRNA. Here, we propose a working model for GW body assembly in terms of its relationship to RNA interference. In this process, one or more heteromeric protein complexes accumulate in successive steps into larger ribonucleoprotein structures.
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Affiliation(s)
- Andrew Jakymiw
- Department of Oral Biology, University of Florida, Gainesville, FL 32610, USA
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