1
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Blumenstiel JP. From the cauldron of conflict: Endogenous gene regulation by piRNA and other modes of adaptation enabled by selfish transposable elements. Semin Cell Dev Biol 2024; 164:1-12. [PMID: 38823219 DOI: 10.1016/j.semcdb.2024.05.001] [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: 10/10/2023] [Revised: 04/28/2024] [Accepted: 05/06/2024] [Indexed: 06/03/2024]
Abstract
Transposable elements (TEs) provide a prime example of genetic conflict because they can proliferate in genomes and populations even if they harm the host. However, numerous studies have shown that TEs, though typically harmful, can also provide fuel for adaptation. This is because they code functional sequences that can be useful for the host in which they reside. In this review, I summarize the "how" and "why" of adaptation enabled by the genetic conflict between TEs and hosts. In addition, focusing on mechanisms of TE control by small piwi-interacting RNAs (piRNAs), I highlight an indirect form of adaptation enabled by conflict. In this case, mechanisms of host defense that regulate TEs have been redeployed for endogenous gene regulation. I propose that the genetic conflict released by meiosis in early eukaryotes may have been important because, among other reasons, it spurred evolutionary innovation on multiple interwoven trajectories - on the part of hosts and also embedded genetic parasites. This form of evolution may function as a complexity generating engine that was a critical player in eukaryotic evolution.
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Affiliation(s)
- Justin P Blumenstiel
- Department of Ecology and Evolutionary Biology, University of Kansas, 1200 Sunnyside Avenue, Lawrence, KS 66045, United States.
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2
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Price IF, Wagner JA, Pastore B, Hertz HL, Tang W. C. elegans germ granules sculpt both germline and somatic RNAome. Nat Commun 2023; 14:5965. [PMID: 37749091 PMCID: PMC10520050 DOI: 10.1038/s41467-023-41556-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 09/08/2023] [Indexed: 09/27/2023] Open
Abstract
Germ granules are membrane-less organelles essential for small RNA biogenesis and germline development. Among the conserved properties of germ granules is their association with the nuclear membrane. Recent studies demonstrated that LOTUS domain proteins, EGGD-1 and EGGD-2 (also known as MIP-1 and MIP-2 respectively), promote the formation of perinuclear germ granules in C. elegans. This finding presents a unique opportunity to evaluate the significance of perinuclear localization of germ granules. Here we show that loss of eggd-1 causes the coalescence of germ granules and formation of abnormal cytoplasmic aggregates. Impairment of perinuclear granules affects certain germline classes of small RNAs including Piwi-interacting RNAs. Transcriptome profiling reveals overexpression of spermatogenic and cuticle-related genes in eggd-1 hermaphrodites. We further demonstrate that disruption of germ granules activates HLH-30-mediated transcriptional program in somatic tissues. Collectively, our findings underscore the essential role of EGGD-1 in germ granule organization and reveal an unexpected germ granule-to-soma communication.
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Affiliation(s)
- Ian F Price
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH, 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Jillian A Wagner
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH, 43210, USA
| | - Benjamin Pastore
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH, 43210, USA
- Ohio State Biochemistry Program, The Ohio State University, Columbus, OH, 43210, USA
| | - Hannah L Hertz
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA
- Center for RNA Biology, The Ohio State University, Columbus, OH, 43210, USA
| | - Wen Tang
- Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, 43210, USA.
- Center for RNA Biology, The Ohio State University, Columbus, OH, 43210, USA.
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3
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van Wolfswinkel JC. Insights in piRNA targeting rules. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 15:e1811. [PMID: 37632327 PMCID: PMC10895071 DOI: 10.1002/wrna.1811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/22/2023] [Accepted: 07/06/2023] [Indexed: 08/27/2023]
Abstract
PIWI-interacting RNAs (piRNAs) play an important role in the defense against transposons in the germline and stem cells of animals. To what extent other transcripts are also regulated by piRNAs is an ongoing topic of debate. The amount of sequence complementarity between piRNA and target that is required for effective downregulation of the targeted transcript is guiding in this discussion. Over the years, various methods have been applied to infer targeting requirements from the collections of piRNAs and potential target transcripts, and recent structural studies of the PIWI proteins have provided an additional perspective. In this review, I summarize the findings from these studies and propose a set of requirements that can be used to predict targets to the best of our current abilities. This article is categorized under: Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA-Based Catalysis > RNA-Mediated Cleavage.
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Affiliation(s)
- Josien C van Wolfswinkel
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, Connecticut, USA
- Center for Stem Cell Biology, Yale School of Medicine, New Haven, Connecticut, USA
- Center for RNA Biology and Medicine, Yale School of Medicine, New Haven, Connecticut, USA
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4
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Wu WS, Brown JS, Shiue SC, Chung CJ, Lee DE, Zhang D, Lee HC. Transcriptome-wide analyses of piRNA binding sites suggest distinct mechanisms regulate piRNA binding and silencing in C. elegans. RNA (NEW YORK, N.Y.) 2023; 29:557-569. [PMID: 36737102 PMCID: PMC10158993 DOI: 10.1261/rna.079441.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/25/2022] [Indexed: 05/06/2023]
Abstract
PIWI-interacting RNAs (piRNAs) protect genome integrity by silencing transposon mRNAs and some endogenous mRNAs in various animals. However, C. elegans piRNAs only trigger gene silencing at select predicted targeting sites, suggesting additional cellular mechanisms regulate piRNA silencing. To gain insight into possible mechanisms, we compared the transcriptome-wide predicted piRNA targeting sites to the in vivo piRNA binding sites. Surprisingly, while sequence-based predicted piRNA targeting sites are enriched in 3' UTRs, we found that C. elegans piRNAs preferentially bind to coding regions (CDS) of target mRNAs, leading to preferential production of secondary silencing small RNAs in the CDS. However, our analyses suggest that this CDS binding preference cannot be explained by the action of antisilencing Argonaute CSR-1. Instead, our analyses imply that CSR-1 protects mRNAs from piRNA silencing through two distinct mechanisms-by inhibiting piRNA binding across the entire CSR-1 targeted transcript, and by inhibiting secondary silencing small RNA production locally at CSR-1 bound sites. Together, our work identifies the CDS as the critical region that is uniquely competent for piRNA binding in C. elegans. We speculate the CDS binding preference may have evolved to allow the piRNA pathway to maintain robust recognition of RNA targets in spite of genetic drift. Together, our analyses revealed that distinct mechanisms are responsible for restricting piRNA binding and silencing to achieve proper transcriptome surveillance.
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Affiliation(s)
- Wei-Sheng Wu
- Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Jordan S Brown
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
| | - Sheng-Cian Shiue
- Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Chi-Jung Chung
- Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Dong-En Lee
- Department of Electrical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - Donglei Zhang
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
| | - Heng-Chi Lee
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, Illinois 60637, USA
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5
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Wang X, Ramat A, Simonelig M, Liu MF. Emerging roles and functional mechanisms of PIWI-interacting RNAs. Nat Rev Mol Cell Biol 2023; 24:123-141. [PMID: 36104626 DOI: 10.1038/s41580-022-00528-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 55.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2022] [Indexed: 02/02/2023]
Abstract
PIWI-interacting RNAs (piRNAs) are a class of small non-coding RNAs that associate with proteins of the PIWI clade of the Argonaute family. First identified in animal germ line cells, piRNAs have essential roles in germ line development. The first function of PIWI-piRNA complexes to be described was the silencing of transposable elements, which is crucial for maintaining the integrity of the germ line genome. Later studies provided new insights into the functions of PIWI-piRNA complexes by demonstrating that they regulate protein-coding genes. Recent studies of piRNA biology, including in new model organisms such as golden hamsters, have deepened our understanding of both piRNA biogenesis and piRNA function. In this Review, we discuss the most recent advances in our understanding of piRNA biogenesis, the molecular mechanisms of piRNA function and the emerging roles of piRNAs in germ line development mainly in flies and mice, and in infertility, cancer and neurological diseases in humans.
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Affiliation(s)
- Xin Wang
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
| | - Anne Ramat
- Institute of Human Genetics, University of Montpellier, CNRS, Montpellier, France
| | - Martine Simonelig
- Institute of Human Genetics, University of Montpellier, CNRS, Montpellier, France.
| | - Mo-Fang Liu
- State Key Laboratory of Molecular Biology, Shanghai Key Laboratory of Molecular Andrology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China. .,Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China. .,School of Life Science and Technology, Shanghai Tech University, Shanghai, China.
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6
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Watson OT, Buchmann G, Young P, Lo K, Remnant EJ, Yagound B, Shambrook M, Hill AF, Oldroyd BP, Ashe A. Abundant small RNAs in the reproductive tissues and eggs of the honey bee, Apis mellifera. BMC Genomics 2022; 23:257. [PMID: 35379185 PMCID: PMC8978429 DOI: 10.1186/s12864-022-08478-9] [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: 09/09/2021] [Accepted: 03/17/2022] [Indexed: 11/21/2022] Open
Abstract
Background Polyandrous social insects such as the honey bee are prime candidates for parental manipulation of gene expression in offspring. Although there is good evidence for parent-of-origin effects in honey bees the epigenetic mechanisms that underlie these effects remain a mystery. Small RNA molecules such as miRNAs, piRNAs and siRNAs play important roles in transgenerational epigenetic inheritance and in the regulation of gene expression during development. Results Here we present the first characterisation of small RNAs present in honey bee reproductive tissues: ovaries, spermatheca, semen, fertilised and unfertilised eggs, and testes. We show that semen contains fewer piRNAs relative to eggs and ovaries, and that piRNAs and miRNAs which map antisense to genes involved in DNA regulation and developmental processes are differentially expressed between tissues. tRNA fragments are highly abundant in semen and have a similar profile to those seen in the semen of other animals. Intriguingly we also find abundant piRNAs that target the sex determination locus, suggesting that piRNAs may play a role in honey bee sex determination. Conclusions We conclude that small RNAs may play a fundamental role in honey bee gametogenesis and reproduction and provide a plausible mechanism for parent-of-origin effects on gene expression and reproductive physiology. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08478-9.
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Affiliation(s)
- Owen T Watson
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Gabriele Buchmann
- BEE Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Paul Young
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute NSW 2010, Darlinghurst, Australia
| | - Kitty Lo
- School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, 2006, Australia
| | - Emily J Remnant
- BEE Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Boris Yagound
- BEE Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia
| | - Mitch Shambrook
- Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, 3086, Australia
| | - Andrew F Hill
- Department of Biochemistry and Chemistry, School of Agriculture, Biomedicine and Environment, La Trobe Institute for Molecular Science, La Trobe University, Bundoora, Victoria, 3086, Australia.,Institute for Health and Sport, Victoria University, Footscray, VIC, Australia
| | - Benjamin P Oldroyd
- BEE Laboratory, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, 2006, Australia. .,Wissenschaftskolleg zu Berlin, Wallotstrasse 19, 14193, Berlin, Germany.
| | - Alyson Ashe
- School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW, 2006, Australia.
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7
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Davis MB, Jash E, Chawla B, Haines RA, Tushman LE, Troll R, Csankovszki G. Dual roles for nuclear RNAi Argonautes in Caenorhabditis elegans dosage compensation. Genetics 2022; 221:6540857. [PMID: 35234908 PMCID: PMC9071528 DOI: 10.1093/genetics/iyac033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/21/2022] [Indexed: 11/14/2022] Open
Abstract
Dosage compensation involves chromosome-wide gene regulatory mechanisms which impact higher order chromatin structure and are crucial for organismal health. Using a genetic approach, we identified Argonaute genes which promote dosage compensation in Caenorhabditis elegans. Dosage compensation in C. elegans hermaphrodites is initiated by the silencing of xol-1 and subsequent activation of the dosage compensation complex which binds to both hermaphrodite X chromosomes and reduces transcriptional output by half. A hallmark phenotype of dosage compensation mutants is decondensation of the X chromosomes. We characterized this phenotype in Argonaute mutants using X chromosome paint probes and fluorescence microscopy. We found that while nuclear Argonaute mutants hrde-1 and nrde-3, as well as mutants for the piRNA Argonaute prg-1, exhibit derepression of xol-1 transcripts, they also affect X chromosome condensation in a xol-1-independent manner. We also characterized the physiological contribution of Argonaute genes to dosage compensation using genetic assays and found that hrde-1 and nrde-3 contribute to healthy dosage compensation both upstream and downstream of xol-1.
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Affiliation(s)
- Michael B Davis
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Eshna Jash
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Bahaar Chawla
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rebecca A Haines
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Lillian E Tushman
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ryan Troll
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Györgyi Csankovszki
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA,Corresponding author: Department of Molecular, Cellular, and Developmental Biology, University of Michigan, 1105 N. University Ave, Ann Arbor, MI 48109-1085, USA.
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8
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Chen X, Rechavi O. Plant and animal small RNA communications between cells and organisms. Nat Rev Mol Cell Biol 2022; 23:185-203. [PMID: 34707241 PMCID: PMC9208737 DOI: 10.1038/s41580-021-00425-y] [Citation(s) in RCA: 69] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 01/09/2023]
Abstract
Since the discovery of eukaryotic small RNAs as the main effectors of RNA interference in the late 1990s, diverse types of endogenous small RNAs have been characterized, most notably microRNAs, small interfering RNAs (siRNAs) and PIWI-interacting RNAs (piRNAs). These small RNAs associate with Argonaute proteins and, through sequence-specific gene regulation, affect almost every major biological process. Intriguing features of small RNAs, such as their mechanisms of amplification, rapid evolution and non-cell-autonomous function, bestow upon them the capacity to function as agents of intercellular communications in development, reproduction and immunity, and even in transgenerational inheritance. Although there are many types of extracellular small RNAs, and despite decades of research, the capacity of these molecules to transmit signals between cells and between organisms is still highly controversial. In this Review, we discuss evidence from different plants and animals that small RNAs can act in a non-cell-autonomous manner and even exchange information between species. We also discuss mechanistic insights into small RNA communications, such as the nature of the mobile agents, small RNA signal amplification during transit, signal perception and small RNA activity at the destination.
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Affiliation(s)
- Xuemei Chen
- Department of Botany and Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.
| | - Oded Rechavi
- Department of Neurobiology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel. .,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
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9
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Dysregulation of Human Somatic piRNA Expression in Parkinson's Disease Subtypes and Stages. Int J Mol Sci 2022; 23:ijms23052469. [PMID: 35269612 PMCID: PMC8910154 DOI: 10.3390/ijms23052469] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/14/2022] [Accepted: 02/17/2022] [Indexed: 02/04/2023] Open
Abstract
Piwi interacting RNAs (piRNAs) are small non-coding single-stranded RNA species 20–31 nucleotides in size generated from distinct loci. In germline tissues, piRNAs are amplified via a “ping-pong cycle” to produce secondary piRNAs, which act in transposon silencing. In contrast, the role of somatic-derived piRNAs remains obscure. Here, we investigated the identity and distribution of piRNAs in human somatic tissues to determine their function and potential role in Parkinson’s disease (PD). Human datasets were curated from the Gene Expression Omnibus (GEO) database and a workflow was developed to identify piRNAs, which revealed 902 somatic piRNAs of which 527 were expressed in the brain. These were mainly derived from chromosomes 1, 11, and 19 compared to the germline tissues, which were from 15 and 19. Approximately 20% of somatic piRNAs mapped to transposon 3′ untranslated regions (UTRs), but a large proportion were sensed to the transcript in contrast to germline piRNAs. Gene set enrichment analysis suggested that somatic piRNAs function in neurodegenerative disease. piRNAs undergo dysregulation in different PD subtypes (PD and Parkinson’s disease dementia (PDD)) and stages (premotor and motor). piR-has-92056, piR-hsa-150797, piR-hsa-347751, piR-hsa-1909905, piR-hsa-2476630, and piR-hsa-2834636 from blood small extracellular vesicles were identified as novel biomarkers for PD diagnosis using a sparse partial least square discriminant analysis (sPLS-DA) (accuracy: 92%, AUC = 0.89). This study highlights a role for piRNAs in PD and provides tools for novel biomarker development.
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10
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Cornes E, Bourdon L, Singh M, Mueller F, Quarato P, Wernersson E, Bienko M, Li B, Cecere G. piRNAs initiate transcriptional silencing of spermatogenic genes during C. elegans germline development. Dev Cell 2022; 57:180-196.e7. [PMID: 34921763 PMCID: PMC8796119 DOI: 10.1016/j.devcel.2021.11.025] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/02/2021] [Accepted: 11/26/2021] [Indexed: 12/22/2022]
Abstract
Eukaryotic genomes harbor invading transposable elements that are silenced by PIWI-interacting RNAs (piRNAs) to maintain genome integrity in animal germ cells. However, whether piRNAs also regulate endogenous gene expression programs remains unclear. Here, we show that C. elegans piRNAs trigger the transcriptional silencing of hundreds of spermatogenic genes during spermatogenesis, promoting sperm differentiation and function. This silencing signal requires piRNA-dependent small RNA biogenesis and loading into downstream nuclear effectors, which correlates with the dynamic reorganization of two distinct perinuclear biomolecular condensates present in germ cells. In addition, the silencing capacity of piRNAs is temporally counteracted by the Argonaute CSR-1, which targets and licenses spermatogenic gene transcription. The spatial and temporal overlap between these opposing small RNA pathways contributes to setting up the timing of the spermatogenic differentiation program. Thus, our work identifies a prominent role for piRNAs as direct regulators of endogenous transcriptional programs during germline development and gamete differentiation.
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Affiliation(s)
- Eric Cornes
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France
| | - Loan Bourdon
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France
| | - Meetali Singh
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France
| | - Florian Mueller
- Imaging and Modeling Unit, Institut Pasteur, UMR 3691 CNRS, C3BI USR 3756 IP CNRS, Paris, France
| | - Piergiuseppe Quarato
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France
| | - Erik Wernersson
- Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17165, Sweden; Science for Life Laboratory, Tomtebodavägen 23A, Stockholm 17165, Sweden
| | - Magda Bienko
- Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm 17165, Sweden; Science for Life Laboratory, Tomtebodavägen 23A, Stockholm 17165, Sweden
| | - Blaise Li
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France; Bioinformatics and Biostatistics Hub, Department of Computational Biology, Institut Pasteur, USR 3756, CNRS, Paris 75015, France
| | - Germano Cecere
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris 75015, France.
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11
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Pastore B, Hertz HL, Tang W. Comparative analysis of piRNA sequences, targets and functions in nematodes. RNA Biol 2022; 19:1276-1292. [PMID: 36412988 PMCID: PMC9683057 DOI: 10.1080/15476286.2022.2149170] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Piwi proteins and Piwi-interacting RNAs (piRNAs) are best known for their roles in suppressing transposons and promoting fertility. Yet piRNA biogenesis and its mechanisms of action differ widely between distantly related species. To better understand the evolution of piRNAs, we characterized the piRNA pathway in C. briggsae, a sibling species of the model organism C. elegans. Our analyses define 25,883 piRNA producing-loci in C. briggsae. piRNA sequences in C. briggsae are extremely divergent from their counterparts in C. elegans, yet both species adopt similar genomic organization that drive piRNA expression. By examining production of Piwi-mediated secondary small RNAs, we identified a set of protein-coding genes that are evolutionarily conserved piRNA targets. In contrast to C. elegans, small RNAs targeting ribosomal RNAs or histone transcripts are not hyper-accumulated in C. briggsae Piwi mutants. Instead, we found that transcripts with few introns are prone to small RNA overamplification. Together our work highlights evolutionary conservation and divergence of the nematode piRNA pathway and provides insights into its role in endogenous gene regulation.
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Affiliation(s)
- Benjamin Pastore
- Department of Biological Chemistry and Pharmacology, The Ohio State University,Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA,Center for RNA Biology, Ohio State University, Columbus, OH, USA
| | - Hannah L. Hertz
- Department of Biological Chemistry and Pharmacology, The Ohio State University,Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA
| | - Wen Tang
- Department of Biological Chemistry and Pharmacology, The Ohio State University,Department of Biological Chemistry and Pharmacology, Ohio State University, Columbus, OH, USA,CONTACT Wen Tang Department of Biological Chemistry and Pharmacology, The Ohio State University, Columbus, OH, USA
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12
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Halbach R, Miesen P. Functional Analysis of Individual piRNAs in Aedes aegypti Cells and Embryos Using Antisense Oligonucleotides. Methods Mol Biol 2022; 2509:3-22. [PMID: 35796954 DOI: 10.1007/978-1-0716-2380-0_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In insects, PIWI-interacting (pi)RNAs fulfill versatile regulatory functions inside and outside the germline, including posttranscriptional repression of transposable elements and regulation of gene expression. Canonically, piRNAs act-and have been studied-as a conglomerate of several thousand sequences that cooperatively silence target RNAs. Interestingly, however, an increasing number of studies have demonstrated that individual piRNAs can have profound biological activity as a unique piRNA sequence. Prime examples are the tapiR1 and 2 piRNAs, which mediate target RNA degradation in the developing embryo of Aedes mosquitoes. To study such outstanding individual piRNA species, we describe here a method to interfere with RNA target silencing using antisense oligonucleotides in cell culture as well as in mosquito pre-blastoderm embryos. Although the method has been established for Aedes mosquitoes, it can likely be adapted for use in other invertebrate species as well.
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Affiliation(s)
- Rebecca Halbach
- Department of Medical Microbiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands
| | - Pascal Miesen
- Department of Medical Microbiology, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.
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13
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Wang J, Shi Y, Zhou H, Zhang P, Song T, Ying Z, Yu H, Li Y, Zhao Y, Zeng X, He S, Chen R. piRBase: integrating piRNA annotation in all aspects. Nucleic Acids Res 2021; 50:D265-D272. [PMID: 34871445 PMCID: PMC8728152 DOI: 10.1093/nar/gkab1012] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 10/10/2021] [Accepted: 10/13/2021] [Indexed: 02/05/2023] Open
Abstract
Piwi-interacting RNAs are a type of small noncoding RNA that have various functions. piRBase is a manually curated resource focused on assisting piRNA functional analysis. piRBase release v3.0 is committed to providing more comprehensive piRNA related information. The latest release covers >181 million unique piRNA sequences, including 440 datasets from 44 species. More disease-related piRNAs and piRNA targets have been collected and displayed. The regulatory relationships between piRNAs and targets have been visualized. In addition to the reuse and expansion of the content in the previous version, the latest version has additional new content, including gold standard piRNA sets, piRNA clusters, piRNA variants, splicing-junction piRNAs, and piRNA expression data. In addition, the entire web interface has been redesigned to provide a better experience for users. piRBase release v3.0 is free to access, browse, search, and download at http://bigdata.ibp.ac.cn/piRBase.
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Affiliation(s)
- Jiajia Wang
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yirong Shi
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Honghong Zhou
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Zhang
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,National Genomics Data Center, Chinese Academy of Sciences, Beijing 100101, China
| | - Tingrui Song
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Zhiye Ying
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
| | - Haopeng Yu
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
| | - Yanyan Li
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi Zhao
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of Intelligent Information Processing, Advanced Computer Research Center, Institute of Computing Technology, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiaoxi Zeng
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China
| | - Shunmin He
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.,National Genomics Data Center, Chinese Academy of Sciences, Beijing 100101, China
| | - Runsheng Chen
- West China Biomedical Big Data Center, West China Hospital, Sichuan University, Chengdu 610041, China.,Med-X Center for Informatics, Sichuan University, Chengdu 610041, China.,Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,National Genomics Data Center, Chinese Academy of Sciences, Beijing 100101, China.,Guangdong Geneway Decoding Bio-Tech Co. Ltd, Foshan 528316, China
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14
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Cecere G. Small RNAs in epigenetic inheritance: from mechanisms to trait transmission. FEBS Lett 2021; 595:2953-2977. [PMID: 34671979 PMCID: PMC9298081 DOI: 10.1002/1873-3468.14210] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 10/08/2021] [Accepted: 10/18/2021] [Indexed: 01/02/2023]
Abstract
Inherited information is transmitted to progeny primarily by the genome through the gametes. However, in recent years, epigenetic inheritance has been demonstrated in several organisms, including animals. Although it is clear that certain post‐translational histone modifications, DNA methylation, and noncoding RNAs regulate epigenetic inheritance, the molecular mechanisms responsible for epigenetic inheritance are incompletely understood. This review focuses on the role of small RNAs in transmitting epigenetic information across generations in animals. Examples of documented cases of transgenerational epigenetic inheritance are discussed, from the silencing of transgenes to the inheritance of complex traits, such as fertility, stress responses, infections, and behavior. Experimental evidence supporting the idea that small RNAs are epigenetic molecules capable of transmitting traits across generations is highlighted, focusing on the mechanisms by which small RNAs achieve such a function. Just as the role of small RNAs in epigenetic processes is redefining the concept of inheritance, so too our understanding of the molecular pathways and mechanisms that govern epigenetic inheritance in animals is radically changing.
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Affiliation(s)
- Germano Cecere
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR3738, CNRS, Paris, France
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15
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Gonzalez LE, Tang X, Lin H. Maternal Piwi Regulates Primordial Germ Cell Development to Ensure the Fertility of Female Progeny in Drosophila. Genetics 2021; 219:6303617. [PMID: 34142134 DOI: 10.1093/genetics/iyab091] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 06/02/2021] [Indexed: 12/18/2022] Open
Abstract
In many animals, germline development is initiated by proteins and RNAs that are expressed maternally. PIWI proteins and their associated small noncoding PIWI-interacting RNAs (piRNAs), which guide PIWI to target RNAs by base-pairing, are among the maternal components deposited into the germline of the Drosophila early embryo. Piwi has been extensively studied in the adult ovary and testis, where it is required for transposon suppression, germline stem cell self-renewal, and fertility. Consequently, loss of Piwi in the adult ovary using piwi-null alleles or knockdown from early oogenesis results in complete sterility, limiting investigation into possible embryonic functions of maternal Piwi. In this study, we show that the maternal Piwi protein persists in the embryonic germline through gonad coalescence, suggesting that maternal Piwi can regulate germline development beyond early embryogenesis. Using a maternal knockdown strategy, we find that maternal Piwi is required for the fertility and normal gonad morphology of female, but not male, progeny. Following maternal piwi knockdown, transposons were mildly derepressed in the early embryo but were fully repressed in the ovaries of adult progeny. Furthermore, the maternal piRNA pool was diminished, reducing the capacity of the PIWI/piRNA complex to target zygotic genes during embryogenesis. Examination of embryonic germ cell proliferation and ovarian gene expression showed that the germline of female progeny was partially masculinized by maternal piwi knockdown. Our study reveals a novel role for maternal Piwi in the germline development of female progeny and suggests that the PIWI/piRNA pathway is involved in germline sex determination in Drosophila.
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Affiliation(s)
- Lauren E Gonzalez
- Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06519, USA.,Department of Genetics, Yale School of Medicine, New Haven, CT 06519, USA
| | - Xiongzhuo Tang
- Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06519, USA.,Department of Cell Biology, Yale School of Medicine, New Haven, CT 06519, USA
| | - Haifan Lin
- Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06519, USA.,Department of Cell Biology, Yale School of Medicine, New Haven, CT 06519, USA
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16
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Chen P, Kotov AA, Godneeva BK, Bazylev SS, Olenina LV, Aravin AA. piRNA-mediated gene regulation and adaptation to sex-specific transposon expression in D. melanogaster male germline. Genes Dev 2021; 35:914-935. [PMID: 33985970 PMCID: PMC8168559 DOI: 10.1101/gad.345041.120] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 04/08/2021] [Indexed: 12/19/2022]
Abstract
Small noncoding piRNAs act as sequence-specific guides to repress complementary targets in Metazoa. Prior studies in Drosophila ovaries have demonstrated the function of the piRNA pathway in transposon silencing and therefore genome defense. However, the ability of the piRNA program to respond to different transposon landscapes and the role of piRNAs in regulating host gene expression remain poorly understood. Here, we comprehensively analyzed piRNA expression and defined the repertoire of their targets in Drosophila melanogaster testes. Comparison of piRNA programs between sexes revealed sexual dimorphism in piRNA programs that parallel sex-specific transposon expression. Using a novel bioinformatic pipeline, we identified new piRNA clusters and established complex satellites as dual-strand piRNA clusters. While sharing most piRNA clusters, the two sexes employ them differentially to combat the sex-specific transposon landscape. We found two piRNA clusters that produce piRNAs antisense to four host genes in testis, including CG12717/pirate, a SUMO protease gene. piRNAs encoded on the Y chromosome silence pirate, but not its paralog, to exert sex- and paralog-specific gene regulation. Interestingly, pirate is targeted by endogenous siRNAs in a sibling species, Drosophila mauritiana, suggesting distinct but related silencing strategies invented in recent evolution to regulate a conserved protein-coding gene.
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Affiliation(s)
- Peiwei Chen
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California 91125, USA
| | - Alexei A Kotov
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute," Moscow 123182, Russia
| | - Baira K Godneeva
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California 91125, USA
| | - Sergei S Bazylev
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute," Moscow 123182, Russia
| | - Ludmila V Olenina
- Institute of Molecular Genetics of National Research Center "Kurchatov Institute," Moscow 123182, Russia
| | - Alexei A Aravin
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California 91125, USA
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17
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Placentino M, de Jesus Domingues AM, Schreier J, Dietz S, Hellmann S, de Albuquerque BFM, Butter F, Ketting RF. Intrinsically disordered protein PID-2 modulates Z granules and is required for heritable piRNA-induced silencing in the Caenorhabditis elegans embryo. EMBO J 2021; 40:e105280. [PMID: 33231880 PMCID: PMC7849312 DOI: 10.15252/embj.2020105280] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 09/25/2020] [Accepted: 10/02/2020] [Indexed: 12/12/2022] Open
Abstract
In Caenorhabditis elegans, the piRNA (21U RNA) pathway is required to establish proper gene regulation and an immortal germline. To achieve this, PRG-1-bound 21U RNAs trigger silencing mechanisms mediated by RNA-dependent RNA polymerase (RdRP)-synthetized 22G RNAs. This silencing can become PRG-1-independent and heritable over many generations, a state termed RNA-induced epigenetic gene silencing (RNAe). How and when RNAe is established, and how it is maintained, is not known. We show that maternally provided 21U RNAs can be sufficient for triggering RNAe in embryos. Additionally, we identify PID-2, a protein containing intrinsically disordered regions (IDRs), as a factor required for establishing and maintaining RNAe. PID-2 interacts with two newly identified and partially redundant eTudor domain-containing proteins, PID-4 and PID-5. PID-5 has an additional domain related to the X-prolyl aminopeptidase APP-1, and binds APP-1, implicating potential N-terminal proteolysis in RNAe. All three proteins are required for germline immortality, localize to perinuclear foci, affect size and appearance of RNA inheritance-linked Z granules, and are required for balancing of 22G RNA populations. Overall, our study identifies three new proteins with crucial functions in C. elegans small RNA silencing.
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Affiliation(s)
- Maria Placentino
- Biology of Non‐coding RNA GroupInstitute of Molecular Biology (IMB)MainzGermany
- International PhD Programme on Gene Regulation, Epigenetics & Genome StabilityMainzGermany
| | | | - Jan Schreier
- Biology of Non‐coding RNA GroupInstitute of Molecular Biology (IMB)MainzGermany
- International PhD Programme on Gene Regulation, Epigenetics & Genome StabilityMainzGermany
| | - Sabrina Dietz
- International PhD Programme on Gene Regulation, Epigenetics & Genome StabilityMainzGermany
- Quantitative Proteomics GroupInstitute of Molecular Biology (IMB)MainzGermany
| | - Svenja Hellmann
- Biology of Non‐coding RNA GroupInstitute of Molecular Biology (IMB)MainzGermany
| | - Bruno FM de Albuquerque
- Biology of Non‐coding RNA GroupInstitute of Molecular Biology (IMB)MainzGermany
- Graduate Program in Areas of Basic and Applied BiologyUniversity of PortoPortoPortugal
| | - Falk Butter
- Quantitative Proteomics GroupInstitute of Molecular Biology (IMB)MainzGermany
| | - René F Ketting
- Biology of Non‐coding RNA GroupInstitute of Molecular Biology (IMB)MainzGermany
- Institute of Developmental Biology and NeurobiologyJohannses Gutenberg UniversityMainzGermany
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18
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Ramat A, Simonelig M. Functions of PIWI Proteins in Gene Regulation: New Arrows Added to the piRNA Quiver. Trends Genet 2021; 37:188-200. [DOI: 10.1016/j.tig.2020.08.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 08/05/2020] [Accepted: 08/18/2020] [Indexed: 12/14/2022]
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19
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Wang C, Lin H. Roles of piRNAs in transposon and pseudogene regulation of germline mRNAs and lncRNAs. Genome Biol 2021; 22:27. [PMID: 33419460 PMCID: PMC7792047 DOI: 10.1186/s13059-020-02221-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 12/07/2020] [Indexed: 12/28/2022] Open
Abstract
PIWI proteins, a subfamily of PAZ/PIWI Domain family RNA-binding proteins, are best known for their function in silencing transposons and germline development by partnering with small noncoding RNAs called PIWI-interacting RNAs (piRNAs). However, recent studies have revealed multifaceted roles of the PIWI-piRNA pathway in regulating the expression of other major classes of RNAs in germ cells. In this review, we summarize how PIWI proteins and piRNAs regulate the expression of many disparate RNAs, describing a highly complex global genomic regulatory relationship at the RNA level through which piRNAs functionally connect all major constituents of the genome in the germline.
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Affiliation(s)
- Chen Wang
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Haifan Lin
- Yale Stem Cell Center and Department of Cell Biology, Yale University School of Medicine, New Haven, CT, 06519, USA.
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20
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Abstract
A diversity of gene regulatory mechanisms drives the changes in gene expression required for animal development. Here, we discuss the developmental roles of a class of gene regulatory factors composed of a core protein subunit of the Argonaute family and a 21-26-nucleotide RNA cofactor. These represent ancient regulatory complexes, originally evolved to repress genomic parasites such as transposons, viruses and retroviruses. However, over the course of evolution, small RNA-guided pathways have expanded and diversified, and they play multiple roles across all eukaryotes. Pertinent to this review, Argonaute and small RNA-mediated regulation has acquired numerous functions that affect all aspects of animal life. The regulatory function is provided by the Argonaute protein and its interactors, while the small RNA provides target specificity, guiding the Argonaute to a complementary RNA. C. elegans has 19 different, functional Argonautes, defining distinct yet interconnected pathways. Each Argonaute binds a relatively well-defined class of small RNA with distinct molecular properties. A broad classification of animal small RNA pathways distinguishes between two groups: (i) the microRNA pathway is involved in repressing relatively specific endogenous genes and (ii) the other small RNA pathways, which effectively act as a genomic immune system to primarily repress expression of foreign or "non-self" RNA while maintaining correct endogenous gene expression. microRNAs play prominent direct roles in all developmental stages, adult physiology and lifespan. The other small RNA pathways act primarily in the germline, but their impact extends far beyond, into embryogenesis and adult physiology, and even to subsequent generations. Here, we review the mechanisms and developmental functions of the diverse small RNA pathways of C. elegans.
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Affiliation(s)
| | - Luisa Cochella
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Vienna, Austria.
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21
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Wang J, Zhang P, Lu Y, Li Y, Zheng Y, Kan Y, Chen R, He S. piRBase: a comprehensive database of piRNA sequences. Nucleic Acids Res 2020; 47:D175-D180. [PMID: 30371818 PMCID: PMC6323959 DOI: 10.1093/nar/gky1043] [Citation(s) in RCA: 137] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 10/22/2018] [Indexed: 12/25/2022] Open
Abstract
PIWI-interacting RNAs are a class of small RNAs that is most abundantly expressed in animal germline. Substantial research is going on to reveal the functions of piRNAs in the epigenetic and post-transcriptional regulation of transposons and genes. To collect and annotate these data, we developed piRBase, a database assisting piRNA functional study. Since its launch in 2014, piRBase has integrated 264 data sets from 21 organisms, and the number of collected piRNAs has reached 173 million. The latest piRBase release (v2.0, 2018) was more focused on the comprehensive annotation of piRNA sequences, as well as the increasing number of piRNAs. In addition, piRBase release v2.0 also contained the potential information of piRNA targets and disease related piRNA. All datasets in piRBase is free to access, and available for browse, search and bulk downloads at http://www.regulatoryrna.org/database/piRNA/.
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Affiliation(s)
- Jiajia Wang
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng Zhang
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yiping Lu
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001,China
| | - Yanyan Li
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Science, Beijing 100049, China
| | - Yu Zheng
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,University of Chinese Academy of Science, Beijing 100049, China
| | - Yunchao Kan
- China-UK-NYNU-RRes Joint Laboratory of insect biology, Henan Key Laboratory of Insect Biology in Funiu Mountain, Nanyang Normal University, Nanyang, Henan 473061,China
| | - Runsheng Chen
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Shunmin He
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
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22
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Wu WS, Brown JS, Chen TT, Chu YH, Huang WC, Tu S, Lee HC. piRTarBase: a database of piRNA targeting sites and their roles in gene regulation. Nucleic Acids Res 2020; 47:D181-D187. [PMID: 30357353 PMCID: PMC6323935 DOI: 10.1093/nar/gky956] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 10/04/2018] [Indexed: 12/12/2022] Open
Abstract
PIWI-interacting RNAs (piRNAs) are a class of small noncoding RNAs that guard animal genomes against mutation by silencing transposons. In addition, recent studies have reported that piRNAs silence various endogenous genes. Tens of thousands of distinct piRNAs made in animals do not pair well to transposons and currently the functions and targets of piRNAs are largely unexplored. piRTarBase provides a user-friendly interface to access both predicted and experimentally identified piRNA targeting sites in Caenorhabditis elegans. The user can input genes of interest and retrieve a list of piRNA targeting sites on the input genes. Alternatively, the user can input a piRNA and retrieve a list of its mRNA targets. Additionally, piRTarBase integrates published mRNA and small RNA sequencing data, which will help users identify biologically relevant targeting events. Importantly, our analyses suggest that the piRNA sites found by both predictive and experimental approaches are more likely to exhibit silencing effects on their targets than each method alone. Taken together, piRTarBase offers an integrative platform that will help users to identify functional piRNA target sites by evaluating various information. piRTarBase is freely available for academic use at http://cosbi6.ee.ncku.edu.tw/piRTarBase/.
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Affiliation(s)
- Wei-Sheng Wu
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Jordan S Brown
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Tsung-Te Chen
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Han Chu
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Wei-Che Huang
- Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Shikui Tu
- Department of Computer Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Heng-Chi Lee
- Department of Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
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23
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Barucci G, Cornes E, Singh M, Li B, Ugolini M, Samolygo A, Didier C, Dingli F, Loew D, Quarato P, Cecere G. Small-RNA-mediated transgenerational silencing of histone genes impairs fertility in piRNA mutants. Nat Cell Biol 2020; 22:235-245. [PMID: 32015436 PMCID: PMC7272227 DOI: 10.1038/s41556-020-0462-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 01/05/2020] [Indexed: 11/09/2022]
Abstract
PIWI-interacting RNAs (piRNAs) promote fertility in many animals. However, whether this is due to their conserved role in repressing repetitive elements (REs) remains unclear. Here, we show that the progressive loss of fertility in Caenorhabditis elegans lacking piRNAs is not caused by derepression of REs or other piRNA targets but, rather, is mediated by epigenetic silencing of all of the replicative histone genes. In the absence of piRNAs, downstream components of the piRNA pathway relocalize from germ granules and piRNA targets to histone mRNAs to synthesize antisense small RNAs (sRNAs) and induce transgenerational silencing. Removal of the downstream components of the piRNA pathway restores histone mRNA expression and fertility in piRNA mutants, and the inheritance of histone sRNAs in wild-type worms adversely affects their fertility for multiple generations. We conclude that sRNA-mediated silencing of histone genes impairs the fertility of piRNA mutants and may serve to maintain piRNAs across evolution.
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Affiliation(s)
- Giorgia Barucci
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
- Sorbonne Université, Collège doctoral, Paris, France
| | - Eric Cornes
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
| | - Meetali Singh
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
| | - Blaise Li
- Bioinformatics and Biostatistics Hub, C3BI, Institut Pasteur, USR 3756, CNRS, Paris, France
| | - Martino Ugolini
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
- Scuola Normale Superiore, Pisa, Italy
| | - Aleksei Samolygo
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
- Moscow Institute of Physics and Technology, Moscow, Russia
| | - Celine Didier
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
| | - Florent Dingli
- Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL Research University, Paris, France
| | - Damarys Loew
- Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL Research University, Paris, France
| | - Piergiuseppe Quarato
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France
- Sorbonne Université, Collège doctoral, Paris, France
| | - Germano Cecere
- Mechanisms of Epigenetic Inheritance, Department of Developmental and Stem Cell Biology, Institut Pasteur, UMR 3738, CNRS, Paris, France.
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24
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Dechaud C, Volff JN, Schartl M, Naville M. Sex and the TEs: transposable elements in sexual development and function in animals. Mob DNA 2019; 10:42. [PMID: 31700550 PMCID: PMC6825717 DOI: 10.1186/s13100-019-0185-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/21/2019] [Indexed: 12/23/2022] Open
Abstract
Transposable elements are endogenous DNA sequences able to integrate into and multiply within genomes. They constitute a major source of genetic innovations, as they can not only rearrange genomes but also spread ready-to-use regulatory sequences able to modify host gene expression, and even can give birth to new host genes. As their evolutionary success depends on their vertical transmission, transposable elements are intrinsically linked to reproduction. In organisms with sexual reproduction, this implies that transposable elements have to manifest their transpositional activity in germ cells or their progenitors. The control of sexual development and function can be very versatile, and several studies have demonstrated the implication of transposable elements in the evolution of sex. In this review, we report the functional and evolutionary relationships between transposable elements and sexual reproduction in animals. In particular, we highlight how transposable elements can influence expression of sexual development genes, and how, reciprocally, they are tightly controlled in gonads. We also review how transposable elements contribute to the organization, expression and evolution of sexual development genes and sex chromosomes. This underscores the intricate co-evolution between host functions and transposable elements, which regularly shift from a parasitic to a domesticated status useful to the host.
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Affiliation(s)
- Corentin Dechaud
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d’Italie, F-69364 Lyon, France
| | - Jean-Nicolas Volff
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d’Italie, F-69364 Lyon, France
| | - Manfred Schartl
- Entwicklungsbiochemie, Biozentrum, Universität Würzburg, Würzburg, Germany
- The Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX USA
| | - Magali Naville
- Institut de Genomique Fonctionnelle de Lyon, Univ Lyon, CNRS UMR 5242, Ecole Normale Superieure de Lyon, Universite Claude Bernard Lyon 1, 46 allee d’Italie, F-69364 Lyon, France
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25
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Ouyang JPT, Folkmann A, Bernard L, Lee CY, Seroussi U, Charlesworth AG, Claycomb JM, Seydoux G. P Granules Protect RNA Interference Genes from Silencing by piRNAs. Dev Cell 2019; 50:716-728.e6. [PMID: 31402283 PMCID: PMC6764750 DOI: 10.1016/j.devcel.2019.07.026] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 07/07/2019] [Accepted: 07/26/2019] [Indexed: 01/12/2023]
Abstract
P granules are perinuclear condensates in C. elegans germ cells proposed to serve as hubs for self/non-self RNA discrimination by Argonautes. We report that a mutant (meg-3 meg-4) that does not assemble P granules in primordial germ cells loses competence for RNA-interference over several generations and accumulates silencing small RNAs against hundreds of endogenous genes, including the RNA-interference genes rde-11 and sid-1. In wild type, rde-11 and sid-1 transcripts are heavily targeted by piRNAs and accumulate in P granules but maintain expression. In the primordial germ cells of meg-3 meg-4 mutants, rde-11 and sid-1 transcripts disperse in the cytoplasm with the small RNA biogenesis machinery, become hyper-targeted by secondary sRNAs, and are eventually silenced. Silencing requires the PIWI-class Argonaute PRG-1 and the nuclear Argonaute HRDE-1 that maintains trans-generational silencing of piRNA targets. These observations support a "safe harbor" model for P granules in protecting germline transcripts from piRNA-initiated silencing.
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Affiliation(s)
- John Paul T Ouyang
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Andrew Folkmann
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Lauren Bernard
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Chih-Yung Lee
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Uri Seroussi
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | | | - Julie M Claycomb
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Geraldine Seydoux
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Crysnanto D, Obbard DJ. Widespread gene duplication and adaptive evolution in the RNA interference pathways of the Drosophila obscura group. BMC Evol Biol 2019; 19:99. [PMID: 31068148 PMCID: PMC6505081 DOI: 10.1186/s12862-019-1425-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Accepted: 04/18/2019] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND RNA interference (RNAi) related pathways provide defense against viruses and transposable elements, and have been implicated in the suppression of meiotic drive elements. Genes in these pathways often exhibit high levels of adaptive substitution, and over longer timescales show gene duplication and loss-most likely as a consequence of their role in mediating conflict with these parasites. This is particularly striking for Argonaute 2 (Ago2), which is ancestrally the key effector of antiviral RNAi in insects, but has repeatedly formed new testis-specific duplicates in the recent history of the obscura species-group of Drosophila. RESULTS Here we take advantage of publicly available genomic and transcriptomic data to identify six further RNAi-pathway genes that have duplicated in this clade of Drosophila, and examine their evolutionary history. As seen for Ago2, we observe high levels of adaptive amino-acid substitution and changes in sex-biased expression in many of the paralogs. However, our phylogenetic analysis suggests that co-duplications of the RNAi machinery were not synchronous, and our expression analysis fails to identify consistent male-specific expression. CONCLUSIONS These results confirm that RNAi genes, including genes of the antiviral and piRNA pathways, have undergone multiple independent duplications and that their history has been particularly labile within the obscura group. However, they also suggest that the selective pressures driving these changes have not been consistent, implying that more than one selective agent may be responsible.
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Affiliation(s)
- Danang Crysnanto
- Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, UK
- Animal Genomics, ETH Zurich, Zurich, Switzerland
| | - Darren J. Obbard
- Institute of Evolutionary Biology, University of Edinburgh, Charlotte Auerbach Road, Edinburgh, UK
- Centre for Infection, Evolution and Immunity, University of Edinburgh, Edinburgh, UK
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27
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Perez MF, Lehner B. Intergenerational and transgenerational epigenetic inheritance in animals. Nat Cell Biol 2019; 21:143-151. [PMID: 30602724 DOI: 10.1038/s41556-018-0242-9] [Citation(s) in RCA: 287] [Impact Index Per Article: 57.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/29/2018] [Indexed: 12/12/2022]
Abstract
Animals transmit not only DNA but also other molecules, such as RNA, proteins and metabolites, to their progeny via gametes. It is currently unclear to what extent these molecules convey information between generations and whether this information changes according to their physiological state and environment. Here, we review recent work on the molecular mechanisms by which 'epigenetic' information is transmitted between generations over different timescales, and the importance of this information for development and physiology.
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Affiliation(s)
- Marcos Francisco Perez
- Systems Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Ben Lehner
- Systems Biology Program, Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
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28
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Rojas-Ríos P, Simonelig M. piRNAs and PIWI proteins: regulators of gene expression in development and stem cells. Development 2018; 145:145/17/dev161786. [PMID: 30194260 DOI: 10.1242/dev.161786] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PIWI proteins and Piwi-interacting RNAs (piRNAs) have established and conserved roles in repressing transposable elements (TEs) in the germline of animals. However, in several biological contexts, a large proportion of piRNAs are not related to TE sequences and, accordingly, functions for piRNAs and PIWI proteins that are independent of TE regulation have been identified. This aspect of piRNA biology is expanding rapidly. Indeed, recent reports have revealed the role of piRNAs in the regulation of endogenous gene expression programs in germ cells, as well as in somatic tissues, challenging dogma in the piRNA field. In this Review, we focus on recent data addressing the biological and developmental functions of piRNAs, highlighting their roles in embryonic patterning, germ cell specification, stem cell biology, neuronal activity and metabolism.
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Affiliation(s)
- Patricia Rojas-Ríos
- mRNA Regulation and Development, IGH, Univ. Montpellier, CNRS, Montpellier 34396, France
| | - Martine Simonelig
- mRNA Regulation and Development, IGH, Univ. Montpellier, CNRS, Montpellier 34396, France
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29
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Abstract
piRNAs are known to silence transposable elements, but not all piRNAs match transposon sequences. Recent studies from Shen et al. (2018) and Zhang et al. (2018) identify rules for piRNA target recognition in Caenorhabditis elegans. Permissive pairing rules allow targeting of essentially all germline mRNAs, while protective mechanisms prevent silencing self-genes.
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Affiliation(s)
- Joshua M Svendsen
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Taiowa A Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.
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30
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Seth M, Shirayama M, Tang W, Shen EZ, Tu S, Lee HC, Weng Z, Mello CC. The Coding Regions of Germline mRNAs Confer Sensitivity to Argonaute Regulation in C. elegans. Cell Rep 2018; 22:2254-2264. [PMID: 29456100 PMCID: PMC5918280 DOI: 10.1016/j.celrep.2018.02.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/26/2018] [Accepted: 02/01/2018] [Indexed: 12/11/2022] Open
Abstract
Protein-coding genes undergo a wide array of regulatory interactions with factors that engage non-coding regions. Open reading frames (ORFs), in contrast, are thought to be constrained by coding function, precluding a major role in gene regulation. Here, we explore Piwi-interacting (pi)RNA-mediated transgene silencing in C. elegans and show that marked differences in the sensitivity to piRNA silencing map to the endogenous sequences within transgene ORFs. Artificially increasing piRNA targeting within the ORF of a resistant transgene can lead to a partial yet stable reduction in expression, revealing that piRNAs not only silence but can also “tune” gene expression. Our findings support a model that involves a temporal element to mRNA regulation by germline Argonautes, likely prior to translation, and suggest that piRNAs afford incremental control of germline mRNA expression by targeting the body of the mRNA, including the coding region.
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Affiliation(s)
- Meetu Seth
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA; Howard Hughes Medical Institute
| | - Masaki Shirayama
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA; Howard Hughes Medical Institute
| | - Wen Tang
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - En-Zhi Shen
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Shikui Tu
- Program in Bioinformatics and Integrative Biology, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Heng-Chi Lee
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA
| | - Craig C Mello
- RNA Therapeutics Institute, UMass Medical School, 368 Plantation Street, Worcester, MA 01605, USA; Howard Hughes Medical Institute.
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31
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Shen EZ, Chen H, Ozturk AR, Tu S, Shirayama M, Tang W, Ding YH, Dai SY, Weng Z, Mello CC. Identification of piRNA Binding Sites Reveals the Argonaute Regulatory Landscape of the C. elegans Germline. Cell 2018; 172:937-951.e18. [PMID: 29456082 DOI: 10.1016/j.cell.2018.02.002] [Citation(s) in RCA: 139] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 01/26/2018] [Accepted: 01/31/2018] [Indexed: 12/20/2022]
Abstract
piRNAs (Piwi-interacting small RNAs) engage Piwi Argonautes to silence transposons and promote fertility in animal germlines. Genetic and computational studies have suggested that C. elegans piRNAs tolerate mismatched pairing and in principle could target every transcript. Here we employ in vivo cross-linking to identify transcriptome-wide interactions between piRNAs and target RNAs. We show that piRNAs engage all germline mRNAs and that piRNA binding follows microRNA-like pairing rules. Targeting correlates better with binding energy than with piRNA abundance, suggesting that piRNA concentration does not limit targeting. In mRNAs silenced by piRNAs, secondary small RNAs accumulate at the center and ends of piRNA binding sites. In germline-expressed mRNAs, however, targeting by the CSR-1 Argonaute correlates with reduced piRNA binding density and suppression of piRNA-associated secondary small RNAs. Our findings reveal physiologically important and nuanced regulation of individual piRNA targets and provide evidence for a comprehensive post-transcriptional regulatory step in germline gene expression.
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Affiliation(s)
- En-Zhi Shen
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Hao Chen
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Bioinformatics Program, Boston University, Boston, MA 02215, USA
| | - Ahmet R Ozturk
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Shikui Tu
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Computer Science and Engineering, and CMaCH center, Shanghai Jiao Tong University, Shanghai, China
| | - Masaki Shirayama
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Howard Hughes Medical Institute
| | - Wen Tang
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Yue-He Ding
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Si-Yuan Dai
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Craig C Mello
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, USA; Howard Hughes Medical Institute.
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