1
|
Pamula MC, Lehmann R. How germ granules promote germ cell fate. Nat Rev Genet 2024:10.1038/s41576-024-00744-8. [PMID: 38890558 DOI: 10.1038/s41576-024-00744-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/08/2024] [Indexed: 06/20/2024]
Abstract
Germ cells are the only cells in the body capable of giving rise to a new organism, and this totipotency hinges on their ability to assemble membraneless germ granules. These specialized RNA and protein complexes are hallmarks of germ cells throughout their life cycle: as embryonic germ granules in late oocytes and zygotes, Balbiani bodies in immature oocytes, and nuage in maturing gametes. Decades of developmental, genetic and biochemical studies have identified protein and RNA constituents unique to germ granules and have implicated these in germ cell identity, genome integrity and gamete differentiation. Now, emerging research is defining germ granules as biomolecular condensates that achieve high molecular concentrations by phase separation, and it is assigning distinct roles to germ granules during different stages of germline development. This organization of the germ cell cytoplasm into cellular subcompartments seems to be critical not only for the flawless continuity through the germline life cycle within the developing organism but also for the success of the next generation.
Collapse
Affiliation(s)
| | - Ruth Lehmann
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
2
|
Ho S, Theurkauf W, Rice N. piRNA-Guided Transposon Silencing and Response to Stress in Drosophila Germline. Viruses 2024; 16:714. [PMID: 38793595 PMCID: PMC11125864 DOI: 10.3390/v16050714] [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] [Received: 03/28/2024] [Revised: 04/23/2024] [Accepted: 04/27/2024] [Indexed: 05/26/2024] Open
Abstract
Transposons are integral genome constituents that can be domesticated for host functions, but they also represent a significant threat to genome stability. Transposon silencing is especially critical in the germline, which is dedicated to transmitting inherited genetic material. The small Piwi-interacting RNAs (piRNAs) have a deeply conserved function in transposon silencing in the germline. piRNA biogenesis and function are particularly well understood in Drosophila melanogaster, but some fundamental mechanisms remain elusive and there is growing evidence that the pathway is regulated in response to genotoxic and environmental stress. Here, we review transposon regulation by piRNAs and the piRNA pathway regulation in response to stress, focusing on the Drosophila female germline.
Collapse
Affiliation(s)
- Samantha Ho
- Program in Molecular Medicine, University Campus, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA;
| | | | - Nicholas Rice
- Program in Molecular Medicine, University Campus, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA;
| |
Collapse
|
3
|
Yoth M, Maupetit-Méhouas S, Akkouche A, Gueguen N, Bertin B, Jensen S, Brasset E. Reactivation of a somatic errantivirus and germline invasion in Drosophila ovaries. Nat Commun 2023; 14:6096. [PMID: 37773253 PMCID: PMC10541861 DOI: 10.1038/s41467-023-41733-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 09/15/2023] [Indexed: 10/01/2023] Open
Abstract
Most Drosophila transposable elements are LTR retrotransposons, some of which belong to the genus Errantivirus and share structural and functional characteristics with vertebrate endogenous retroviruses. Like endogenous retroviruses, it is unclear whether errantiviruses retain some infectivity and transposition capacity. We created conditions where control of the Drosophila ZAM errantivirus through the piRNA pathway was abolished leading to its de novo reactivation in somatic gonadal cells. After reactivation, ZAM invaded the oocytes and severe fertility defects were observed. While ZAM expression persists in the somatic gonadal cells, the germline then set up its own adaptive genomic immune response by producing piRNAs against the constantly invading errantivirus, restricting invasion. Our results suggest that although errantiviruses are continuously repressed by the piRNA pathway, they may retain their ability to infect the germline and transpose, thus allowing them to efficiently invade the germline if they are expressed.
Collapse
Affiliation(s)
- Marianne Yoth
- iGReD, Université Clermont Auvergne, CNRS, INSERM, Faculté de Médecine, 63000, Clermont-Ferrand, France
| | | | - Abdou Akkouche
- iGReD, Université Clermont Auvergne, CNRS, INSERM, Faculté de Médecine, 63000, Clermont-Ferrand, France
| | - Nathalie Gueguen
- iGReD, Université Clermont Auvergne, CNRS, INSERM, Faculté de Médecine, 63000, Clermont-Ferrand, France
| | - Benjamin Bertin
- LIMAGRAIN EUROPE, Centre de recherche, 63720, Chappes, France
| | - Silke Jensen
- iGReD, Université Clermont Auvergne, CNRS, INSERM, Faculté de Médecine, 63000, Clermont-Ferrand, France.
| | - Emilie Brasset
- iGReD, Université Clermont Auvergne, CNRS, INSERM, Faculté de Médecine, 63000, Clermont-Ferrand, France.
| |
Collapse
|
4
|
Iyer SS, Sun Y, Seyfferth J, Manjunath V, Samata M, Alexiadis A, Kulkarni T, Gutierrez N, Georgiev P, Shvedunova M, Akhtar A. The NSL complex is required for piRNA production from telomeric clusters. Life Sci Alliance 2023; 6:e202302194. [PMID: 37399316 PMCID: PMC10313855 DOI: 10.26508/lsa.202302194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/15/2023] [Accepted: 06/20/2023] [Indexed: 07/05/2023] Open
Abstract
The NSL complex is a transcriptional activator. Germline-specific knockdown of NSL complex subunits NSL1, NSL2, and NSL3 results in reduced piRNA production from a subset of bidirectional piRNA clusters, accompanied by widespread transposon derepression. The piRNAs most transcriptionally affected by NSL2 and NSL1 RNAi map to telomeric piRNA clusters. At the chromatin level, these piRNA clusters also show decreased levels of H3K9me3, HP1a, and Rhino after NSL2 depletion. Using NSL2 ChIP-seq in ovaries, we found that this protein specifically binds promoters of telomeric transposons HeT-A, TAHRE, and TART Germline-specific depletion of NSL2 also led to a reduction in nuclear Piwi in nurse cells. Our findings thereby support a role for the NSL complex in promoting the transcription of piRNA precursors from telomeric piRNA clusters and in regulating Piwi levels in the Drosophila female germline.
Collapse
Affiliation(s)
- Shantanu S Iyer
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, Freiburg im Breisgau, Germany
- Faculty of Biology, University of Freiburg, Freiburg im Breisgau, Germany
| | - Yidan Sun
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Janine Seyfferth
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Vinitha Manjunath
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Maria Samata
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Anastasios Alexiadis
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Tanvi Kulkarni
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Noel Gutierrez
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Plamen Georgiev
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Maria Shvedunova
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| | - Asifa Akhtar
- Max Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany
| |
Collapse
|
5
|
Delanoue R, Clot C, Leray C, Pihl T, Hudry B. Y chromosome toxicity does not contribute to sex-specific differences in longevity. Nat Ecol Evol 2023; 7:1245-1256. [PMID: 37308701 PMCID: PMC10406604 DOI: 10.1038/s41559-023-02089-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 04/14/2023] [Indexed: 06/14/2023]
Abstract
While sex chromosomes carry sex-determining genes, they also often differ from autosomes in size and composition, consisting mainly of silenced heterochromatic repetitive DNA. Even though Y chromosomes show structural heteromorphism, the functional significance of such differences remains elusive. Correlative studies suggest that the amount of Y chromosome heterochromatin might be responsible for several male-specific traits, including sex-specific differences in longevity observed across a wide spectrum of species, including humans. However, experimental models to test this hypothesis have been lacking. Here we use the Drosophila melanogaster Y chromosome to investigate the relevance of sex chromosome heterochromatin in somatic organs in vivo. Using CRISPR-Cas9, we generated a library of Y chromosomes with variable levels of heterochromatin. We show that these different Y chromosomes can disrupt gene silencing in trans, on other chromosomes, by sequestering core components of the heterochromatin machinery. This effect is positively correlated to the level of Y heterochromatin. However, we also find that the ability of the Y chromosome to affect genome-wide heterochromatin does not generate physiological sex differences, including sexual dimorphism in longevity. Instead, we discovered that it is the phenotypic sex, female or male, that controls sex-specific differences in lifespan, rather than the presence of a Y chromosome. Altogether, our findings dismiss the 'toxic Y' hypothesis that postulates that the Y chromosome leads to reduced lifespan in XY individuals.
Collapse
Affiliation(s)
- Rénald Delanoue
- Institut de Biologie Valrose, Université Côte d'Azur, CNRS, INSERM, Nice, France.
| | - Charlène Clot
- Institut de Biologie Valrose, Université Côte d'Azur, CNRS, INSERM, Nice, France
| | - Chloé Leray
- Institut de Biologie Valrose, Université Côte d'Azur, CNRS, INSERM, Nice, France
| | - Thomas Pihl
- Institut de Biologie Valrose, Université Côte d'Azur, CNRS, INSERM, Nice, France
| | - Bruno Hudry
- Institut de Biologie Valrose, Université Côte d'Azur, CNRS, INSERM, Nice, France.
| |
Collapse
|
6
|
Curnutte HA, Lan X, Sargen M, Ao Ieong SM, Campbell D, Kim H, Liao Y, Lazar SB, Trcek T. Proteins rather than mRNAs regulate nucleation and persistence of Oskar germ granules in Drosophila. Cell Rep 2023; 42:112723. [PMID: 37384531 PMCID: PMC10439980 DOI: 10.1016/j.celrep.2023.112723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 04/24/2023] [Accepted: 06/13/2023] [Indexed: 07/01/2023] Open
Abstract
RNA granules are membraneless condensates that provide functional compartmentalization within cells. The mechanisms by which RNA granules form are under intense investigation. Here, we characterize the role of mRNAs and proteins in the formation of germ granules in Drosophila. Super-resolution microscopy reveals that the number, size, and distribution of germ granules is precisely controlled. Surprisingly, germ granule mRNAs are not required for the nucleation or the persistence of germ granules but instead control their size and composition. Using an RNAi screen, we determine that RNA regulators, helicases, and mitochondrial proteins regulate germ granule number and size, while the proteins of the endoplasmic reticulum, nuclear pore complex, and cytoskeleton control their distribution. Therefore, the protein-driven formation of Drosophila germ granules is mechanistically distinct from the RNA-dependent condensation observed for other RNA granules such as stress granules and P-bodies.
Collapse
Affiliation(s)
- Harrison A Curnutte
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Xinyue Lan
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Manuel Sargen
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Si Man Ao Ieong
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Dylan Campbell
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Hyosik Kim
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Yijun Liao
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Sarah Bailah Lazar
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Tatjana Trcek
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA.
| |
Collapse
|
7
|
Adashev VE, Kotov AA, Olenina LV. RNA Helicase Vasa as a Multifunctional Conservative Regulator of Gametogenesis in Eukaryotes. Curr Issues Mol Biol 2023; 45:5677-5705. [PMID: 37504274 PMCID: PMC10378496 DOI: 10.3390/cimb45070358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 06/30/2023] [Accepted: 07/03/2023] [Indexed: 07/29/2023] Open
Abstract
Being a conservative marker of germ cells across metazoan species, DEAD box RNA helicase Vasa (DDX4) remains the subject of worldwide investigations thanks to its multiple functional manifestations. Vasa takes part in the preformation of primordial germ cells in a group of organisms and contributes to the maintenance of germline stem cells. Vasa is an essential player in the piRNA-mediated silencing of harmful genomic elements and in the translational regulation of selected mRNAs. Vasa is the top hierarchical protein of germ granules, liquid droplet organelles that compartmentalize RNA processing factors. Here, we survey current advances and problems in the understanding of the multifaceted functions of Vasa proteins in the gametogenesis of different eukaryotic organisms, from nematodes to humans.
Collapse
Affiliation(s)
- Vladimir E Adashev
- Department of Molecular Mechanisms for Realization of Genetic Information, Laboratory of Biochemical Genetics of Animals, National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia
| | - Alexei A Kotov
- Department of Molecular Mechanisms for Realization of Genetic Information, Laboratory of Biochemical Genetics of Animals, National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia
| | - Ludmila V Olenina
- Department of Molecular Mechanisms for Realization of Genetic Information, Laboratory of Biochemical Genetics of Animals, National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia
| |
Collapse
|
8
|
Kulkarni A, Ewen-Campen B, Terao K, Matsumoto Y, Li Y, Watanabe T, Kao JA, Parhad SS, Ylla G, Mizunami M, Extavour CG. oskar acts with the transcription factor Creb to regulate long-term memory in crickets. Proc Natl Acad Sci U S A 2023; 120:e2218506120. [PMID: 37192168 PMCID: PMC10214185 DOI: 10.1073/pnas.2218506120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 03/28/2023] [Indexed: 05/18/2023] Open
Abstract
Novel genes have the potential to drive the evolution of new biological mechanisms, or to integrate into preexisting regulatory circuits and contribute to the regulation of older, conserved biological functions. One such gene, the novel insect-specific gene oskar, was first identified based on its role in establishing the Drosophila melanogaster germ line. We previously showed that this gene likely arose through an unusual domain transfer event involving bacterial endosymbionts and played a somatic role before evolving its well-known germ line function. Here, we provide empirical support for this hypothesis in the form of evidence for a neural role for oskar. We show that oskar is expressed in the adult neural stem cells of a hemimetabolous insect, the cricket Gryllus bimaculatus. In these stem cells, called neuroblasts, oskar is required together with the ancient animal transcription factor Creb to regulate long-term (but not short-term) olfactory memory. We provide evidence that oskar positively regulates Creb, which plays a conserved role in long-term memory across animals, and that oskar in turn may be a direct target of Creb. Together with previous reports of a role for oskar in nervous system development and function in crickets and flies, our results are consistent with the hypothesis that oskar's original somatic role may have been in the insect nervous system. Moreover, its colocalization and functional cooperation with the conserved pluripotency gene piwi in the nervous system may have facilitated oskar's later co-option to the germ line in holometabolous insects.
Collapse
Affiliation(s)
- Arpita Kulkarni
- Department of Organismic and Evolutionary Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
| | - Ben Ewen-Campen
- Department of Organismic and Evolutionary Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
| | - Kanta Terao
- Graduate School of Life Science, Hokkaido University, Sapporo060-0810, Japan
| | | | - Yaolong Li
- Graduate School of Life Science, Hokkaido University, Sapporo060-0810, Japan
| | - Takayuki Watanabe
- Faculty of Science, Hokkaido University, Sapporo060-0810, Japan
- Research Center for Integrative Evolutionary Science, School of Advanced Sciences, Sokendai-Hayama, Kanagawa240-0193, Japan
| | - Jonchee A. Kao
- Department of Molecular and Cellular Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
| | - Swapnil S. Parhad
- University of Massachusetts Chan Medical School, Program in Molecular Medicine, Worcester, MA01655
| | - Guillem Ylla
- Department of Organismic and Evolutionary Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
| | - Makoto Mizunami
- Faculty of Science, Hokkaido University, Sapporo060-0810, Japan
| | - Cassandra G. Extavour
- Department of Organismic and Evolutionary Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
- Department of Molecular and Cellular Biology, Faculty of Arts and Sciences, Harvard University, Cambridge, MA02138
- HHMI, Chevy Chase, MD20815
| |
Collapse
|
9
|
Copley KE, Shorter J. Repetitive elements in aging and neurodegeneration. Trends Genet 2023; 39:381-400. [PMID: 36935218 PMCID: PMC10121923 DOI: 10.1016/j.tig.2023.02.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 03/19/2023]
Abstract
Repetitive elements (REs), such as transposable elements (TEs) and satellites, comprise much of the genome. Here, we review how TEs and (peri)centromeric satellite DNA may contribute to aging and neurodegenerative disorders, including amyotrophic lateral sclerosis (ALS). Alterations in RE expression, retrotransposition, and chromatin microenvironment may shorten lifespan, elicit neurodegeneration, and impair memory and movement. REs may cause these phenotypes via DNA damage, protein sequestration, insertional mutagenesis, and inflammation. We discuss several TE families, including gypsy, HERV-K, and HERV-W, and how TEs interact with various factors, including transactive response (TAR) DNA-binding protein 43 kDa (TDP-43) and the siRNA and piwi-interacting (pi)RNA systems. Studies of TEs in neurodegeneration have focused on Drosophila and, thus, further examination in mammals is needed. We suggest that therapeutic silencing of REs could help mitigate neurodegenerative disorders.
Collapse
Affiliation(s)
- Katie E Copley
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; Neuroscience Graduate Group, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.
| |
Collapse
|
10
|
Santos D, Feng M, Kolliopoulou A, Taning CNT, Sun J, Swevers L. What Are the Functional Roles of Piwi Proteins and piRNAs in Insects? INSECTS 2023; 14:insects14020187. [PMID: 36835756 PMCID: PMC9962485 DOI: 10.3390/insects14020187] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/09/2023] [Accepted: 02/11/2023] [Indexed: 06/01/2023]
Abstract
Research on Piwi proteins and piRNAs in insects has focused on three experimental models: oogenesis and spermatogenesis in Drosophila melanogaster, the antiviral response in Aedes mosquitoes and the molecular analysis of primary and secondary piRNA biogenesis in Bombyx mori-derived BmN4 cells. Significant unique and complementary information has been acquired and has led to a greater appreciation of the complexity of piRNA biogenesis and Piwi protein function. Studies performed in other insect species are emerging and promise to add to the current state of the art on the roles of piRNAs and Piwi proteins. Although the primary role of the piRNA pathway is genome defense against transposons, particularly in the germline, recent findings also indicate an expansion of its functions. In this review, an extensive overview is presented of the knowledge of the piRNA pathway that so far has accumulated in insects. Following a presentation of the three major models, data from other insects were also discussed. Finally, the mechanisms for the expansion of the function of the piRNA pathway from transposon control to gene regulation were considered.
Collapse
Affiliation(s)
- Dulce Santos
- Research Group of Molecular Developmental Physiology and Signal Transduction, Division of Animal Physiology and Neurobiology, Department of Biology, KU Leuven, Naamsestraat 59, 3000 Leuven, Belgium
| | - Min Feng
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Anna Kolliopoulou
- Insect Molecular Genetics and Biotechnology, Institute of Biosciences & Applications, National Centre for Scientific Research “Demokritos”, Aghia Paraskevi, 15341 Athens, Greece
| | - Clauvis N. T. Taning
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
| | - Jingchen Sun
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou 510642, China
| | - Luc Swevers
- Insect Molecular Genetics and Biotechnology, Institute of Biosciences & Applications, National Centre for Scientific Research “Demokritos”, Aghia Paraskevi, 15341 Athens, Greece
| |
Collapse
|
11
|
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.
Collapse
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.
| |
Collapse
|
12
|
Sohn EJ, Oh SO. P-Element-Induced Wimpy Testis Proteins and P-Element-Induced Wimpy Testis-Interacting RNAs Expression in Ovarian Cancer Stem Cells. Genet Test Mol Biomarkers 2023; 27:56-64. [PMID: 36853842 DOI: 10.1089/gtmb.2022.0113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023] Open
Abstract
Background: P-element-induced wimpy testis (PIWI)-interacting RNAs (piRNAs) are a type of noncoding RNA and are predominantly expressed in germline cells. piRNAs function as gene regulators and potential biomarkers for the development of a number of malignancies. The biological importance of piRNAs in ovarian cancer is still unknown. In this study, we investigated the expression of piRNAs in ovarian cancer stem cells and compared it with that in adherent cells. Methods: To assess changes in the expression levels of PIWIL1/HIWI, PIWIL2/HILI, PIWIL3, and PIWIL4/HIWI2, we used quantitative reverse-transcription polymerase chain reaction (RT-qPCR) analysis. Changes in piRNA expression levels in ovarian cancer stem cells were analyzed using Arraystar piRNA microarray screening. Gene Ontology (GO) enrichment analysis was conducted to determine the potential functions of piRNAs. Results: Using microarray analysis, we identified a cohort of differentially expressed piRNAs. Fifteen piRNAs, including DQ570763 and DQ597396, were downregulated, and 58 piRNAs were upregulated when compared with those in adherent A2780 and SKOV3 cells (p > 0.05, >2.0, respectively). GO functions of the downregulated piRNAs (DQ570763 and DQ570797) suggest that their roles are commonly associated with the Golgi apparatus. In addition, A2780-SP and SKOV3-SP cells had higher PIWIL3 and PIWIL4 mRNA levels than adherent cells (A2780 and SKOV3). Moreover, we determined, using receiver operating characteristic plot, that the expression level of PIWIL4 was lower in responders than in nonresponders after treatment with platins in patients with ovarian cancer. Finally, in ovarian cancer, PIWIL4 expression was associated with somatic mutations of dynein axonemal heavy chain 2, signal induced proliferation associated 1 like 2, YTH N6-methyladenosine RNA-binding protein 1, TBC1 domain family member 8, and LPS responsive Beige-like anchor protein. Conclusion: Our study showed that PIWI proteins and piRNAs are potential diagnostic and prognostic biomarkers for ovarian cancer.
Collapse
Affiliation(s)
- Eun Jung Sohn
- College of Medicine, Pusan National University, Yangsan, Korea
| | - Sae-Ock Oh
- Department of Anatomy, School of Medicine, Pusan National University, Yangsan, Korea
| |
Collapse
|
13
|
Nieken KJ, O’Brien K, McDonnell A, Zhaunova L, Ohkura H. A large-scale RNAi screen reveals that mitochondrial function is important for meiotic chromosome organization in oocytes. Chromosoma 2023; 132:1-18. [PMID: 36648541 PMCID: PMC9981535 DOI: 10.1007/s00412-023-00784-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/22/2022] [Accepted: 01/03/2023] [Indexed: 01/18/2023]
Abstract
In prophase of the first meiotic division, chromatin forms a compact spherical cluster called the karyosome within the enlarged oocyte nucleus in Drosophila melanogaster. Similar clustering of chromatin has been widely observed in oocytes in many species including humans. It was previously shown that the proper karyosome formation is required for faithful chromosome segregation, but knowledge about its formation and maintenance is limited. To identify genes involved in karyosome formation, we carried out a large-scale cytological screen using Drosophila melanogaster oocytes. This screen comprised 3916 genes expressed in ovaries, of which 106 genes triggered reproducible karyosome defects upon knockdown. The karyosome defects in 24 out of these 106 genes resulted from activation of the meiotic recombination checkpoint, suggesting possible roles in DNA repair or piRNA processing. The other genes identified in this screen include genes with functions linked to chromatin, nuclear envelope, and actin. We also found that silencing of genes with mitochondrial functions, including electron transport chain components, induced a distinct karyosome defect typically with de-clustered chromosomes located close to the nuclear envelope. Furthermore, mitochondrial dysfunction not only impairs karyosome formation and maintenance, but also delays synaptonemal complex disassembly in cells not destined to become the oocyte. These karyosome defects do not appear to be mediated by apoptosis. This large-scale unbiased study uncovered a set of genes required for karyosome formation and revealed a new link between mitochondrial dysfunction and chromatin organization in oocytes.
Collapse
Affiliation(s)
- Karen Jule Nieken
- grid.4305.20000 0004 1936 7988Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF UK
| | - Kathryn O’Brien
- grid.4305.20000 0004 1936 7988Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF UK
| | - Alexander McDonnell
- grid.4305.20000 0004 1936 7988Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF UK
| | - Liudmila Zhaunova
- grid.4305.20000 0004 1936 7988Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF UK
| | - Hiroyuki Ohkura
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK.
| |
Collapse
|
14
|
Abstract
By the time a Drosophila egg is laid, both major body axes have already been defined and it contains all the nutrients needed to develop into a free-living larva in 24 h. By contrast, it takes almost a week to make an egg from a female germline stem cell, during the complex process of oogenesis. This review will discuss key symmetry-breaking steps in Drosophila oogenesis that lead to the polarisation of both body axes: the asymmetric divisions of the germline stem cells; the selection of the oocyte from the 16-cell germline cyst; the positioning of the oocyte at the posterior of the cyst; Gurken signalling from the oocyte to polarise the anterior-posterior axis of the somatic follicle cell epithelium around the developing germline cyst; the signalling back from the posterior follicle cells to polarise the anterior-posterior axis of the oocyte; and the migration of the oocyte nucleus that specifies the dorsal-ventral axis. Since each event creates the preconditions for the next, I will focus on the mechanisms that drive these symmetry-breaking steps, how they are linked and the outstanding questions that remain to be answered.
Collapse
|
15
|
Yamamoto‐Matsuda H, Miyoshi K, Moritoh M, Yoshitane H, Fukada Y, Saito K, Yamanaka S, Siomi MC. Lint‐O
cooperates with L(3)mbt in target gene suppression to maintain homeostasis in fly ovary and brain. EMBO Rep 2022; 23:e53813. [PMID: 35993198 PMCID: PMC9535798 DOI: 10.15252/embr.202153813] [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: 08/16/2021] [Revised: 08/08/2022] [Accepted: 08/09/2022] [Indexed: 11/23/2022] Open
Abstract
Loss‐of‐function mutations in Drosophila lethal(3)malignant brain tumor [l(3)mbt] cause ectopic expression of germline genes and brain tumors. Loss of L(3)mbt function in ovarian somatic cells (OSCs) aberrantly activates germ‐specific piRNA amplification and leads to infertility. However, the underlying mechanism remains unclear. Here, ChIP‐seq for L(3)mbt in cultured OSCs and RNA‐seq before and after L(3)mbt depletion shows that L(3)mbt genomic binding is not necessarily linked to gene regulation and that L(3)mbt controls piRNA pathway genes in multiple ways. Lack of known L(3)mbt co‐repressors, such as Lint‐1, has little effect on the levels of piRNA amplifiers. Identification of L(3)mbt interactors in OSCs and subsequent analysis reveals CG2662 as a novel co‐regulator of L(3)mbt, termed “L(3)mbt interactor in OSCs” (Lint‐O). Most of the L(3)mbt‐bound piRNA amplifier genes are also bound by Lint‐O in a similar fashion. Loss of Lint‐O impacts the levels of piRNA amplifiers, similar to the lack of L(3)mbt. The lint‐O‐deficient flies exhibit female sterility and tumorous brains. Thus, L(3)mbt and its novel co‐suppressor Lint‐O cooperate in suppressing target genes to maintain homeostasis in the ovary and brain.
Collapse
Affiliation(s)
- Hitomi Yamamoto‐Matsuda
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| | - Keita Miyoshi
- Department of Chromosome Science National Institute of Genetics, Research Organization of Information and Systems Shizuoka Japan
- Department of Genetics School of Life Science, SOKENDAI Shizuoka Japan
| | - Mai Moritoh
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| | - Hikari Yoshitane
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| | - Yoshitaka Fukada
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| | - Kuniaki Saito
- Department of Chromosome Science National Institute of Genetics, Research Organization of Information and Systems Shizuoka Japan
- Department of Genetics School of Life Science, SOKENDAI Shizuoka Japan
| | - Soichiro Yamanaka
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| | - Mikiko C Siomi
- Department of Biological Sciences, Graduate School of Science The University of Tokyo Tokyo Japan
| |
Collapse
|
16
|
Yushkova E. Radiobiological features in offspring of natural populations of Drosophila melanogaster after Chernobyl accident. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2022; 63:84-97. [PMID: 35275441 DOI: 10.1002/em.22476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/24/2022] [Accepted: 03/08/2022] [Indexed: 06/14/2023]
Abstract
In their natural habitats, populations of organisms are faced with different levels of chronic low-intensity radiation, causing a wide range of radiobiological effects (from radiosensitivity to radioadaptive response and hormesis). In this study, specimens of Drosophila melanogaster were selected from territories of the Chernobyl nuclear power plant with different levels of radioactive contamination. The isogenic stocks derived from these specimens represent the genetic systems of current populations and make it possible to study radioresistance and its mechanisms in future generations under controlled laboratory conditions. Previous studies have shown that transgenerational radiation effects at the level of lethal mutations and survival rate are unstable and depend not only on the level of chronic low-intensity irradiation, but also on other factors. A single acute irradiation exposure of offspring whose parents inhabited a site with a higher level of chronic irradiation made it possible to reveal pronounced radioresistant features in the offspring. And the offspring whose parents were exposed to radiation levels close to the natural radiation background, on the contrary, acquired radiosensitive features. Their response to acute exposure includes a high-frequency of lethal mutations and a short lifespan. The differential response to different levels of chronic parental exposure is caused by differences in the activities of certain transposons that destabilize the genome. Our data contribute to the understanding of genetic and epigenetic mechanisms (via transposon activity) of the effect of parental radiation exposure on the health and adaptive potential of populations affected by the technogenically increased radiation background.
Collapse
Affiliation(s)
- Elena Yushkova
- Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Science, Syktyvkar, Russia
| |
Collapse
|
17
|
Suda K, Hayashi SR, Tamura K, Takamatsu N, Ito M. Activation of DNA Transposons and Evolution of piRNA Genes Through Interspecific Hybridization in Xenopus Frogs. Front Genet 2022; 13:766424. [PMID: 35173768 PMCID: PMC8841583 DOI: 10.3389/fgene.2022.766424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 01/13/2022] [Indexed: 01/28/2023] Open
Abstract
Interspecific hybridization between two closely related species sometimes resulted in a new species with allotetraploid genomes. Many clawed frog species belonging to the Xenopus genus have diverged from the allotetraploid ancestor created by the hybridization of two closely related species with the predicted L and S genomes. There are species-specific repeated sequences including transposable elements in each genome of organisms that reproduce sexually. To understand what happened on and after the hybridization of the two distinct systems consisting of repeated sequences and their corresponding piRNAs, we isolated small RNAs from ovaries and testes of three Xenopus species consisting of allotetraploid X. laevis and X. borealis and diploid X. tropicalis as controls. After a comprehensive sequencing and selection of piRNAs, comparison of their sequences showed that most piRNA sequences were different between the ovaries and testes in all three species. We compared piRNA and genome sequences and specified gene clusters for piRNA expression in each genome. The synteny and homology analyses showed many distinct piRNA clusters among the three species and even between the two L and/or S subgenomes, indicating that most clusters of the two allotetraploid species changed after hybridization. Moreover, evolutionary analysis showed that DNA transposons including Kolobok superfamily might get activated just after hybridization and then gradually inactivated. These findings suggest that some DNA transposons and their piRNAs might greatly influence allotetraploid genome evolution after hybridization.
Collapse
Affiliation(s)
| | | | | | | | - Michihiko Ito
- Department of Bioscience, School of Science, Kitasato University, Sagamihara, Japan
| |
Collapse
|
18
|
Williams AE, Shrivastava G, Gittis AG, Ganesan S, Martin-Martin I, Valenzuela Leon PC, Olson KE, Calvo E. Aedes aegypti Piwi4 Structural Features Are Necessary for RNA Binding and Nuclear Localization. Int J Mol Sci 2021; 22:ijms222312733. [PMID: 34884537 PMCID: PMC8657434 DOI: 10.3390/ijms222312733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/21/2022] Open
Abstract
The PIWI-interacting RNA (piRNA) pathway provides an RNA interference (RNAi) mechanism known from Drosophila studies to maintain the integrity of the germline genome by silencing transposable elements (TE). Aedes aegypti mosquitoes, which are the key vectors of several arthropod-borne viruses, exhibit an expanded repertoire of Piwi proteins involved in the piRNA pathway, suggesting functional divergence. Here, we investigate RNA-binding dynamics and subcellular localization of A. aegypti Piwi4 (AePiwi4), a Piwi protein involved in antiviral immunity and embryonic development, to better understand its function. We found that AePiwi4 PAZ (Piwi/Argonaute/Zwille), the domain that binds the 3′ ends of piRNAs, bound to mature (3′ 2′ O-methylated) and unmethylated RNAs with similar micromolar affinities (KD = 1.7 ± 0.8 μM and KD of 5.0 ± 2.2 μM, respectively; p = 0.05) in a sequence independent manner. Through site-directed mutagenesis studies, we identified highly conserved residues involved in RNA binding and found that subtle changes in the amino acids flanking the binding pocket across PAZ proteins have significant impacts on binding behaviors, likely by impacting the protein secondary structure. We also analyzed AePiwi4 subcellular localization in mosquito tissues. We found that the protein is both cytoplasmic and nuclear, and we identified an AePiwi4 nuclear localization signal (NLS) in the N-terminal region of the protein. Taken together, these studies provide insights on the dynamic role of AePiwi4 in RNAi and pave the way for future studies aimed at understanding Piwi interactions with diverse RNA populations.
Collapse
Affiliation(s)
- Adeline E. Williams
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523, USA
| | - Gaurav Shrivastava
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
| | - Apostolos G. Gittis
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
| | - Sundar Ganesan
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
| | - Ines Martin-Martin
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
| | - Paola Carolina Valenzuela Leon
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
| | - Ken E. Olson
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523, USA
- Correspondence: (K.E.O.); (E.C.)
| | - Eric Calvo
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA; (A.E.W.); (G.S.); (A.G.G.); (S.G.); (I.M.-M.); (P.C.V.L.)
- Correspondence: (K.E.O.); (E.C.)
| |
Collapse
|
19
|
ElMaghraby MF, Tirian L, Senti KA, Meixner K, Brennecke J. A genetic toolkit for studying transposon control in the Drosophila melanogaster ovary. Genetics 2021; 220:6414620. [PMID: 34718559 PMCID: PMC8733420 DOI: 10.1093/genetics/iyab179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Accepted: 09/19/2021] [Indexed: 11/12/2022] Open
Abstract
Argonaute proteins of the PIWI clade complexed with PIWI-interacting RNAs (piRNAs) protect the animal germline genome by silencing transposable elements. One of the leading experimental systems for studying piRNA biology is the Drosophila melanogaster ovary. In addition to classical mutagenesis, transgenic RNA interference (RNAi), which enables tissue-specific silencing of gene expression, plays a central role in piRNA research. Here, we establish a versatile toolkit focused on piRNA biology that combines germline transgenic RNAi, GFP marker lines for key proteins of the piRNA pathway, and reporter transgenes to establish genetic hierarchies. We compare constitutive, pan-germline RNAi with an equally potent transgenic RNAi system that is activated only after germ cell cyst formation. Stage-specific RNAi allows us to investigate the role of genes essential for germline cell survival, for example nuclear RNA export or the SUMOylation pathway, in piRNA-dependent and independent transposon silencing. Our work forms the basis for an expandable genetic toolkit provided by the Vienna Drosophila Resource Center.
Collapse
Affiliation(s)
- Mostafa F ElMaghraby
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria.,Vienna BioCenter PhD Program, Doctoral School at the University of Vienna and Medical University of Vienna, 1030 Vienna, Austria
| | - Laszlo Tirian
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Kirsten-André Senti
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Katharina Meixner
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Julius Brennecke
- Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| |
Collapse
|
20
|
Loss of telomere silencing is accompanied by dysfunction of Polo kinase and centrosomes during Drosophila oogenesis and early development. PLoS One 2021; 16:e0258156. [PMID: 34624021 PMCID: PMC8500440 DOI: 10.1371/journal.pone.0258156] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 09/18/2021] [Indexed: 12/03/2022] Open
Abstract
Telomeres are nucleoprotein complexes that protect the ends of eukaryotic linear chromosomes from degradation and fusions. Telomere dysfunction leads to cell growth arrest, oncogenesis, and premature aging. Telomeric RNAs have been found in all studied species; however, their functions and biogenesis are not clearly understood. We studied the mechanisms of development disorders observed upon overexpression of telomeric repeats in Drosophila. In somatic cells, overexpression of telomeric retrotransposon HeT-A is cytotoxic and leads to the accumulation of HeT-A Gag near centrosomes. We found that RNA and RNA-binding protein Gag encoded by the telomeric retrotransposon HeT-A interact with Polo and Cdk1 mitotic kinases, which are conserved regulators of centrosome biogenesis and cell cycle. The depletion of proteins Spindle E, Ccr4 or Ars2 resulting in HeT-A overexpression in the germline was accompanied by mislocalization of Polo as well as its abnormal stabilization during oogenesis and severe deregulation of centrosome biogenesis leading to maternal-effect embryonic lethality. These data suggest a mechanistic link between telomeric HeT-A ribonucleoproteins and cell cycle regulators that ensures the cell response to telomere dysfunction.
Collapse
|
21
|
Gebert D, Neubert LK, Lloyd C, Gui J, Lehmann R, Teixeira FK. Large Drosophila germline piRNA clusters are evolutionarily labile and dispensable for transposon regulation. Mol Cell 2021; 81:3965-3978.e5. [PMID: 34352205 PMCID: PMC8516431 DOI: 10.1016/j.molcel.2021.07.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/23/2021] [Accepted: 07/10/2021] [Indexed: 12/13/2022]
Abstract
PIWI proteins and their guiding Piwi-interacting small RNAs (piRNAs) are crucial for fertility and transposon defense in the animal germline. In most species, the majority of piRNAs are produced from distinct large genomic loci, called piRNA clusters. It is assumed that germline-expressed piRNA clusters, particularly in Drosophila, act as principal regulators to control transposons dispersed across the genome. Here, using synteny analysis, we show that large clusters are evolutionarily labile, arise at loci characterized by recurrent chromosomal rearrangements, and are mostly species-specific across the Drosophila genus. By engineering chromosomal deletions in D. melanogaster, we demonstrate that the three largest germline clusters, which account for the accumulation of >40% of all transposon-targeting piRNAs in ovaries, are neither required for fertility nor for transposon regulation in trans. We provide further evidence that dispersed elements, rather than the regulatory action of large Drosophila germline clusters in trans, may be central for transposon defense.
Collapse
Affiliation(s)
- Daniel Gebert
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Lena K Neubert
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Catrin Lloyd
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Jinghua Gui
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Ruth Lehmann
- Howard Hughes Medical Institute (HHMI) and Kimmel Center for Biology and Medicine of the Skirball Institute, Department of Cell Biology, New York University School of Medicine, New York, NY 10016, USA.
| | | |
Collapse
|
22
|
Li D, Taylor DH, van Wolfswinkel JC. PIWI-mediated control of tissue-specific transposons is essential for somatic cell differentiation. Cell Rep 2021; 37:109776. [PMID: 34610311 PMCID: PMC8532177 DOI: 10.1016/j.celrep.2021.109776] [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: 07/07/2020] [Revised: 07/27/2021] [Accepted: 09/07/2021] [Indexed: 12/24/2022] Open
Abstract
PIWI proteins are known as mediators of transposon silencing in animal germlines but are also found in adult pluripotent stem cells of highly regenerative animals, where they are essential for regeneration. Study of the nuclear PIWI protein SMEDWI-2 in the planarian somatic stem cell system reveals an intricate interplay between transposons and cell differentiation in which a subset of transposons is inevitably activated during cell differentiation, and the PIWI protein is required to regain control. Absence of SMEDWI-2 leads to tissue-specific transposon derepression related to cell-type-specific chromatin remodeling events and in addition causes reduced accessibility of lineage-specific genes and defective cell differentiation, resulting in fatal tissue dysfunction. Finally, we show that additional PIWI proteins provide a stem-cell-specific second layer of protection in planarian neoblasts. These findings reveal a far-reaching role of PIWI proteins and PIWI-interacting RNAs (piRNAs) in stem cell biology and cell differentiation.
Collapse
Affiliation(s)
- Danyan Li
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - David H Taylor
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - Josien C van Wolfswinkel
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT 06511, USA.
| |
Collapse
|
23
|
Chen P, Luo Y, Aravin AA. RDC complex executes a dynamic piRNA program during Drosophila spermatogenesis to safeguard male fertility. PLoS Genet 2021; 17:e1009591. [PMID: 34473737 PMCID: PMC8412364 DOI: 10.1371/journal.pgen.1009591] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 05/10/2021] [Indexed: 11/19/2022] Open
Abstract
piRNAs are small non-coding RNAs that guide the silencing of transposons and other targets in animal gonads. In Drosophila female germline, many piRNA source loci dubbed “piRNA clusters” lack hallmarks of active genes and exploit an alternative path for transcription, which relies on the Rhino-Deadlock-Cutoff (RDC) complex. RDC was thought to be absent in testis, so it remains to date unknown how piRNA cluster transcription is regulated in the male germline. We found that components of RDC complex are expressed in male germ cells during early spermatogenesis, from germline stem cells (GSCs) to early spermatocytes. RDC is essential for expression of dual-strand piRNA clusters and transposon silencing in testis; however, it is dispensable for expression of Y-linked Suppressor of Stellate piRNAs and therefore Stellate silencing. Despite intact Stellate repression, males lacking RDC exhibited compromised fertility accompanied by germline DNA damage and GSC loss. Thus, piRNA-guided repression is essential for normal spermatogenesis beyond Stellate silencing. While RDC associates with multiple piRNA clusters in GSCs and early spermatogonia, its localization changes in later stages as RDC concentrates on a single X-linked locus, AT-chX. Dynamic RDC localization is paralleled by changes in piRNA cluster expression, indicating that RDC executes a fluid piRNA program during different stages of spermatogenesis. These results disprove the common belief that RDC is dispensable for piRNA biogenesis in testis and uncover the unexpected, sexually dimorphic and dynamic behavior of a core piRNA pathway machinery. Large fractions of eukaryotic genomes are occupied by mobile genetic elements called transposons. Active transposons can move in the genome causing DNA damage and mutations, while inactive copies can contribute to chromosome organization and regulation of gene expression. Host cells employ several mechanisms to discriminate transposons from other genes and repress transposon activities. In germ cells, a conserved class of short RNAs called Piwi-interacting (pi)RNAs recognize target RNAs in both the nucleus and cytoplasm and then guide transposon repression by preventing their transcription and destroying their RNAs. piRNAs are encoded in extended genomic regions dubbed piRNA clusters. Previously, composition and regulation of piRNA clusters were studied in the female germline of fruit flies, where a nuclear protein complex, the RDC complex, was shown to promote non-canonical transcription of these regions. However, RDC was believed to be dispensable in males. Here, we showed that RDC is essential for transposon repression in males, and males lacking RDC exhibit compromised fertility and loss of germ cells. We found that RDC binds multiple piRNA clusters in early germ cells but concentrates on a single locus at later stages. Our results indicate dynamic regulation of loci that produce piRNAs and, therefore, piRNA targets throughout spermatogenesis.
Collapse
Affiliation(s)
- Peiwei Chen
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California, United States of America
- * E-mail: (PC); (AAA)
| | - Yicheng Luo
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California, United States of America
| | - Alexei A. Aravin
- California Institute of Technology, Division of Biology and Biological Engineering, Pasadena, California, United States of America
- * E-mail: (PC); (AAA)
| |
Collapse
|
24
|
Onishi R, Yamanaka S, Siomi MC. piRNA- and siRNA-mediated transcriptional repression in Drosophila, mice, and yeast: new insights and biodiversity. EMBO Rep 2021; 22:e53062. [PMID: 34347367 PMCID: PMC8490990 DOI: 10.15252/embr.202153062] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/10/2021] [Accepted: 07/19/2021] [Indexed: 12/26/2022] Open
Abstract
The PIWI‐interacting RNA (piRNA) pathway acts as a self‐defense mechanism against transposons to maintain germline genome integrity. Failures in the piRNA pathway cause DNA damage in the germline genome, disturbing inheritance of “correct” genetic information by the next generations and leading to infertility. piRNAs execute transposon repression in two ways: degrading their RNA transcripts and compacting the genomic loci via heterochromatinization. The former event is mechanistically similar to siRNA‐mediated RNA cleavage that occurs in the cytoplasm and has been investigated in many species including nematodes, fruit flies, and mammals. The latter event seems to be mechanistically parallel to siRNA‐centered kinetochore assembly and subsequent chromosome segregation, which has so far been studied particularly in fission yeast. Despite the interspecies conservations, the overall schemes of the nuclear events show clear biodiversity across species. In this review, we summarize the recent progress regarding piRNA‐mediated transcriptional silencing in Drosophila and discuss the biodiversity by comparing it with the equivalent piRNA‐mediated system in mice and the siRNA‐mediated system in fission yeast.
Collapse
Affiliation(s)
- Ryo Onishi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Soichiro Yamanaka
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Mikiko C Siomi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| |
Collapse
|
25
|
Jia Z, Wang Y, Sun X, Zhao X, Zhang Y, Xu S, Wang Y, Li Y. Effect of lncRNA XLOC_005950 knockout by CRISPR/Cas9 gene editing on energy metabolism and proliferation in osteosarcoma MG63 cells mediated by hsa-miR-542-3p. Oncol Lett 2021; 22:669. [PMID: 34386091 PMCID: PMC8298990 DOI: 10.3892/ol.2021.12930] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 05/06/2021] [Indexed: 12/11/2022] Open
Abstract
Cancer cells use glucose via glycolysis to maintain tumor cell proliferation. However, the effect of long non-coding RNAs (lncRNAs) on glycolysis in osteosarcoma (OS) cells remains unclear. The present study aimed to investigate the involvement of the lncRNA XLOC_005950/hsa-microRNA (miR)-542-3p/phosphofructokinase, muscle (PFKM) axis in the regulation of glucose metabolism, cell proliferation and apoptosis in the progression of OS. lncRNA XLOC_005950, hsa-miR-542-3p and PFKM expression in OS tissues and cells was detected via reverse transcription-quantitative PCR analysis. CRISPR/Cas9 gene editing was used to knockout lncRNA XLOC_005950 expression in MG63 cells. Cell Counting Kit-8 assay, flow cytometry, PFKM activity, and glucose and lactic acid content determination were performed to assess the effects of lncRNA XLOC_005950 knockout and overexpression of hsa-miR-542-3p on the phenotypes of OS cells. The dual-luciferase reporter assay was performed to confirm the targeting associations between lncRNA XLOC_005950, hsa-miR-542-3p and PFKM. The results demonstrated that lncRNA XLOC_005950 expression was upregulated in OS tissues and cells. Functional experiments indicated that lncRNA XLOC_005950 knockout decreased PFKM activity, the intracellular glucose and lactic acid content, and cell proliferation, while increasing apoptosis of OS cells. Furthermore, lncRNA XLOC_005950 knockout upregulated hsa-miR-542-3p expression and downregulated PFKM expression. Overexpression of hsa-miR-542-3p suppressed PFKM expression. Furthermore, lncRNA XLOC_005950, as the molecular sponge of miR-542-3p in OS, modulated the downstream target gene, PFKM. Taken together, the results of the present study suggest that lncRNA XLOC_005950 knockout may inhibit the progression of OS via hsa-miR-542-3p-mediated regulation of PFKM expression.
Collapse
Affiliation(s)
- Zhen Jia
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Yadong Wang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Xiaoya Sun
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Xuefeng Zhao
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Yan Zhang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Shuangyan Xu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| | - Yisheng Wang
- Department of Orthopaedic Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Yuebai Li
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou, Henan 450001, P.R. China
| |
Collapse
|
26
|
Fabry MH, Falconio FA, Joud F, Lythgoe EK, Czech B, Hannon GJ. Maternally inherited piRNAs direct transient heterochromatin formation at active transposons during early Drosophila embryogenesis. eLife 2021; 10:e68573. [PMID: 34236313 PMCID: PMC8352587 DOI: 10.7554/elife.68573] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/07/2021] [Indexed: 12/12/2022] Open
Abstract
The PIWI-interacting RNA (piRNA) pathway controls transposon expression in animal germ cells, thereby ensuring genome stability over generations. In Drosophila, piRNAs are intergenerationally inherited through the maternal lineage, and this has demonstrated importance in the specification of piRNA source loci and in silencing of I- and P-elements in the germ cells of daughters. Maternally inherited Piwi protein enters somatic nuclei in early embryos prior to zygotic genome activation and persists therein for roughly half of the time required to complete embryonic development. To investigate the role of the piRNA pathway in the embryonic soma, we created a conditionally unstable Piwi protein. This enabled maternally deposited Piwi to be cleared from newly laid embryos within 30 min and well ahead of the activation of zygotic transcription. Examination of RNA and protein profiles over time, and correlation with patterns of H3K9me3 deposition, suggests a role for maternally deposited Piwi in attenuating zygotic transposon expression in somatic cells of the developing embryo. In particular, robust deposition of piRNAs targeting roo, an element whose expression is mainly restricted to embryonic development, results in the deposition of transient heterochromatic marks at active roo insertions. We hypothesize that roo, an extremely successful mobile element, may have adopted a lifestyle of expression in the embryonic soma to evade silencing in germ cells.
Collapse
Affiliation(s)
- Martin H Fabry
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| | - Federica A Falconio
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| | - Fadwa Joud
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| | - Emily K Lythgoe
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| | - Benjamin Czech
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| | - Gregory J Hannon
- CRUK Cambridge Institute, University of Cambridge, Li Ka Shing CentreCambridgeUnited Kingdom
| |
Collapse
|
27
|
Binding of guide piRNA triggers methylation of the unstructured N-terminal region of Aub leading to assembly of the piRNA amplification complex. Nat Commun 2021; 12:4061. [PMID: 34210982 PMCID: PMC8249470 DOI: 10.1038/s41467-021-24351-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 06/10/2021] [Indexed: 11/08/2022] Open
Abstract
PIWI proteins use guide piRNAs to repress selfish genomic elements, protecting the genomic integrity of gametes and ensuring the fertility of animal species. Efficient transposon repression depends on amplification of piRNA guides in the ping-pong cycle, which in Drosophila entails tight cooperation between two PIWI proteins, Aub and Ago3. Here we show that post-translational modification, symmetric dimethylarginine (sDMA), of Aub is essential for piRNA biogenesis, transposon silencing and fertility. Methylation is triggered by loading of a piRNA guide into Aub, which exposes its unstructured N-terminal region to the PRMT5 methylosome complex. Thus, sDMA modification is a signal that Aub is loaded with piRNA guide. Amplification of piRNA in the ping-pong cycle requires assembly of a tertiary complex scaffolded by Krimper, which simultaneously binds the N-terminal regions of Aub and Ago3. To promote generation of new piRNA, Krimper uses its two Tudor domains to bind Aub and Ago3 in opposite modification and piRNA-loading states. Our results reveal that post-translational modifications in unstructured regions of PIWI proteins and their binding by Tudor domains that are capable of discriminating between modification states is essential for piRNA biogenesis and silencing.
Collapse
|
28
|
Joosten J, Taşköprü E, Jansen PWTC, Pennings B, Vermeulen M, Van Rij RP. PIWI proteomics identifies Atari and Pasilla as piRNA biogenesis factors in Aedes mosquitoes. Cell Rep 2021; 35:109073. [PMID: 33951430 DOI: 10.1016/j.celrep.2021.109073] [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: 10/02/2020] [Revised: 03/03/2021] [Accepted: 04/12/2021] [Indexed: 01/29/2023] Open
Abstract
As in most arthropods, the PIWI-interacting RNA (piRNA) pathway in the vector mosquito Aedes aegypti is active in diverse biological processes in both soma and germline. To gain insights into piRNA biogenesis and effector complexes, we mapped the interactomes of the somatic PIWI proteins Ago3, Piwi4, Piwi5, and Piwi6 and identify numerous specific interactors as well as cofactors associated with multiple PIWI proteins. We describe the Piwi5 interactor AAEL014965, the direct ortholog of the Drosophila splicing factor pasilla. We find that Ae. aegypti Pasilla encodes a nuclear isoform and a cytoplasmic isoform, the latter of which is required for efficient piRNA production. In addition, we characterize a splice variant of the Tudor protein AAEL008101/Atari that associates with Ago3 and forms a scaffold for PIWI proteins and target RNAs to promote ping-pong amplification of piRNAs. Our study provides a useful resource for follow-up studies of somatic piRNA biogenesis, mechanism, and function in Aedes mosquitoes.
Collapse
Affiliation(s)
- Joep Joosten
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Ezgi Taşköprü
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Pascal W T C Jansen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Oncode Institute, Radboud University Nijmegen, 6525 GA Nijmegen, the Netherlands
| | - Bas Pennings
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands
| | - Michiel Vermeulen
- Department of Molecular Biology, Faculty of Science, Radboud Institute for Molecular Life Sciences, Oncode Institute, Radboud University Nijmegen, 6525 GA Nijmegen, the Netherlands
| | - Ronald P Van Rij
- Department of Medical Microbiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, P.O. Box 9101, 6500 HB Nijmegen, the Netherlands.
| |
Collapse
|
29
|
Rozen-Gagnon K, Gu M, Luna JM, Luo JD, Yi S, Novack S, Jacobson E, Wang W, Paul MR, Scheel TKH, Carroll T, Rice CM. Argonaute-CLIP delineates versatile, functional RNAi networks in Aedes aegypti, a major vector of human viruses. Cell Host Microbe 2021; 29:834-848.e13. [PMID: 33794184 DOI: 10.1016/j.chom.2021.03.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/20/2021] [Accepted: 03/04/2021] [Indexed: 02/07/2023]
Abstract
Argonaute (AGO) proteins bind small RNAs to silence complementary RNA transcripts, and they are central to RNA interference (RNAi). RNAi is critical for regulation of gene expression and antiviral defense in Aedes aegypti mosquitoes, which transmit Zika, chikungunya, dengue, and yellow fever viruses. In mosquitoes, AGO1 mediates miRNA interactions, while AGO2 mediates siRNA interactions. We applied AGO-crosslinking immunoprecipitation (AGO-CLIP) for both AGO1 and AGO2, and we developed a universal software package for CLIP analysis (CLIPflexR), identifying 230 small RNAs and 5,447 small RNA targets that comprise a comprehensive RNAi network map in mosquitoes. RNAi network maps predicted expression levels of small RNA targets in specific tissues. Additionally, this resource identified unexpected, context-dependent AGO2 target preferences, including endogenous viral elements and 3'UTRs. Finally, contrary to current thinking, mosquito AGO2 repressed imperfect targets. These findings expand our understanding of small RNA networks and have broad implications for the study of antiviral RNAi.
Collapse
Affiliation(s)
- Kathryn Rozen-Gagnon
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA.
| | - Meigang Gu
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA
| | - Joseph M Luna
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA
| | - Ji-Dung Luo
- Bioinformatics Resource Center, the Rockefeller University, New York, NY 10065, USA
| | - Soon Yi
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA
| | - Sasha Novack
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA
| | - Eliana Jacobson
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA
| | - Wei Wang
- Bioinformatics Resource Center, the Rockefeller University, New York, NY 10065, USA
| | - Matthew R Paul
- Bioinformatics Resource Center, the Rockefeller University, New York, NY 10065, USA
| | - Troels K H Scheel
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA; Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases, Hvidovre Hospital, DK-2650 Hvidovre, Denmark; Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Thomas Carroll
- Bioinformatics Resource Center, the Rockefeller University, New York, NY 10065, USA
| | - Charles M Rice
- Laboratory of Virology and Infectious Disease, the Rockefeller University, New York, NY 10065, USA.
| |
Collapse
|
30
|
Parhad SS, Yu T, Zhang G, Rice NP, Weng Z, Theurkauf WE. Adaptive Evolution Targets a piRNA Precursor Transcription Network. Cell Rep 2021; 30:2672-2685.e5. [PMID: 32101744 PMCID: PMC7061269 DOI: 10.1016/j.celrep.2020.01.109] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 10/23/2019] [Accepted: 01/30/2020] [Indexed: 12/18/2022] Open
Abstract
In Drosophila, transposon-silencing piRNAs are derived from heterochromatic clusters and a subset of euchromatic transposon insertions, which are bound by the Rhino-Deadlock-Cutoff complex. The HP1 homolog Rhino binds to Deadlock, which recruits TRF2 to promote non-canonical transcription from both genomic strands. Cuff function is less well understood, but this Rai1 homolog shows hallmarks of adaptive evolution, which can remodel functional interactions within host defense systems. Supporting this hypothesis, Drosophila simulans Cutoff is a dominant-negative allele when expressed in Drosophila melanogaster, in which it traps Deadlock, TRF2, and the conserved transcriptional co-repressor CtBP in stable complexes. Cutoff functions with Rhino and Deadlock to drive non-canonical transcription. In contrast, CtBP suppresses canonical transcription of transposons and promoters flanking the major germline clusters, and canonical transcription interferes with downstream non-canonical transcription and piRNA production. Adaptive evolution thus targets interactions among Cutoff, TRF2, and CtBP that balance canonical and non-canonical piRNA precursor transcription.
Collapse
Affiliation(s)
- Swapnil S Parhad
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Tianxiong Yu
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA; School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Gen Zhang
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Nicholas P Rice
- Program in Molecular Medicine, 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.
| | - William E Theurkauf
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA.
| |
Collapse
|
31
|
Vrettos N, Maragkakis M, Alexiou P, Sgourdou P, Ibrahim F, Palmieri D, Kirino Y, Mourelatos Z. Modulation of Aub-TDRD interactions elucidates piRNA amplification and germplasm formation. Life Sci Alliance 2021; 4:e202000912. [PMID: 33376130 PMCID: PMC7772777 DOI: 10.26508/lsa.202000912] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 12/13/2020] [Accepted: 12/14/2020] [Indexed: 11/24/2022] Open
Abstract
Aub guided by piRNAs ensures genome integrity by cleaving retrotransposons, and genome propagation by trapping mRNAs to form the germplasm that instructs germ cell formation. Arginines at the N-terminus of Aub (Aub-NTRs) interact with Tudor and other Tudor domain-containing proteins (TDRDs). Aub-TDRD interactions suppress active retrotransposons via piRNA amplification and form germplasm via generation of Aub-Tudor ribonucleoproteins. Here, we show that Aub-NTRs are dispensable for primary piRNA biogenesis but essential for piRNA amplification and that their symmetric dimethylation is required for germplasm formation and germ cell specification but largely redundant for piRNA amplification.
Collapse
Affiliation(s)
- Nicholas Vrettos
- Division of Neuropathology, Departments of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Manolis Maragkakis
- Laboratory of Genetics and Genomics, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD, USA
| | | | - Paraskevi Sgourdou
- Departments of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Fadia Ibrahim
- Division of Neuropathology, Departments of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel Palmieri
- Division of Neuropathology, Departments of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Yohei Kirino
- Computational Medicine Center, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Zissimos Mourelatos
- Division of Neuropathology, Departments of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
32
|
Barbosa P, Zhaunova L, Debilio S, Steccanella V, Kelly V, Ly T, Ohkura H. SCF-Fbxo42 promotes synaptonemal complex assembly by downregulating PP2A-B56. J Cell Biol 2020; 220:211645. [PMID: 33382409 PMCID: PMC7780726 DOI: 10.1083/jcb.202009167] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 11/20/2020] [Accepted: 12/02/2020] [Indexed: 12/27/2022] Open
Abstract
Meiosis creates genetic diversity by recombination and segregation of chromosomes. The synaptonemal complex assembles during meiotic prophase I and assists faithful exchanges between homologous chromosomes, but how its assembly/disassembly is regulated remains to be understood. Here, we report how two major posttranslational modifications, phosphorylation and ubiquitination, cooperate to promote synaptonemal complex assembly. We found that the ubiquitin ligase complex SCF is important for assembly and maintenance of the synaptonemal complex in Drosophila female meiosis. This function of SCF is mediated by two substrate-recognizing F-box proteins, Slmb/βTrcp and Fbxo42. SCF-Fbxo42 down-regulates the phosphatase subunit PP2A-B56, which is important for synaptonemal complex assembly and maintenance.
Collapse
Affiliation(s)
- Pedro Barbosa
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Liudmila Zhaunova
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Simona Debilio
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK,Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Verdiana Steccanella
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Van Kelly
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Tony Ly
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Hiroyuki Ohkura
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK,Correspondence to Hiroyuki Ohkura:
| |
Collapse
|
33
|
Onishi R, Sato K, Murano K, Negishi L, Siomi H, Siomi MC. Piwi suppresses transcription of Brahma-dependent transposons via Maelstrom in ovarian somatic cells. SCIENCE ADVANCES 2020; 6:6/50/eaaz7420. [PMID: 33310860 PMCID: PMC7732180 DOI: 10.1126/sciadv.aaz7420] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 10/19/2020] [Indexed: 05/05/2023]
Abstract
Drosophila Piwi associates with PIWI-interacting RNAs (piRNAs) and represses transposons transcriptionally through heterochromatinization; however, this process is poorly understood. Here, we identify Brahma (Brm), the core adenosine triphosphatase of the SWI/SNF chromatin remodeling complex, as a new Piwi interactor, and show Brm involvement in activating transcription of Piwi-targeted transposons before silencing. Bioinformatic analyses indicated that Piwi, once bound to target RNAs, reduced the occupancies of SWI/SNF and RNA polymerase II (Pol II) on target loci, abrogating transcription. Artificial piRNA-driven targeting of Piwi to RNA transcripts enhanced repression of Brm-dependent reporters compared with Brm-independent reporters. This was dependent on Piwi cofactors, Gtsf1/Asterix (Gtsf1), Panoramix/Silencio (Panx), and Maelstrom (Mael), but not Eggless/dSetdb (Egg)-mediated H3K9me3 deposition. The λN-box B-mediated tethering of Mael to reporters repressed Brm-dependent genes in the absence of Piwi, Panx, and Gtsf1. We propose that Piwi, via Mael, can rapidly suppress transcription of Brm-dependent genes to facilitate heterochromatin formation.
Collapse
Affiliation(s)
- Ryo Onishi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan
| | - Kaoru Sato
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan
| | - Kensaku Murano
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Lumi Negishi
- Central Laboratory, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo 113-0032, Japan
| | - Haruhiko Siomi
- Department of Molecular Biology, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Mikiko C Siomi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan.
| |
Collapse
|
34
|
Rathore OS, Silva RD, Ascensão-Ferreira M, Matos R, Carvalho C, Marques B, Tiago MN, Prudêncio P, Andrade RP, Roignant JY, Barbosa-Morais NL, Martinho RG. NineTeen Complex-subunit Salsa is required for efficient splicing of a subset of introns and dorsal-ventral patterning. RNA (NEW YORK, N.Y.) 2020; 26:1935-1956. [PMID: 32963109 PMCID: PMC7668242 DOI: 10.1261/rna.077446.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 09/07/2020] [Indexed: 06/11/2023]
Abstract
The NineTeen Complex (NTC), also known as pre-mRNA-processing factor 19 (Prp19) complex, regulates distinct spliceosome conformational changes necessary for splicing. During Drosophila midblastula transition, splicing is particularly sensitive to mutations in NTC-subunit Fandango, which suggests differential requirements of NTC during development. We show that NTC-subunit Salsa, the Drosophila ortholog of human RNA helicase Aquarius, is rate-limiting for splicing of a subset of small first introns during oogenesis, including the first intron of gurken Germline depletion of Salsa and splice site mutations within gurken first intron impair both adult female fertility and oocyte dorsal-ventral patterning, due to an abnormal expression of Gurken. Supporting causality, the fertility and dorsal-ventral patterning defects observed after Salsa depletion could be suppressed by the expression of a gurken construct without its first intron. Altogether, our results suggest that one of the key rate-limiting functions of Salsa during oogenesis is to ensure the correct expression and efficient splicing of the first intron of gurken mRNA. Retention of gurken first intron compromises the function of this gene most likely because it undermines the correct structure and function of the transcript 5'UTR.
Collapse
Affiliation(s)
- Om Singh Rathore
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Rui D Silva
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Mariana Ascensão-Ferreira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Ricardo Matos
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Célia Carvalho
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Bruno Marques
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Margarida N Tiago
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
| | - Pedro Prudêncio
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Raquel P Andrade
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Department of Medicine and Biomedical Sciences and Algarve Biomedical Center, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Jean-Yves Roignant
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, CH-1015 Lausanne, Switzerland
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University Mainz, 55128 Mainz, Germany
| | - Nuno L Barbosa-Morais
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Rui Gonçalo Martinho
- Center for Biomedical Research (CBMR), Universidade do Algarve, Faro, 8005-139 Portugal
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Department of Medical Sciences and Institute for Biomedicine (iBiMED), Universidade de Aveiro, 3810-193 Aveiro, Portugal
| |
Collapse
|
35
|
Hsu SJ, Stow EC, Simmons JR, Wallace HA, Lopez AM, Stroud S, Labrador M. Mutations in the insulator protein Suppressor of Hairy wing induce genome instability. Chromosoma 2020; 129:255-274. [PMID: 33140220 DOI: 10.1007/s00412-020-00743-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/21/2020] [Accepted: 10/22/2020] [Indexed: 12/14/2022]
Abstract
Insulator proteins orchestrate the three-dimensional organization of the genome. Insulators function by facilitating communications between regulatory sequences and gene promoters, allowing accurate gene transcription regulation during embryo development and cell differentiation. However, the role of insulator proteins beyond genome organization and transcription regulation remains unclear. Suppressor of Hairy wing [Su(Hw)] is a Drosophila insulator protein that plays an important function in female oogenesis. Here we find that su(Hw) has an unsuspected role in genome stability during cell differentiation. We show that su(Hw) mutant developing egg chambers have poorly formed microtubule organization centers (MTOCs) in the germarium and display mislocalization of the anterior/posterior axis specification factor gurken in later oogenesis stages. Additionally, eggshells from partially rescued su(Hw) mutant female germline exhibit dorsoventral patterning defects. These phenotypes are very similar to phenotypes found in the important class of spindle mutants or in piRNA pathway mutants in Drosophila, in which defects generally result from the failure of germ cells to repair DNA damage. Similarities between mutations in su(Hw) and spindle and piRNA mutants are further supported by an excess of DNA damage in nurse cells, and because Gurken localization defects are partially rescued by mutations in the ATR (mei-41) and Chk1 (grapes) DNA damage response genes. Finally, we also show that su(Hw) mutants produce an elevated number of chromosome breaks in dividing neuroblasts from larval brains. Together, these findings suggest that Su(Hw) is necessary for the maintenance of genome integrity during Drosophila development, in both germline and dividing somatic cells.
Collapse
Affiliation(s)
- Shih-Jui Hsu
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Emily C Stow
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - James R Simmons
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Heather A Wallace
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Andrea Mancheno Lopez
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Shannon Stroud
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Mariano Labrador
- Department of Biochemistry and Cellular and Molecular Biology, The University of Tennessee, Knoxville, TN, 37996, USA.
| |
Collapse
|
36
|
Sukthaworn S, Panyim S, Udomkit A. Homologues of Piwi control transposable elements and development of male germline in Penaeus monodon. Comp Biochem Physiol A Mol Integr Physiol 2020; 250:110807. [PMID: 32971288 DOI: 10.1016/j.cbpa.2020.110807] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/09/2020] [Accepted: 09/11/2020] [Indexed: 10/23/2022]
Abstract
PIWI belongs to the Argonaute protein family, which is a major protein component in RNA silencing pathway. Piwi proteins play roles in the control of transposons and germline development. They have been widely studied in vertebrates and flies, while very little is known in crustacean so far. We have previously identified and characterized a cDNA encoding Piwi protein (PmPiwi1) in the black tiger shrimp Penaeus monodon. In this study, a cDNA encoding another Piwi protein namely PmPiwi2 was identified by rapid amplification of cDNA ends (RACEs). PmPiwi2 was expressed solely in shrimp testis and ovary, indicating its potential role in germ cell development. Similar to PmPiwi1, PmPiwi2 also plays a part in the control of transposons as PmPiwi2-knockdown shrimp showed a significant increase in the expression of gypsy2 retrotransposon and mariner element in the testis. In addition, a reduction of sperm numbers in the spermatophore of PmPiwi2-knockdown shrimp suggests that PmPiwi2 is required for spermatogenesis similar to PmPiwi1. This study further demonstrated that apoptotic cell death was strongly detected in spermatogonia and spermatocyte cells of both PmPiwi-knockdown shrimp and thus, could be the cause of reduced sperm count. Investigation of sperm morphology showed a remarkably high proportion of abnormal sperms in the spermatophore of the PmPiwi1-knockdown shrimp, while PmPiwi2-knockdown shrimp had comparable percentage of abnormal sperms to the control shrimp. Consistently, the expression of KIFC1, a gene that is necessary for spermiogenesis was significantly reduced upon PmPiwi1 silencing, but not in the PmPiwi2-knockdown shrimp. Our results suggested that while both PmPiwis are required for the development of spermatid, only PmPiwi1 is possibly involved in the final stage of sperm maturation.
Collapse
Affiliation(s)
- Suchitraporn Sukthaworn
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakhon Pathom 73170, Thailand
| | - Sakol Panyim
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakhon Pathom 73170, Thailand; Department of Biochemistry, Faculty of Sciences, Mahidol University, Rama VI Road, Phayathai, Bangkok 10400, Thailand
| | - Apinunt Udomkit
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Nakhon Pathom 73170, Thailand.
| |
Collapse
|
37
|
Piwi reduction in the aged niche eliminates germline stem cells via Toll-GSK3 signaling. Nat Commun 2020; 11:3147. [PMID: 32561720 PMCID: PMC7305233 DOI: 10.1038/s41467-020-16858-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 05/30/2020] [Indexed: 12/13/2022] Open
Abstract
Transposons are known to participate in tissue aging, but their effects on aged stem cells remain unclear. Here, we report that in the Drosophila ovarian germline stem cell (GSC) niche, aging-related reductions in expression of Piwi (a transposon silencer) derepress retrotransposons and cause GSC loss. Suppression of Piwi expression in the young niche mimics the aged niche, causing retrotransposon depression and coincident activation of Toll-mediated signaling, which promotes Glycogen synthase kinase 3 activity to degrade β-catenin. Disruption of β-catenin-E-cadherin-mediated GSC anchorage then results in GSC loss. Knocking down gypsy (a highly active retrotransposon) or toll, or inhibiting reverse transcription in the piwi-deficient niche, suppresses GSK3 activity and β-catenin degradation, restoring GSC-niche attachment. This retrotransposon-mediated impairment of aged stem cell maintenance may have relevance in many tissues, and could represent a viable therapeutic target for aging-related tissue degeneration.
Collapse
|
38
|
Kochanova NY, Schauer T, Mathias GP, Lukacs A, Schmidt A, Flatley A, Schepers A, Thomae AW, Imhof A. A multi-layered structure of the interphase chromocenter revealed by proximity-based biotinylation. Nucleic Acids Res 2020; 48:4161-4178. [PMID: 32182352 PMCID: PMC7192626 DOI: 10.1093/nar/gkaa145] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 12/26/2022] Open
Abstract
During interphase centromeres often coalesce into a small number of chromocenters, which can be visualized as distinct, DAPI dense nuclear domains. Intact chromocenters play a major role in maintaining genome stability as they stabilize the transcriptionally silent state of repetitive DNA while ensuring centromere function. Despite its biological importance, relatively little is known about the molecular composition of the chromocenter or the processes that mediate chromocenter formation and maintenance. To provide a deeper molecular insight into the composition of the chromocenter and to demonstrate the usefulness of proximity-based biotinylation as a tool to investigate those questions, we performed super resolution microscopy and proximity-based biotinylation experiments of three distinct proteins associated with the chromocenter in Drosophila. Our work revealed an intricate internal architecture of the chromocenter suggesting a complex multilayered structure of this intranuclear domain.
Collapse
Affiliation(s)
- Natalia Y Kochanova
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Tamas Schauer
- Biomedical Center, Bioinformatics Core Facility, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Grusha Primal Mathias
- Biomedical Center, Core Facility Bioimaging, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andrea Lukacs
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andreas Schmidt
- Biomedical Center, Protein Analysis Unit, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andrew Flatley
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility and Research Group Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Aloys Schepers
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility and Research Group Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Andreas W Thomae
- Biomedical Center, Core Facility Bioimaging, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Axel Imhof
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
- Biomedical Center, Protein Analysis Unit, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| |
Collapse
|
39
|
Abstract
Transposons are major genome constituents that can mobilize and trigger mutations, DNA breaks and chromosome rearrangements. Transposon silencing is particularly important in the germline, which is dedicated to transmission of the inherited genome. Piwi-interacting RNAs (piRNAs) guide a host defence system that transcriptionally and post-transcriptionally silences transposons during germline development. While germline control of transposons by the piRNA pathway is conserved, many piRNA pathway genes are evolving rapidly under positive selection, and the piRNA biogenesis machinery shows remarkable phylogenetic diversity. Conservation of core function combined with rapid gene evolution is characteristic of a host–pathogen arms race, suggesting that transposons and the piRNA pathway are engaged in an evolutionary tug of war that is driving divergence of the biogenesis machinery. Recent studies suggest that this process may produce biochemical incompatibilities that contribute to reproductive isolation and species divergence.
Collapse
Affiliation(s)
- Swapnil S Parhad
- Program in Molecular Medicine, University of Massachusetts Medical School , 373 Plantation Street, Worcester, MA 01605 , USA
| | - William E Theurkauf
- Program in Molecular Medicine, University of Massachusetts Medical School , 373 Plantation Street, Worcester, MA 01605 , USA
| |
Collapse
|
40
|
Stolyarenko AD. Nuclear Argonaute Piwi Gene Mutation Affects rRNA by Inducing rRNA Fragment Accumulation, Antisense Expression, and Defective Processing in Drosophila Ovaries. Int J Mol Sci 2020; 21:ijms21031119. [PMID: 32046213 PMCID: PMC7037970 DOI: 10.3390/ijms21031119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 01/27/2020] [Accepted: 02/04/2020] [Indexed: 12/26/2022] Open
Abstract
Drosophila key nuclear piRNA silencing pathway protein Piwi of the Argonaute family has been classically studied as a factor controlling transposable elements and fertility. Piwi has been shown to concentrate in the nucleolus for reasons largely unknown. Ribosomal RNA is the main component of the nucleolus. In this work the effect of a piwi mutation on rRNA is described. This work led to three important conclusions: A mutation in piwi induces antisense 5S rRNA expression, a processing defect of 2S rRNA orthologous to the 3′-end of eukaryotic 5.8S rRNA, and accumulation of fragments of all five rRNAs in Drosophilamelanogaster ovaries. Hypotheses to explain these phenomena are proposed, possibly involving the interaction of the components of the piRNA pathway with the RNA surveillance machinery.
Collapse
Affiliation(s)
- Anastasia D Stolyarenko
- Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., Moscow 123182, Russia
| |
Collapse
|
41
|
Sokolova OA, Mikhaleva EA, Kharitonov SL, Abramov YA, Gvozdev VA, Klenov MS. Special vulnerability of somatic niche cells to transposable element activation in Drosophila larval ovaries. Sci Rep 2020; 10:1076. [PMID: 31974416 PMCID: PMC6978372 DOI: 10.1038/s41598-020-57901-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 01/07/2020] [Indexed: 01/09/2023] Open
Abstract
In the Drosophila ovary, somatic escort cells (ECs) form a niche that promotes differentiation of germline stem cell (GSC) progeny. The piRNA (Piwi-interacting RNA) pathway, which represses transposable elements (TEs), is required in ECs to prevent the accumulation of undifferentiated germ cells (germline tumor phenotype). The soma-specific piRNA cluster flamenco (flam) produces a substantial part of somatic piRNAs. Here, we characterized the biological effects of somatic TE activation on germ cell differentiation in flam mutants. We revealed that the choice between normal and tumorous phenotypes of flam mutant ovaries depends on the number of persisting ECs, which is determined at the larval stage. Accordingly, we found much more frequent DNA breaks in somatic cells of flam larval ovaries than in adult ECs. The absence of Chk2 or ATM checkpoint kinases dramatically enhanced oogenesis defects of flam mutants, in contrast to the germline TE-induced defects that are known to be mostly suppressed by сhk2 mutation. These results demonstrate a crucial role of checkpoint kinases in protecting niche cells against deleterious TE activation and suggest substantial differences between DNA damage responses in ovarian somatic and germ cells.
Collapse
Affiliation(s)
- Olesya A Sokolova
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation
| | - Elena A Mikhaleva
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation
| | - Sergey L Kharitonov
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation
- Laboratory of Postgenomic Research, Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilova St., 119991, Moscow, Russian Federation
| | - Yuri A Abramov
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation
| | - Vladimir A Gvozdev
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation
| | - Mikhail S Klenov
- Department of Molecular Genetics of the Cell, Institute of Molecular Genetics, Russian Academy of Sciences, 2 Kurchatov Sq., 123182, Moscow, Russian Federation.
| |
Collapse
|
42
|
Eichler CE, Hakes AC, Hull B, Gavis ER. Compartmentalized oskar degradation in the germ plasm safeguards germline development. eLife 2020; 9:49988. [PMID: 31909715 PMCID: PMC6986870 DOI: 10.7554/elife.49988] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Accepted: 01/07/2020] [Indexed: 12/13/2022] Open
Abstract
Partitioning of mRNAs into ribonucleoprotein (RNP) granules supports diverse regulatory programs within the crowded cytoplasm. At least two types of RNP granules populate the germ plasm, a cytoplasmic domain at the posterior of the Drosophila oocyte and embryo. Germ granules deliver mRNAs required for germline development to pole cells, the germ cell progenitors. A second type of RNP granule, here named founder granules, contains oskar mRNA, which encodes the germ plasm organizer. Whereas oskar mRNA is essential for germ plasm assembly during oogenesis, we show that it is toxic to pole cells. Founder granules mediate compartmentalized degradation of oskar during embryogenesis to minimize its inheritance by pole cells. Degradation of oskar in founder granules is temporally and mechanistically distinct from degradation of oskar and other mRNAs during the maternal-to-zygotic transition. Our results show how compartmentalization in RNP granules differentially controls fates of mRNAs localized within the same cytoplasmic domain.
Collapse
Affiliation(s)
- Catherine E Eichler
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Anna C Hakes
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Brooke Hull
- Department of Molecular Biology, Princeton University, Princeton, United States
| | - Elizabeth R Gavis
- Department of Molecular Biology, Princeton University, Princeton, United States
| |
Collapse
|
43
|
Ninova M, Chen YCA, Godneeva B, Rogers AK, Luo Y, Fejes Tóth K, Aravin AA. Su(var)2-10 and the SUMO Pathway Link piRNA-Guided Target Recognition to Chromatin Silencing. Mol Cell 2019; 77:556-570.e6. [PMID: 31901446 DOI: 10.1016/j.molcel.2019.11.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 06/11/2019] [Accepted: 11/08/2019] [Indexed: 01/14/2023]
Abstract
Regulation of transcription is the main mechanism responsible for precise control of gene expression. Whereas the majority of transcriptional regulation is mediated by DNA-binding transcription factors that bind to regulatory gene regions, an elegant alternative strategy employs small RNA guides, Piwi-interacting RNAs (piRNAs) to identify targets of transcriptional repression. Here, we show that in Drosophila the small ubiquitin-like protein SUMO and the SUMO E3 ligase Su(var)2-10 are required for piRNA-guided deposition of repressive chromatin marks and transcriptional silencing of piRNA targets. Su(var)2-10 links the piRNA-guided target recognition complex to the silencing effector by binding the piRNA/Piwi complex and inducing SUMO-dependent recruitment of the SetDB1/Wde histone methyltransferase effector. We propose that in Drosophila, the nuclear piRNA pathway has co-opted a conserved mechanism of SUMO-dependent recruitment of the SetDB1/Wde chromatin modifier to confer repression of genomic parasites.
Collapse
Affiliation(s)
- Maria Ninova
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA
| | - Yung-Chia Ariel Chen
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA
| | - Baira Godneeva
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA; Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia
| | - Alicia K Rogers
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA
| | - Yicheng Luo
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA
| | - Katalin Fejes Tóth
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA.
| | - Alexei A Aravin
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, Pasadena, CA 91125, USA.
| |
Collapse
|
44
|
Kotov AA, Adashev VE, Godneeva BK, Ninova M, Shatskikh AS, Bazylev SS, Aravin AA, Olenina LV. piRNA silencing contributes to interspecies hybrid sterility and reproductive isolation in Drosophila melanogaster. Nucleic Acids Res 2019; 47:4255-4271. [PMID: 30788506 PMCID: PMC6486647 DOI: 10.1093/nar/gkz130] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 02/12/2019] [Accepted: 02/16/2019] [Indexed: 12/05/2022] Open
Abstract
The piRNA pathway is an adaptive mechanism that maintains genome stability by repression of selfish genomic elements. In the male germline of Drosophila melanogaster repression of Stellate genes by piRNAs generated from Supressor of Stellate (Su(Ste)) locus is required for male fertility, but both Su(Ste) piRNAs and their targets are absent in other Drosophila species. We found that D. melanogaster genome contains multiple X-linked non-coding genomic repeats that have sequence similarity to the protein-coding host gene vasa. In the male germline, these vasa-related AT-chX repeats produce abundant piRNAs that are antisense to vasa; however, vasa mRNA escapes silencing due to imperfect complementarity to AT-chX piRNAs. Unexpectedly, we discovered AT-chX piRNAs target vasa of Drosophila mauritiana in the testes of interspecies hybrids. In the majority of hybrid flies, the testes were strongly reduced in size and germline content. A minority of hybrids maintained wild-type array of premeiotic germ cells in the testes, but in them harmful Stellate genes were derepressed due to the absence of Su(Ste) piRNAs, and meiotic failures were observed. Thus, the piRNA pathway contributes to reproductive isolation between D. melanogaster and closely related species, causing hybrid male sterility via misregulation of two different host protein factors.
Collapse
Affiliation(s)
- Alexei A Kotov
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| | - Vladimir E Adashev
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| | - Baira K Godneeva
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| | - Maria Ninova
- California Institute of Technology, Division of Biology and Biological Engineering, 147-75, 1200 E. California Blvd., Pasadena, CA 91125, USA
| | - Aleksei S Shatskikh
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| | - Sergei S Bazylev
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| | - Alexei A Aravin
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia.,California Institute of Technology, Division of Biology and Biological Engineering, 147-75, 1200 E. California Blvd., Pasadena, CA 91125, USA
| | - Ludmila V Olenina
- Institute of Molecular Genetics, Russian Academy of Sciences, Kurchatov Sq. 2, Moscow, 123182 Russia
| |
Collapse
|
45
|
Durdevic Z, Ephrussi A. Germ Cell Lineage Homeostasis in Drosophila Requires the Vasa RNA Helicase. Genetics 2019; 213:911-922. [PMID: 31484689 PMCID: PMC6827371 DOI: 10.1534/genetics.119.302558] [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: 07/24/2019] [Accepted: 08/29/2019] [Indexed: 11/18/2022] Open
Abstract
The conserved RNA helicase Vasa is required for germ cell development in many organisms. In Drosophila melanogaster loss of PIWI-interacting RNA pathway components, including Vasa, causes Chk2-dependent oogenesis arrest. However, whether the arrest is due to Chk2 signaling at a specific stage and whether continuous Chk2 signaling is required for the arrest is unknown. Here, we show that absence of Vasa during the germarial stages causes Chk2-dependent oogenesis arrest. Additionally, we report the age-dependent decline of the ovariole number both in flies lacking Vasa expression only in the germarium and in loss-of-function vasa mutant flies. We show that Chk2 activation exclusively in the germarium is sufficient to interrupt oogenesis and to reduce ovariole number in aging flies. Once induced in the germarium, Chk2-mediated arrest of germ cell development cannot be overcome by restoration of Vasa or by downregulation of Chk2 in the arrested egg chambers. These findings, together with the identity of Vasa-associated proteins identified in this study, demonstrate an essential role of the helicase in the germ cell lineage maintenance and indicate a function of Vasa in germline stem cell homeostasis.
Collapse
Affiliation(s)
- Zeljko Durdevic
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg D-69117, Germany
| | - Anne Ephrussi
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg D-69117, Germany
| |
Collapse
|
46
|
Story B, Ma X, Ishihara K, Li H, Hall K, Peak A, Anoja P, Park J, Haug J, Blanchette M, Xie T. Defining the expression of piRNA and transposable elements in Drosophila ovarian germline stem cells and somatic support cells. Life Sci Alliance 2019; 2:2/5/e201800211. [PMID: 31619466 PMCID: PMC6796194 DOI: 10.26508/lsa.201800211] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 10/01/2019] [Accepted: 10/04/2019] [Indexed: 11/26/2022] Open
Abstract
Comprehensive transcriptional characterization of mRNA and small RNA in early Drosophila germline stem cells reveals novel piRNA clusters, transposon dynamics, and alternative splicing events. Piwi-interacting RNAs (piRNAs) are important for repressing transposable elements (TEs) and modulating gene expression in germ cells, thereby maintaining genome stability and germ cell function. Although they are also important for maintaining germline stem cells (GSCs) in the Drosophila ovary by repressing TEs and preventing DNA damage, piRNA expression has not been investigated in GSCs or their early progeny. Here, we show that the canonical piRNA clusters are more active in GSCs and their early progeny than late germ cells and also identify more than 3,000 new piRNA clusters from deep sequencing data. The increase in piRNAs in GSCs and early progeny can be attributed to both canonical and newly identified piRNA clusters. As expected, piRNA clusters in GSCs, but not those in somatic support cells (SCs), exhibit ping-pong signatures. Surprisingly, GSCs and early progeny express more TE transcripts than late germ cells, suggesting that the increase in piRNA levels may be related to the higher levels of TE transcripts in GSCs and early progeny. GSCs also have higher piRNA levels and lower TE levels than SCs. Furthermore, the 3′ UTRs of 171 mRNA transcripts may produce sense, antisense, or dual-stranded piRNAs. Finally, we show that alternative promoter usage and splicing are frequently used to modulate gene function in GSCs and SCs. Overall, this study has provided important insight into piRNA production and TE repression in GSCs and SCs. The rich information provided by this study will be a beneficial resource to the fields of piRNA biology and germ cell development.
Collapse
Affiliation(s)
- Benjamin Story
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Xing Ma
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Kazue Ishihara
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Hua Li
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Kathryn Hall
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Allison Peak
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Perera Anoja
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Jungeun Park
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Jeff Haug
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | | | - Ting Xie
- Stowers Institute for Medical Research, Kansas City, MO, USA
| |
Collapse
|
47
|
Casier K, Boivin A, Carré C, Teysset L. Environmentally-Induced Transgenerational Epigenetic Inheritance: Implication of PIWI Interacting RNAs. Cells 2019; 8:cells8091108. [PMID: 31546882 PMCID: PMC6770481 DOI: 10.3390/cells8091108] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 12/11/2022] Open
Abstract
Environmentally-induced transgenerational epigenetic inheritance is an emerging field. The understanding of associated epigenetic mechanisms is currently in progress with open questions still remaining. In this review, we present an overview of the knowledge of environmentally-induced transgenerational inheritance and associated epigenetic mechanisms, mainly in animals. The second part focuses on the role of PIWI-interacting RNAs (piRNAs), a class of small RNAs involved in the maintenance of the germline genome, in epigenetic memory to put into perspective cases of environmentally-induced transgenerational inheritance involving piRNA production. Finally, the last part addresses how genomes are facing production of new piRNAs, and from a broader perspective, how this process might have consequences on evolution and on sporadic disease development.
Collapse
Affiliation(s)
- Karine Casier
- Transgenerational Epigenetics & small RNA Biology, Sorbonne Université, CNRS, Laboratoire Biologie du Développement, Institut de Biologie Paris-Seine, UMR7622, 75005 Paris, France.
| | - Antoine Boivin
- Transgenerational Epigenetics & small RNA Biology, Sorbonne Université, CNRS, Laboratoire Biologie du Développement, Institut de Biologie Paris-Seine, UMR7622, 75005 Paris, France.
| | - Clément Carré
- Transgenerational Epigenetics & small RNA Biology, Sorbonne Université, CNRS, Laboratoire Biologie du Développement, Institut de Biologie Paris-Seine, UMR7622, 75005 Paris, France.
| | - Laure Teysset
- Transgenerational Epigenetics & small RNA Biology, Sorbonne Université, CNRS, Laboratoire Biologie du Développement, Institut de Biologie Paris-Seine, UMR7622, 75005 Paris, France.
| |
Collapse
|
48
|
Grendler J, Lowgren S, Mills M, Losick VP. Wound-induced polyploidization is driven by Myc and supports tissue repair in the presence of DNA damage. Development 2019; 146:dev.173005. [PMID: 31315896 PMCID: PMC6703715 DOI: 10.1242/dev.173005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 07/05/2019] [Indexed: 12/19/2022]
Abstract
Tissue repair usually requires either polyploid cell growth or cell division, but the molecular mechanism promoting polyploidy and limiting cell division remains poorly understood. Here, we find that injury to the adult Drosophila epithelium causes cells to enter the endocycle through the activation of Yorkie-dependent genes (Myc and E2f1). Myc is even sufficient to induce the endocycle in the uninjured post-mitotic epithelium. As result, epithelial cells enter S phase but mitosis is blocked by inhibition of mitotic gene expression. The mitotic cell cycle program can be activated by simultaneously expressing the Cdc25-like phosphatase String (stg), while genetically depleting APC/C E3 ligase fizzy-related (fzr). However, forcing cells to undergo mitosis is detrimental to wound repair as the adult fly epithelium accumulates DNA damage, and mitotic errors ensue when cells are forced to proliferate. In conclusion, we find that wound-induced polyploidization enables tissue repair when cell division is not a viable option.
Collapse
Affiliation(s)
- Janelle Grendler
- Kathryn W. Davis Center for Regenerative Biology and Medicine, MDI Biological Laboratory, 159 Old Bar Harbor Rd, Bar Harbor, ME 04609, USA
| | - Sara Lowgren
- Kathryn W. Davis Center for Regenerative Biology and Medicine, MDI Biological Laboratory, 159 Old Bar Harbor Rd, Bar Harbor, ME 04609, USA
| | - Monique Mills
- Kathryn W. Davis Center for Regenerative Biology and Medicine, MDI Biological Laboratory, 159 Old Bar Harbor Rd, Bar Harbor, ME 04609, USA
| | - Vicki P Losick
- Kathryn W. Davis Center for Regenerative Biology and Medicine, MDI Biological Laboratory, 159 Old Bar Harbor Rd, Bar Harbor, ME 04609, USA
| |
Collapse
|
49
|
Ozata DM, Gainetdinov I, Zoch A, O'Carroll D, Zamore PD. PIWI-interacting RNAs: small RNAs with big functions. Nat Rev Genet 2019; 20:89-108. [PMID: 30446728 DOI: 10.1038/s41576-018-0073-3] [Citation(s) in RCA: 630] [Impact Index Per Article: 126.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In animals, PIWI-interacting RNAs (piRNAs) of 21-35 nucleotides in length silence transposable elements, regulate gene expression and fight viral infection. piRNAs guide PIWI proteins to cleave target RNA, promote heterochromatin assembly and methylate DNA. The architecture of the piRNA pathway allows it both to provide adaptive, sequence-based immunity to rapidly evolving viruses and transposons and to regulate conserved host genes. piRNAs silence transposons in the germ line of most animals, whereas somatic piRNA functions have been lost, gained and lost again across evolution. Moreover, most piRNA pathway proteins are deeply conserved, but different animals employ remarkably divergent strategies to produce piRNA precursor transcripts. Here, we discuss how a common piRNA pathway allows animals to recognize diverse targets, ranging from selfish genetic elements to genes essential for gametogenesis.
Collapse
Affiliation(s)
- Deniz M Ozata
- RNA Therapeutics Institute and Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ildar Gainetdinov
- RNA Therapeutics Institute and Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ansgar Zoch
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Dónal O'Carroll
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.,Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, UK
| | - Phillip D Zamore
- RNA Therapeutics Institute and Howard Hughes Medical Institute, University of Massachusetts Medical School, Worcester, MA, USA.
| |
Collapse
|
50
|
Small RNA-Seq Analysis Reveals miRNA Expression Dynamics Across Tissues in the Malaria Vector, Anopheles gambiae. G3-GENES GENOMES GENETICS 2019; 9:1507-1517. [PMID: 30846481 PMCID: PMC6505144 DOI: 10.1534/g3.119.400104] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Malaria continues to be a major global health problem, where disease transmission is deeply linked to the repeated blood feeding nature of the anautogenous mosquito. Given the tight link between blood feeding and disease transmission, understanding basic biology behind mosquito physiology is a requirement for developing effective vector-borne disease control strategies. In the mosquito, numerous loss of function studies with notable phenotypes demonstrate microRNAs (miRNAs) play significant roles in mosquito physiology. While the field appreciates the importance of a handful of miRNAs, we still need global mosquito tissue miRNA transcriptome studies. To address this need, our goal was to determine the miRNA transcriptome for multiple tissues of the pre-vitellogenic mosquito. To this end, by using small RNA-Seq analysis, we determined miRNA transcriptomes in tissues critical for mosquito reproduction and immunity including (i) fat body-abdominal wall enriched tissues, (ii) midguts, (iii) ovaries, and (iv) remaining tissues comprised of the head and thorax. We found numerous examples of miRNAs exhibiting pan-tissue high- or low- expression, tissue exclusion, and tissue enrichment. We also updated and consolidated the miRNA catalog and provided a detailed genome architecture map for the malaria vector, Anopheles gambiae. This study aims to build a foundation for future research on how miRNAs and potentially other small RNAs regulate mosquito physiology as it relates to vector-borne disease transmission.
Collapse
|