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Erdmann EA, Forbes M, Becker M, Perez S, Hundley HA. ADR-2 regulates fertility and oocyte fate in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.01.565157. [PMID: 37961348 PMCID: PMC10635048 DOI: 10.1101/2023.11.01.565157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
RNA binding proteins play essential roles in coordinating germline gene expression and development in all organisms. Here, we report that loss of ADR-2, a member of the Adenosine DeAminase acting on RNA (ADAR) family of RNA binding proteins and the sole adenosine-to-inosine RNA editing enzyme in C. elegans, can improve fertility in multiple genetic backgrounds. First, we show that loss of RNA editing by ADR-2 restores normal embryo production to subfertile animals that transgenically express a vitellogenin (yolk protein) fusion to green fluorescent protein. Using this phenotype, a high-throughput screen was designed to identify RNA binding proteins that when depleted yield synthetic phenotypes with loss of adr-2. The screen uncovered a genetic interaction between ADR-2 and SQD-1, a member of the heterogenous nuclear ribonucleoprotein (hnRNP) family of RNA binding proteins. Microscopy, reproductive assays, and high-throughput sequencing reveal that sqd-1 is essential for the onset of oogenesis and oogenic gene expression in young adult animals, and that loss of adr-2 can counteract the effects of loss of sqd-1 on gene expression and rescue the switch from spermatogenesis to oogenesis. Together, these data demonstrate that ADR-2 can contribute to the suppression of fertility and suggest novel roles for both RNA editing-dependent and independent mechanisms in regulating embryogenesis.
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Affiliation(s)
- Emily A Erdmann
- Genome, Cell and Developmental Biology Graduate Program, Indiana University, Bloomington IN, US 47405
| | - Melanie Forbes
- Department of Biology, Indiana University, Bloomington IN, US 47405
| | - Margaret Becker
- Medical Sciences Program, Indiana University School of Medicine-Bloomington, Bloomington IN, US 47405
| | - Sarina Perez
- Department of Biology, Indiana University, Bloomington IN, US 47405
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2
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Wahiduzzaman, Tindell SJ, Alexander E, Hackney E, Kharel K, Schmidtke R, Arkov AL. Drosophila germ granules are assembled from protein components through different modes of competing interactions with the multi-domain Tudor protein. FEBS Lett 2024; 598:774-786. [PMID: 38499396 DOI: 10.1002/1873-3468.14846] [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: 09/06/2023] [Revised: 12/21/2023] [Accepted: 02/14/2024] [Indexed: 03/20/2024]
Abstract
Membraneless organelles are RNA-protein assemblies which have been implicated in post-transcriptional control. Germ cells form membraneless organelles referred to as germ granules, which contain conserved proteins including Tudor domain-containing scaffold polypeptides and their partner proteins that interact with Tudor domains. Here, we show that in Drosophila, different germ granule proteins associate with the multi-domain Tudor protein using different numbers of Tudor domains. Furthermore, these proteins compete for interaction with Tudor in vitro and, surprisingly, partition to distinct and poorly overlapping clusters in germ granules in vivo. This partition results in minimization of the competition. Our data suggest that Tudor forms structurally different configurations with different partner proteins which dictate different biophysical properties and phase separation parameters within the same granule.
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Affiliation(s)
- Wahiduzzaman
- Department of Biological Sciences, Murray State University, KY, USA
| | - Samuel J Tindell
- Department of Biological Sciences, Murray State University, KY, USA
| | - Emma Alexander
- Department of Biological Sciences, Murray State University, KY, USA
| | - Ethan Hackney
- Department of Biological Sciences, Murray State University, KY, USA
| | - Kabita Kharel
- Department of Biological Sciences, Murray State University, KY, USA
| | - Ryan Schmidtke
- Department of Biological Sciences, Murray State University, KY, USA
| | - Alexey L Arkov
- Department of Biological Sciences, Murray State University, KY, USA
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3
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Zhang R, Li S, Feng W, Qian S, Chellappa AJ, Wang F. Rim4 is a Thermal Sensor and Driver of Meiosis-specific Stress Granules. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.09.574866. [PMID: 38260504 PMCID: PMC10802437 DOI: 10.1101/2024.01.09.574866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Rim4 is a meiosis-specific RNA-binding protein (RBP) that sequesters mRNAs to suppress their translation. Previous work has defined the Rim4 C-terminal low-complexity domain (LCD) as sequences that form self-propagating amyloid-like aggregates. Here, we uncovered a dynamic and reversible form of Rim4 self-assembly primarily triggered by heat during meiosis, proportionally from 30°C to 42°C. The formed thermal Rim4 condensates in cell promptly stimulates stress granule (SG) assembly, recruiting SG-resident proteins, such as Pab1 and Pbp1, and strikingly, decreases the required temperature for meiotic SG formation (∼33°C) by ∼9°C as compared to mitosis (∼42°C). This sensitization of meiotic SG formation to heat effectively prevents meiosis progression and sporulation under harmful thermal turbulence. Meanwhile, the Rim4-positive meiotic SGs protect Rim4 and Rim4-sequestered mRNAs from autophagy to allow a rapid recovery from stalled meiosis upon the stress relief. Mechanistically, we found that the yeast 14-3-3 proteins (Bmh1 and Bmh2) and nucleic acids brake initiation of heat-induced Rim4 self-assembly, and Hsp104 facilitates the restoration of intracellular Rim4 distribution during the recovery.
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4
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Harisa GI, Faris TM, Sherif AY, Alzhrani RF, Alanazi SA, Kohaf NA, Alanazi FK. Gene-editing technology, from macromolecule therapeutics to organ transplantation: Applications, limitations, and prospective uses. Int J Biol Macromol 2023; 253:127055. [PMID: 37758106 DOI: 10.1016/j.ijbiomac.2023.127055] [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: 04/04/2023] [Revised: 09/04/2023] [Accepted: 09/15/2023] [Indexed: 10/03/2023]
Abstract
Gene editing technologies (GETs) could induce gene knockdown or gene knockout for biomedical applications. The clinical success of gene silence by RNAi therapies pays attention to other GETs as therapeutic approaches. This review aims to highlight GETs, categories, mechanisms, challenges, current use, and prospective applications. The different academic search engines, electronic databases, and bibliographies of selected articles were used in the preparation of this review with a focus on the fundamental considerations. The present results revealed that, among GETs, CRISPR/Cas9 has higher editing efficiency and targeting specificity compared to other GETs to insert, delete, modify, or replace the gene at a specific location in the host genome. Therefore, CRISPR/Cas9 is talented in the production of molecular, tissue, cell, and organ therapies. Consequently, GETs could be used in the discovery of innovative therapeutics for genetic diseases, pandemics, cancer, hopeless diseases, and organ failure. Specifically, GETs have been used to produce gene-modified animals to spare human organ failure. Genetically modified pigs are used in clinical trials as a source of heart, liver, kidneys, and lungs for xenotransplantation (XT) in humans. Viral, non-viral, and hybrid vectors have been utilized for the delivery of GETs with some limitations. Therefore, extracellular vesicles (EVs) are proposed as intelligent and future cargoes for GETs delivery in clinical applications. This study concluded that GETs are promising for the production of molecular, cellular, and organ therapies. The use of GETs as XT is still in the early stage as well and they have ethical and biosafety issues.
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Affiliation(s)
- Gamaleldin I Harisa
- Kayyali Chair for Pharmaceutical Industry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Biochemistry and Molecular Biology, College of Pharmacy, Al-Azhar University, Nasr City, Cairo, Egypt.
| | - Tarek M Faris
- Department of Pharmaceutical Sciences, College of Pharmacy, Princess Nourah bint Abdulrahman University, Saudi Arabia
| | - Abdelrahman Y Sherif
- Kayyali Chair for Pharmaceutical Industry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Riyad F Alzhrani
- Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Nanobiotechnology Research Unit, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Saleh A Alanazi
- Pharmaceutical Care Services, King Abdulaziz Medical City, King Saud bin Abdulaziz University for Health Science Collage of Pharmacy, King Abdullah International Medical Research Center, Riyadh, Saudi Arabia
| | - Neveen A Kohaf
- Department of Clinical Pharmacy, Faculty of Pharmacy, Al-Azhar University, Cairo 11651, Egypt
| | - Fars K Alanazi
- Kayyali Chair for Pharmaceutical Industry, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
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5
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Ow MC, Hall SE. Inheritance of Stress Responses via Small Non-Coding RNAs in Invertebrates and Mammals. EPIGENOMES 2023; 8:1. [PMID: 38534792 DOI: 10.3390/epigenomes8010001] [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: 10/06/2023] [Revised: 12/06/2023] [Accepted: 12/12/2023] [Indexed: 03/28/2024] Open
Abstract
While reports on the generational inheritance of a parental response to stress have been widely reported in animals, the molecular mechanisms behind this phenomenon have only recently emerged. The booming interest in epigenetic inheritance has been facilitated in part by the discovery that small non-coding RNAs are one of its principal conduits. Discovered 30 years ago in the Caenorhabditis elegans nematode, these small molecules have since cemented their critical roles in regulating virtually all aspects of eukaryotic development. Here, we provide an overview on the current understanding of epigenetic inheritance in animals, including mice and C. elegans, as it pertains to stresses such as temperature, nutritional, and pathogenic encounters. We focus on C. elegans to address the mechanistic complexity of how small RNAs target their cohort mRNAs to effect gene expression and how they govern the propagation or termination of generational perdurance in epigenetic inheritance. Presently, while a great amount has been learned regarding the heritability of gene expression states, many more questions remain unanswered and warrant further investigation.
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Affiliation(s)
- Maria C Ow
- Department of Biology, Syracuse University, Syracuse, NY 13210, USA
| | - Sarah E Hall
- Department of Biology and Program in Neuroscience, Syracuse University, Syracuse, NY 13210, USA
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6
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Woodruff GC, Willis JH, Johnson E, Phillips PC. Widespread changes in gene expression accompany body size evolution in nematodes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.30.564729. [PMID: 37961435 PMCID: PMC10635002 DOI: 10.1101/2023.10.30.564729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Body size is a fundamental trait that drives multiple evolutionary and ecological patterns. Caenorhabditis inopinata is a fig-associated nematode that is exceptionally large relative to other members of the genus, including C. elegans. We previously showed that C. inopinata is large primarily due to postembryonic cell size expansion that occurs during the larval-to-adult transition. Here, we describe gene expression patterns in C. elegans and C. inopinata throughout this developmental period to understand the transcriptional basis of body size change. We performed RNA-seq in both species across the L3, L4, and adult stages. Most genes are differentially expressed across all developmental stages, consistent with C. inopinata's divergent ecology and morphology. We also used a model comparison approach to identify orthologs with divergent dynamics across this developmental period between the two species. This included genes connected to neurons, behavior, stress response, developmental timing, and small RNA/chromatin regulation. Multiple hypodermal collagens were also observed to harbor divergent developmental dynamics across this period, and genes important for molting and body morphology were also detected. Genes associated with TGF-β signaling revealed idiosyncratic and unexpected transcriptional patterns given their role in body size regulation in C. elegans. Widespread transcriptional divergence between these species is unexpected and may be a signature of the ecological and morphological divergence of C. inopinata. Alternatively, transcriptional turnover may be the rule in the Caenorhabditis genus, indicative of widespread developmental system drift among species. This work lays the foundation for future functional genetic studies interrogating the bases of body size evolution in this group.
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Affiliation(s)
- Gavin C Woodruff
- University of Oregon, Eugene, Oregon, USA
- Current institution: University of Oklahoma, Norman, Oklahoma, USA
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7
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Rieger I, Weintraub G, Lev I, Goldstein K, Bar-Zvi D, Anava S, Gingold H, Shaham S, Rechavi O. Nucleus-independent transgenerational small RNA inheritance in Caenorhabditis elegans. SCIENCE ADVANCES 2023; 9:eadj8618. [PMID: 37878696 PMCID: PMC10599617 DOI: 10.1126/sciadv.adj8618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/20/2023] [Indexed: 10/27/2023]
Abstract
In Caenorhabditis elegans worms, epigenetic information transmits transgenerationally. Still, it is unknown whether the effects transfer to the next generation inside or outside of the nucleus. Here, we use the tractability of gene-specific double-stranded RNA-induced silencing to demonstrate that RNA interference can be inherited independently of any nuclear factors via mothers that are genetically engineered to transmit only their ooplasm but not the oocytes' nuclei to the next generation. We characterize the mechanisms and, using RNA sequencing, chimeric worms, and sequence polymorphism between different isolates, identify endogenous small RNAs which, similarly to exogenous siRNAs, are inherited in a nucleus-independent manner. From a historical perspective, these results might be regarded as partial vindication of discredited cytoplasmic inheritance theories from the 19th century, such as Darwin's "pangenesis" theory.
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Affiliation(s)
- Itai Rieger
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Guy Weintraub
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Itamar Lev
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Kesem Goldstein
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Dana Bar-Zvi
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Sarit Anava
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Hila Gingold
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, New York, NY, USA
| | - Oded Rechavi
- Department of Neurobiology, Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
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8
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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.
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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
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9
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Hirose T, Ninomiya K, Nakagawa S, Yamazaki T. A guide to membraneless organelles and their various roles in gene regulation. Nat Rev Mol Cell Biol 2023; 24:288-304. [PMID: 36424481 DOI: 10.1038/s41580-022-00558-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 88.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2022] [Indexed: 11/25/2022]
Abstract
Membraneless organelles (MLOs) are detected in cells as dots of mesoscopic size. By undergoing phase separation into a liquid-like or gel-like phase, MLOs contribute to intracellular compartmentalization of specific biological functions. In eukaryotes, dozens of MLOs have been identified, including the nucleolus, Cajal bodies, nuclear speckles, paraspeckles, promyelocytic leukaemia protein (PML) nuclear bodies, nuclear stress bodies, processing bodies (P bodies) and stress granules. MLOs contain specific proteins, of which many possess intrinsically disordered regions (IDRs), and nucleic acids, mainly RNA. Many MLOs contribute to gene regulation by different mechanisms. Through sequestration of specific factors, MLOs promote biochemical reactions by simultaneously concentrating substrates and enzymes, and/or suppressing the activity of the sequestered factors elsewhere in the cell. Other MLOs construct inter-chromosomal hubs by associating with multiple loci, thereby contributing to the biogenesis of macromolecular machineries essential for gene expression, such as ribosomes and spliceosomes. The organization of many MLOs includes layers, which might have different biophysical properties and functions. MLOs are functionally interconnected and are involved in various diseases, prompting the emergence of therapeutics targeting them. In this Review, we introduce MLOs that are relevant to gene regulation and discuss their assembly, internal structure, gene-regulatory roles in transcription, RNA processing and translation, particularly in stress conditions, and their disease relevance.
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Affiliation(s)
- Tetsuro Hirose
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.
- Institute for Open and Transdisciplinary Research Initiatives, Osaka University, Suita, Japan.
| | - Kensuke Ninomiya
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
| | - Shinichi Nakagawa
- Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Tomohiro Yamazaki
- Graduate School of Frontier Biosciences, Osaka University, Suita, Japan
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10
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Suen KM, Sheard TM, Lin CC, Milonaityte D, Jayasinghe I, Ladbury JE. Expansion microscopy reveals subdomains in C. elegans germ granules. Life Sci Alliance 2023; 6:e202201650. [PMID: 36750365 PMCID: PMC9905708 DOI: 10.26508/lsa.202201650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 02/09/2023] Open
Abstract
Light and electron microscopy techniques have been indispensable in the identification and characterization of liquid-liquid phase separation membraneless organelles. However, for complex membraneless organelles such as the perinuclear germ granule in C. elegans, our understanding of how the intact organelle is regulated is hampered by (1) technical limitations in confocal fluorescence imaging for the simultaneous examination of multiple granule protein markers and (2) inaccessibility of electron microscopy. We take advantage of the newly developed super resolution method of expansion microscopy (ExM) and in situ staining of the whole proteome to examine the C. elegans germ granule, the P granule. We show that in small RNA pathway mutants, the P granule is smaller compared with WT animals. Furthermore, we investigate the relationship between the P granule and two other germ granules, Mutator foci and Z granule, and show that they are located within the same protein-dense regions while occupying distinct subdomains within this ultrastructure. This study will serve as an important tool in our understanding of germ granule biology and the biological role of liquid-liquid phase separation.
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Affiliation(s)
- Kin M Suen
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | | | - Chi-Chuan Lin
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Dovile Milonaityte
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Izzy Jayasinghe
- School of Biosciences, University of Sheffield, Sheffield, UK
| | - John E Ladbury
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
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11
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Seroussi U, Lugowski A, Wadi L, Lao RX, Willis AR, Zhao W, Sundby AE, Charlesworth AG, Reinke AW, Claycomb JM. A comprehensive survey of C. elegans argonaute proteins reveals organism-wide gene regulatory networks and functions. eLife 2023; 12:e83853. [PMID: 36790166 PMCID: PMC10101689 DOI: 10.7554/elife.83853] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 02/14/2023] [Indexed: 02/16/2023] Open
Abstract
Argonaute (AGO) proteins associate with small RNAs to direct their effector function on complementary transcripts. The nematode Caenorhabditis elegans contains an expanded family of 19 functional AGO proteins, many of which have not been fully characterized. In this work, we systematically analyzed every C. elegans AGO using CRISPR-Cas9 genome editing to introduce GFP::3xFLAG tags. We have characterized the expression patterns of each AGO throughout development, identified small RNA binding complements, and determined the effects of ago loss on small RNA populations and developmental phenotypes. Our analysis indicates stratification of subsets of AGOs into distinct regulatory modules, and integration of our data led us to uncover novel stress-induced fertility and pathogen response phenotypes due to ago loss.
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Affiliation(s)
- Uri Seroussi
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | - Andrew Lugowski
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | - Lina Wadi
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | - Robert X Lao
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | | | - Winnie Zhao
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | - Adam E Sundby
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | | | - Aaron W Reinke
- Department of Molecular Genetics, University of TorontoTorontoCanada
| | - Julie M Claycomb
- Department of Molecular Genetics, University of TorontoTorontoCanada
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12
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Gleason RJ, Chen X. Epigenetic dynamics during germline development: insights from Drosophila and C. elegans. Curr Opin Genet Dev 2023; 78:102017. [PMID: 36549194 PMCID: PMC10100592 DOI: 10.1016/j.gde.2022.102017] [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: 10/03/2022] [Revised: 11/08/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
Gametogenesis produces the only cell type within a metazoan that contributes both genetic and epigenetic information to the offspring. Extensive epigenetic dynamics are required to express or repress gene expression in a precise spatiotemporal manner. On the other hand, early embryos must be extensively reprogrammed as they begin a new life cycle, involving intergenerational epigenetic inheritance. Seminal work in both Drosophila and C. elegans has elucidated the role of various regulators of epigenetic inheritance, including (1) histones, (2) histone-modifying enzymes, and (3) small RNA-dependent epigenetic regulation in the maintenance of germline identity. This review highlights recent discoveries of epigenetic regulation during the stepwise changes of transcription and chromatin structure that takes place during germline stem cell self-renewal, maintenance of germline identity, and intergenerational epigenetic inheritance. Findings from these two species provide precedence and opportunity to extend relevant studies to vertebrates.
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Affiliation(s)
- Ryan J. Gleason
- Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
| | - Xin Chen
- HHMI, Department of Biology, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
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13
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Spradling AC, Niu W, Yin Q, Pathak M, Maurya B. Conservation of oocyte development in germline cysts from Drosophila to mouse. eLife 2022; 11:83230. [PMID: 36445738 PMCID: PMC9708067 DOI: 10.7554/elife.83230] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Accepted: 11/17/2022] [Indexed: 11/30/2022] Open
Abstract
Recent studies show that pre-follicular mouse oogenesis takes place in germline cysts, highly conserved groups of oogonial cells connected by intercellular bridges that develop as nurse cells as well as an oocyte. Long studied in Drosophila and insect gametogenesis, female germline cysts acquire cytoskeletal polarity and traffic centrosomes and organelles between nurse cells and the oocyte to form the Balbiani body, a conserved marker of polarity. Mouse oocyte development and nurse cell dumping are supported by dynamic, cell-specific programs of germline gene expression. High levels of perinatal germ cell death in this species primarily result from programmed nurse cell turnover after transfer rather than defective oocyte production. The striking evolutionary conservation of early oogenesis mechanisms between distant animal groups strongly suggests that gametogenesis and early embryonic development in vertebrates and invertebrates share even more in common than currently believed.
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Affiliation(s)
- Allan C Spradling
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Wanbao Niu
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Qi Yin
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Madhulika Pathak
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
| | - Bhawana Maurya
- Carnegie Institution for Science/Howard Hughes Medical Institute, Baltimore, United States
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14
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Guzman DM, Chakka K, Shi T, Marron A, Fiorito AE, Rahman NS, Ro S, Sucich DG, Pierce JT. Transgenerational effects of alcohol on behavioral sensitivity to alcohol in Caenorhabditis elegans. PLoS One 2022; 17:e0271849. [PMID: 36256641 PMCID: PMC9578632 DOI: 10.1371/journal.pone.0271849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022] Open
Abstract
Alcohol abuse and dependence have a substantial heritable component. Although the genome has been considered the sole vehicle of heritable phenotypes, recent studies suggest that drug or alcohol exposure may induce alterations in gene expression that are transmitted across generations. Still, the transgenerational impact of alcohol use (and abuse) remains largely unexplored in part because multigenerational studies using rodent models present challenges for time, sample size, and genetic heterogeneity. Here, we took advantage of the extremely short generation time, large broods, and clonal form of reproduction of the nematode Caenorhabditis elegans. We developed a model of pre-fertilization parental alcohol exposure to test alterations in behavioral responses to acute alcohol treatment (referred to in short as intoxication) in subsequent F1, F2 and F3 generations. We found that chronic and intermittent alcohol-treatment paradigms resulted in opposite changes to intoxication sensitivity of F3 progeny that were only apparent when controlling for yoked trials. Chronic alcohol-treatment paradigm in the parental generation resulted in alcohol-naïve F3 progeny displaying moderate resistance to intoxication. Intermittent treatment resulted in alcohol-naïve F3 progeny displaying moderate hypersensitivity to intoxication. Further study of these phenomena using this new C. elegans model may yield mechanistic insights into how transgenerational effects may occur in other animals.
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Affiliation(s)
- Dawn M. Guzman
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Keerthana Chakka
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Ted Shi
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Alyssa Marron
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Ansley E. Fiorito
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Nima S. Rahman
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Stephanie Ro
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
| | - Dylan G. Sucich
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jonathan T. Pierce
- Department of Neuroscience, Waggoner Center for Alcohol and Addiction Research, Center for Learning and Memory, University of Texas at Austin, Austin, Texas, United States of America
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15
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Pang TY. Cross Talk opposing view: The kids will be fine - a bit of parental stress won't affect them: Rodents are not good models for assessing transgenerational influences in humans. J Physiol 2022; 600:4413-4416. [PMID: 36184260 DOI: 10.1113/jp282410] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 07/06/2022] [Indexed: 12/18/2022] Open
Affiliation(s)
- Terence Y Pang
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, Australia.,Department of Anatomy & Physiology, The University of Melbourne, VIC, Australia
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16
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Elaswad MT, Watkins BM, Sharp KG, Munderloh C, Schisa JA. Large RNP granules in Caenorhabditis elegans oocytes have distinct phases of RNA-binding proteins. G3 GENES|GENOMES|GENETICS 2022; 12:6639704. [PMID: 35816006 PMCID: PMC9434171 DOI: 10.1093/g3journal/jkac173] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 06/24/2022] [Indexed: 11/14/2022]
Abstract
The germ line provides an excellent in vivo system to study the regulation and function of RNP granules. Germ granules are conserved germ line-specific RNP granules that are positioned in the Caenorhabditis elegans adult gonad to function in RNA maintenance, regulation, and surveillance. In Caenorhabditis elegans, when oogenesis undergoes extended meiotic arrest, germ granule proteins and other RNA-binding proteins assemble into much larger RNP granules whose hypothesized function is to regulate RNA metabolism and maintain oocyte quality. To gain insight into the function of oocyte RNP granules, in this report, we characterize distinct phases for four protein components of RNP granules in arrested oocytes. We find that the RNA-binding protein PGL-1 is dynamic and has liquid-like properties, while the intrinsically disordered protein MEG-3 has gel-like properties, similar to the properties of the two proteins in small germ granules of embryos. We find that MEX-3 exhibits several gel-like properties but is more dynamic than MEG-3, while CGH-1 is dynamic but does not consistently exhibit liquid-like characteristics and may be an intermediate phase within RNP granules. These distinct phases of RNA-binding proteins correspond to, and may underlie, differential responses to stress. Interestingly, in oocyte RNP granules, MEG-3 is not required for the condensation of PGL-1 or other RNA-binding proteins, which differs from the role of MEG-3 in small, embryonic germ granules. Lastly, we show that the PUF-5 translational repressor appears to promote MEX-3 and MEG-3 condensation into large RNP granules; however, this role may be associated with regulation of oogenesis.
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Affiliation(s)
- Mohamed T Elaswad
- Biochemistry, Cell and Molecular Biology Program, Central Michigan University , Mt. Pleasant, MI 48859, USA
- Department of Biology, Central Michigan University , Mt. Pleasant, MI 48859, USA
| | - Brooklynne M Watkins
- Biochemistry, Cell and Molecular Biology Program, Central Michigan University , Mt. Pleasant, MI 48859, USA
- Department of Biology, Central Michigan University , Mt. Pleasant, MI 48859, USA
| | - Katherine G Sharp
- Department of Biology, Central Michigan University , Mt. Pleasant, MI 48859, USA
| | - Chloe Munderloh
- Department of Biology, Central Michigan University , Mt. Pleasant, MI 48859, USA
| | - Jennifer A Schisa
- Biochemistry, Cell and Molecular Biology Program, Central Michigan University , Mt. Pleasant, MI 48859, USA
- Department of Biology, Central Michigan University , Mt. Pleasant, MI 48859, USA
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17
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Carro MDLM, Grimson A, Cohen PE. Small RNAs and their protein partners in animal meiosis. Curr Top Dev Biol 2022; 151:245-279. [PMID: 36681472 DOI: 10.1016/bs.ctdb.2022.06.001] [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] [Indexed: 01/25/2023]
Abstract
Meiosis is characterized by highly regulated transitions in gene expression that require diverse mechanisms of gene regulation. For example, in male mammals, transcription undergoes a global shut-down in early prophase I of meiosis, followed by increasing transcriptional activity into pachynema. Later, as spermiogenesis proceeds, the histones bound to DNA are replaced with transition proteins, which are themselves replaced with protamines, resulting in a highly condensed nucleus with repressed transcriptional activity. In addition, two specialized gene silencing events take place during prophase I: meiotic silencing of unsynapsed chromatin (MSUC), and the sex chromatin specific mechanism, meiotic sex chromosome inactivation (MSCI). Notably, conserved roles for the RNA binding protein (RBP) machinery that functions with small non-coding RNAs have been described as participating in these meiosis-specific mechanisms, suggesting that RNA-mediated gene regulation is critical for fertility in many species. Here, we review roles of small RNAs and their associated RBPs in meiosis-related processes such as centromere function, silencing of unpaired chromatin and meiotic recombination. We will discuss the emerging evidence of non-canonical functions of these components in meiosis.
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Affiliation(s)
- María de Las Mercedes Carro
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, United States; Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States
| | - Andrew Grimson
- Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States; Department of Molecular Biology & Genetics, Cornell University, Ithaca, NY, United States.
| | - Paula E Cohen
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, United States; Cornell Reproductive Sciences Center (CoRe), Cornell University, Ithaca, NY, United States.
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18
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Nikonorova IA, Wang J, Cope AL, Tilton PE, Power KM, Walsh JD, Akella JS, Krauchunas AR, Shah P, Barr MM. Isolation, profiling, and tracking of extracellular vesicle cargo in Caenorhabditis elegans. Curr Biol 2022; 32:1924-1936.e6. [PMID: 35334227 PMCID: PMC9491618 DOI: 10.1016/j.cub.2022.03.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 01/26/2022] [Accepted: 03/01/2022] [Indexed: 01/04/2023]
Abstract
Extracellular vesicles (EVs) may mediate intercellular communication by carrying protein and RNA cargo. The composition, biology, and roles of EVs in physiology and pathology have been primarily studied in the context of biofluids and in cultured mammalian cells. The experimental tractability of C. elegans makes for a powerful in vivo animal system to identify and study EV cargo from its cellular source. We developed an innovative method to label, track, and profile EVs using genetically encoded, fluorescent-tagged EV cargo and conducted a large-scale isolation and proteomic profiling. Nucleic acid binding proteins (∼200) are overrepresented in our dataset. By integrating our EV proteomic dataset with single-cell transcriptomic data, we identified and validated ciliary EV cargo: CD9-like tetraspanin (TSP-6), ectonucleotide pyrophosphatase/phosphodiesterase (ENPP-1), minichromosome maintenance protein (MCM-3), and double-stranded RNA transporter SID-2. C. elegans EVs also harbor RNA, suggesting that EVs may play a role in extracellular RNA-based communication.
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Affiliation(s)
- Inna A Nikonorova
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA.
| | - Juan Wang
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Alexander L Cope
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Peter E Tilton
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Kaiden M Power
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Jonathon D Walsh
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Jyothi S Akella
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Amber R Krauchunas
- University of Delaware, Department of Biological Sciences, 105 The Green, Newark, DE 19716, USA
| | - Premal Shah
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA
| | - Maureen M Barr
- Rutgers, The State University of New Jersey, Department of Genetics and Human Genetics Institute of New Jersey Piscataway, 145 Bevier Road, Piscataway, NJ 08854, USA.
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19
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Zagoskin MV, Wang J, Neff AT, Veronezi GMB, Davis RE. Small RNA pathways in the nematode Ascaris in the absence of piRNAs. Nat Commun 2022; 13:837. [PMID: 35149688 PMCID: PMC8837657 DOI: 10.1038/s41467-022-28482-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 01/13/2022] [Indexed: 02/07/2023] Open
Abstract
Small RNA pathways play key and diverse regulatory roles in C. elegans, but our understanding of their conservation and contributions in other nematodes is limited. We analyzed small RNA pathways in the divergent parasitic nematode Ascaris. Ascaris has ten Argonautes with five worm-specific Argonautes (WAGOs) that associate with secondary 5’-triphosphate 22-24G-RNAs. These small RNAs target repetitive sequences or mature mRNAs and are similar to the C. elegans mutator, nuclear, and CSR-1 small RNA pathways. Even in the absence of a piRNA pathway, Ascaris CSR-1 may still function to “license” as well as fine-tune or repress gene expression. Ascaris ALG-4 and its associated 26G-RNAs target and likely repress specific mRNAs during testis meiosis. Ascaris WAGO small RNAs demonstrate target plasticity changing their targets between repeats and mRNAs during development. We provide a unique and comprehensive view of mRNA and small RNA expression throughout spermatogenesis. Overall, our study illustrates the conservation, divergence, dynamics, and flexibility of small RNA pathways in nematodes. The parasitic nematode Ascaris lacks piRNAs. Here the authors compare Argonaute proteins and small RNAs from C. elegans and Ascaris, expanding our understanding of the conservation, divergence, and flexibility of Argonautes and small RNA pathways in nematodes.
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Affiliation(s)
- Maxim V Zagoskin
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA.,RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA.,Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA
| | - Jianbin Wang
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA. .,RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA. .,Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, USA. .,UT-ORNL Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN, USA.
| | - Ashley T Neff
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Giovana M B Veronezi
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Richard E Davis
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, USA. .,RNA Bioscience Initiative, University of Colorado School of Medicine, Aurora, CO, USA.
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20
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Sperm granules mediate epigenetic inheritance. Nat Cell Biol 2022; 24:129-130. [DOI: 10.1038/s41556-021-00832-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Ouyang JPT, Seydoux G. Nuage condensates: accelerators or circuit breakers for sRNA silencing pathways? RNA (NEW YORK, N.Y.) 2022; 28:58-66. [PMID: 34772788 PMCID: PMC8675287 DOI: 10.1261/rna.079003.121] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nuage are RNA-rich condensates that assemble around the nuclei of developing germ cells. Many proteins required for the biogenesis and function of silencing small RNAs (sRNAs) enrich in nuage, and it is often assumed that nuage is the cellular site where sRNAs are synthesized and encounter target transcripts for silencing. Using C. elegans as a model, we examine the complex multicondensate architecture of nuage and review evidence for compartmentalization of silencing pathways. We consider the possibility that nuage condensates balance the activity of competing sRNA pathways and serve to limit, rather than enhance, sRNA amplification to protect transcripts from dangerous runaway silencing.
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Affiliation(s)
- John Paul Tsu Ouyang
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Geraldine Seydoux
- HHMI and Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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22
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Charlesworth AG, Nitschko V, Renaud MS, Claycomb JM. PIWI puts spermatogenesis in its place. Dev Cell 2022; 57:149-151. [DOI: 10.1016/j.devcel.2022.01.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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23
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Seroussi U, Li C, Sundby AE, Lee TL, Claycomb JM, Saltzman AL. Mechanisms of epigenetic regulation by C. elegans nuclear RNA interference pathways. Semin Cell Dev Biol 2021; 127:142-154. [PMID: 34876343 DOI: 10.1016/j.semcdb.2021.11.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/17/2021] [Accepted: 11/17/2021] [Indexed: 01/06/2023]
Abstract
RNA interference (RNAi) is a highly conserved gene regulatory phenomenon whereby Argonaute/small RNA (AGO/sRNA) complexes target transcripts by antisense complementarity to modulate gene expression. While initially appreciated as a cytoplasmic process, RNAi can also occur in the nucleus where AGO/sRNA complexes are recruited to nascent transcripts. Nuclear AGO/sRNA complexes recruit co-factors that regulate transcription by inhibiting RNA Polymerase II, modifying histones, compacting chromatin and, in some organisms, methylating DNA. C. elegans has a longstanding history in unveiling the mechanisms of RNAi and has become an outstanding model to delineate the mechanisms underlying nuclear RNAi. In this review we highlight recent discoveries in the field of nuclear RNAi in C. elegans and the roles of nuclear RNAi in the regulation of gene expression, chromatin organization, genome stability, and transgenerational epigenetic inheritance.
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Affiliation(s)
- Uri Seroussi
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Chengyin Li
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Adam E Sundby
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada
| | - Tammy L Lee
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Julie M Claycomb
- Department of Molecular Genetics, University of Toronto, Toronto, ON, Canada.
| | - Arneet L Saltzman
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada.
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24
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Abstract
DNA is central to the propagation and evolution of most living organisms due to the essential process of its self-replication. Yet it also encodes factors that permit epigenetic (not included in DNA sequence) flow of information from parents to their offspring and beyond. The known mechanisms of epigenetic inheritance include chemical modifications of DNA and chromatin, as well as regulatory RNAs. All these factors can modulate gene expression programs in the ensuing generations. The nematode Caenorhabditis elegans is recognized as a pioneer organism in transgenerational epigenetic inheritance research. Recent advances in C. elegans epigenetics include the discoveries of control mechanisms that limit the duration of RNA-based epigenetic inheritance, periodic DNA motifs that counteract epigenetic silencing establishment, new mechanistic insights into epigenetic inheritance carried by sperm, and the tantalizing examples of inheritance of sensory experiences. This review aims to highlight new findings in epigenetics research in C. elegans with the main focus on transgenerational epigenetic phenomena dependent on small RNAs.
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Affiliation(s)
- Alla Grishok
- Department of Biochemistry, BU Genome Science Institute, Boston University School of Medicine, 72 E. Concord St. K422, Boston, MA 02118, USA
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25
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Xiao H, Vierling MM, Kennedy RF, Boone EC, Decker LM, Sy VT, Haynes JB, Williams MA, Shiu PKT. Involvement of RNA granule proteins in meiotic silencing by unpaired DNA. G3 (BETHESDA, MD.) 2021; 11:jkab179. [PMID: 34568932 PMCID: PMC8482848 DOI: 10.1093/g3journal/jkab179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/13/2021] [Indexed: 11/14/2022]
Abstract
In Neurospora crassa, expression from an unpaired gene is suppressed by a mechanism known as meiotic silencing by unpaired DNA (MSUD). MSUD utilizes common RNA interference (RNAi) factors to silence target mRNAs. Here, we report that Neurospora CAR-1 and CGH-1, homologs of two Caenorhabditis elegans RNA granule components, are involved in MSUD. These fungal proteins are found in the perinuclear region and P-bodies, much like their worm counterparts. They interact with components of the meiotic silencing complex (MSC), including the SMS-2 Argonaute. This is the first time MSUD has been linked to RNA granule proteins.
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Affiliation(s)
- Hua Xiao
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Michael M Vierling
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Rana F Kennedy
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Erin C Boone
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Logan M Decker
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Victor T Sy
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Jackson B Haynes
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Michelle A Williams
- Present address: Department of Biology, McMaster University, Hamilton, ON L8S 4K1, Canada
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Patrick K T Shiu
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
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26
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Charlesworth AG, Seroussi U, Lehrbach NJ, Renaud MS, Sundby AE, Molnar RI, Lao RX, Willis AR, Woock JR, Aber MJ, Diao AJ, Reinke AW, Ruvkun G, Claycomb JM. Two isoforms of the essential C. elegans Argonaute CSR-1 differentially regulate sperm and oocyte fertility. Nucleic Acids Res 2021; 49:8836-8865. [PMID: 34329465 PMCID: PMC8421154 DOI: 10.1093/nar/gkab619] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 07/01/2021] [Accepted: 07/19/2021] [Indexed: 01/09/2023] Open
Abstract
The Caenorhabditis elegans genome encodes nineteen functional Argonaute proteins that use 22G-RNAs, 26G-RNAs, miRNAs or piRNAs to regulate target transcripts. Only one Argonaute is essential under normal laboratory conditions: CSR-1. While CSR-1 has been studied widely, nearly all studies have overlooked the fact that the csr-1 locus encodes two isoforms. These isoforms differ by an additional 163 amino acids present in the N-terminus of CSR-1a. Using CRISPR-Cas9 genome editing to introduce GFP::3xFLAG into the long (CSR-1a) and short (CSR-1b) isoforms, we found that CSR-1a is expressed during spermatogenesis and in several somatic tissues, including the intestine. CSR-1b is expressed constitutively in the germline. small RNA sequencing of CSR-1 complexes shows that they interact with partly overlapping sets of 22G-RNAs. Phenotypic analyses reveal that the essential functions of csr-1 described in the literature coincide with CSR-1b, while CSR-1a plays tissue specific functions. During spermatogenesis, CSR-1a integrates into an sRNA regulatory network including ALG-3, ALG-4 and WAGO-10 that is necessary for fertility at 25°C. In the intestine, CSR-1a silences immunity and pathogen-responsive genes, and its loss results in improved survival from the pathogen Pseudomonas aeruginosa. Our findings functionally distinguish the CSR-1 isoforms and highlight the importance of studying each AGO isoform independently.
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Affiliation(s)
| | - Uri Seroussi
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Nicolas J Lehrbach
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Mathias S Renaud
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Adam E Sundby
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Ruxandra I Molnar
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Robert X Lao
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Alexandra R Willis
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Jenna R Woock
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Matthew J Aber
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Annette J Diao
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Aaron W Reinke
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
| | - Gary Ruvkun
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.,Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Julie M Claycomb
- Department of Molecular Genetics, University of Toronto Toronto, ON M5S 1A8 Canada
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27
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Uebel CJ, Manage KI, Phillips CM. SIMR foci are found in the progenitor germ cells of C. elegans embryos. MICROPUBLICATION BIOLOGY 2021; 2021. [PMID: 33644707 PMCID: PMC7900827 DOI: 10.17912/micropub.biology.000374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
RNA interference is a widely conserved mechanism of gene regulation and silencing across eukaryotes. In C. elegans, RNA silencing is coordinated through perinuclear nuage containing at least four granules: P granules, Z granules, Mutator foci, and SIMR foci. Embryonic localization of these granules is known for all except SIMR foci. Here we establish that SIMR foci first appear at the nuclear periphery in the P4 germline blastomere and become numerous and bright in the Z2 and Z3 progenitor germ cells. This timing coincides with the appearance or de-mixing of other germline granules, providing further evidence for coordinated germ granule reorganization.
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Affiliation(s)
- Celja J Uebel
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Kevin I Manage
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
| | - Carolyn M Phillips
- Department of Biological Sciences, University of Southern California, Los Angeles, California, USA
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