1
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Frédérick PM, Jannot G, Banville I, Simard M. Interaction between a J-domain co-chaperone and a specific Argonaute protein contributes to microRNA function in animals. Nucleic Acids Res 2024; 52:6253-6268. [PMID: 38613392 PMCID: PMC11194074 DOI: 10.1093/nar/gkae272] [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: 08/18/2023] [Revised: 03/27/2024] [Accepted: 04/03/2024] [Indexed: 04/14/2024] Open
Abstract
MicroRNAs (miRNAs) are essential regulators of several biological processes. They are loaded onto Argonaute (AGO) proteins to achieve their repressive function, forming the microRNA-Induced Silencing Complex known as miRISC. While several AGO proteins are expressed in plants and animals, it is still unclear why specific AGOs are strictly binding miRNAs. Here, we identified the co-chaperone DNJ-12 as a new interactor of ALG-1, one of the two major miRNA-specific AGOs in Caenorhabditis elegans. DNJ-12 does not interact with ALG-2, the other major miRNA-specific AGO, and PRG-1 and RDE-1, two AGOs involved in other small RNA pathways, making it a specific actor in ALG-1-dependent miRNA-mediated gene silencing. The loss of DNJ-12 causes developmental defects associated with defective miRNA function. Using the Auxin Inducible Degron system, a powerful tool to acutely degrade proteins in specific tissues, we show that DNJ-12 depletion hampers ALG-1 interaction with HSP70, a chaperone required for miRISC loading in vitro. Moreover, DNJ-12 depletion leads to the decrease of several miRNAs and prevents their loading onto ALG-1. This study uncovers the importance of a co-chaperone for the miRNA function in vivo and provides insights to explain how different small RNAs associate with specific AGO in animals.
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Affiliation(s)
- Pierre-Marc Frédérick
- Oncology Division, CHU de Québec—Université Laval Research Center, Québec, QC G1R 3S3, Canada
- Université Laval Cancer Research Centre, Québec, QC G1R 3S3, Canada
| | - Guillaume Jannot
- Oncology Division, CHU de Québec—Université Laval Research Center, Québec, QC G1R 3S3, Canada
- Université Laval Cancer Research Centre, Québec, QC G1R 3S3, Canada
| | - Isabelle Banville
- Oncology Division, CHU de Québec—Université Laval Research Center, Québec, QC G1R 3S3, Canada
- Université Laval Cancer Research Centre, Québec, QC G1R 3S3, Canada
| | - Martin J Simard
- Oncology Division, CHU de Québec—Université Laval Research Center, Québec, QC G1R 3S3, Canada
- Université Laval Cancer Research Centre, Québec, QC G1R 3S3, Canada
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2
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Pal A, Vasudevan V, Houle F, Lantin M, Maniates K, Huberdeau MQ, Abbott A, Simard M. Defining the contribution of microRNA-specific Argonautes with slicer capability in animals. Nucleic Acids Res 2024; 52:5002-5015. [PMID: 38477356 PMCID: PMC11109967 DOI: 10.1093/nar/gkae173] [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: 01/19/2023] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
microRNAs regulate gene expression through interaction with an Argonaute protein. While some members of this protein family retain an enzymatic activity capable of cleaving RNA molecules complementary to Argonaute-bound small RNAs, the role of the slicer residues in the canonical microRNA pathway is still unclear in animals. To address this, we created Caenorhabditis elegans strains with mutated slicer residues in the endogenous ALG-1 and ALG-2, the only two slicing Argonautes essential for the miRNA pathway in this animal model. We observe that the mutation in ALG-1 and ALG-2 catalytic residues affects overall animal fitness and causes phenotypes reminiscent of miRNA defects only when grown and maintained at restrictive temperature. Furthermore, the analysis of global miRNA expression shows that the slicer residues of ALG-1 and ALG-2 contribute differentially to regulate the level of specific subsets of miRNAs in young adults. We also demonstrate that altering the catalytic tetrad of those miRNA-specific Argonautes does not result in any defect in the production of canonical miRNAs. Together, these data support that the slicer residues of miRNA-specific Argonautes contribute to maintaining levels of a set of miRNAs for optimal viability and fitness in animals particularly exposed to specific growing conditions.
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Affiliation(s)
- Anisha Pal
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
| | - Vaishnav Vasudevan
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
| | - François Houle
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
| | - Michael Lantin
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
| | - Katherine A Maniates
- Waksman Institute of Microbiology and Department of Genetics, Rutgers University, USA
| | - Miguel Quévillon Huberdeau
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
| | - Allison L Abbott
- Department of Biological Sciences, Marquette University, Milwaukee, WI 53233, USA
| | - Martin J Simard
- CHU de Québec-Université Laval Research Center (Oncology Division), Quebec City, Quebec G1R 3S3, Canada
- Université Laval Cancer Research Centre, Quebec City, Quebec G1R 3S3, Canada
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3
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Kotagama K, Grimme AL, Braviner L, Yang B, Sakhawala R, Yu G, Benner LK, Joshua-Tor L, McJunkin K. Catalytic residues of microRNA Argonautes play a modest role in microRNA star strand destabilization in C. elegans. Nucleic Acids Res 2024; 52:4985-5001. [PMID: 38471816 PMCID: PMC11109956 DOI: 10.1093/nar/gkae170] [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: 01/17/2023] [Revised: 02/22/2024] [Accepted: 02/27/2024] [Indexed: 03/14/2024] Open
Abstract
Many microRNA (miRNA)-guided Argonaute proteins can cleave RNA ('slicing'), even though miRNA-mediated target repression is generally cleavage-independent. Here we use Caenorhabditis elegans to examine the role of catalytic residues of miRNA Argonautes in organismal development. In contrast to previous work, mutations in presumed catalytic residues did not interfere with development when introduced by CRISPR. We find that unwinding and decay of miRNA star strands is weakly defective in the catalytic residue mutants, with the largest effect observed in embryos. Argonaute-Like Gene 2 (ALG-2) is more dependent on catalytic residues for unwinding than ALG-1. The miRNAs that displayed the greatest (albeit minor) dependence on catalytic residues for unwinding tend to form stable duplexes with their star strand, and in some cases, lowering duplex stability alleviates dependence on catalytic residues. While a few miRNA guide strands are reduced in the mutant background, the basis of this is unclear since changes were not dependent on EBAX-1, an effector of Target-Directed miRNA Degradation (TDMD). Overall, this work defines a role for the catalytic residues of miRNA Argonautes in star strand decay; future work should examine whether this role contributes to the selection pressure to conserve catalytic activity of miRNA Argonautes across the metazoan phylogeny.
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Affiliation(s)
- Kasuen Kotagama
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Acadia L Grimme
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
- Johns Hopkins University Department of Biology, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Leah Braviner
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Bing Yang
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Rima M Sakhawala
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
- Johns Hopkins University Department of Biology, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Guoyun Yu
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Lars Kristian Benner
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Leemor Joshua-Tor
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Katherine McJunkin
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
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4
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Montgomery BE, Knittel TL, Reed KJ, Chong MC, Isolehto IJ, Cafferty ER, Smith MJ, Sprister RA, Magelky CN, Scherman H, Ketting RF, Montgomery TA. Regulation of Microprocessor assembly and localization via Pasha's WW domain in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.23.590772. [PMID: 38712061 PMCID: PMC11071396 DOI: 10.1101/2024.04.23.590772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Primary microRNA (pri-miRNA) transcripts are processed by the Microprocessor, a protein complex that includes the ribonuclease Drosha and its RNA binding partner DGCR8/Pasha. We developed a live, whole animal, fluorescence-based sensor that reliably monitors pri-miRNA processing with high sensitivity in C. elegans. Through a forward genetic selection for alleles that desilence the sensor, we identified a mutation in the conserved G residue adjacent to the namesake W residue of Pasha's WW domain. Using genome editing we also mutated the W residue and reveal that both the G and W residue are required for dimerization of Pasha and proper assembly of the Microprocessor. Surprisingly, we find that the WW domain also facilitates nuclear localization of Pasha, which in turn promotes nuclear import or retention of Drosha. Furthermore, depletion of Pasha or Drosha causes both components of the Microprocessor to mislocalize to the cytoplasm. Thus, Pasha and Drosha mutually regulate each other's spatial expression in C. elegans.
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Affiliation(s)
| | - Thiago L. Knittel
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Kailee J. Reed
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Madeleine C. Chong
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Ida J. Isolehto
- Biology of Non-coding RNA group, Institute of Molecular Biology, Mainz, Germany
- International PhD Program on Gene Regulation, Epigenetics and Genome Stability, Mainz, Germany
| | - Erin R. Cafferty
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Margaret J. Smith
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Reese A. Sprister
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Colin N. Magelky
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Hataichanok Scherman
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Rene F. Ketting
- Biology of Non-coding RNA group, Institute of Molecular Biology, Mainz, Germany
- Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, Mainz, Germany
| | - Taiowa A. Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
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5
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Vergani-Junior CA, Moro RDP, Pinto S, De-Souza EA, Camara H, Braga DL, Tonon-da-Silva G, Knittel TL, Ruiz GP, Ludwig RG, Massirer KB, Mair WB, Mori MA. An Intricate Network Involving the Argonaute ALG-1 Modulates Organismal Resistance to Oxidative Stress. Nat Commun 2024; 15:3070. [PMID: 38594249 PMCID: PMC11003958 DOI: 10.1038/s41467-024-47306-4] [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: 08/01/2023] [Accepted: 03/24/2024] [Indexed: 04/11/2024] Open
Abstract
Cellular response to redox imbalance is crucial for organismal health. microRNAs are implicated in stress responses. ALG-1, the C. elegans ortholog of human AGO2, plays an essential role in microRNA processing and function. Here we investigated the mechanisms governing ALG-1 expression in C. elegans and the players controlling lifespan and stress resistance downstream of ALG-1. We show that upregulation of ALG-1 is a shared feature in conditions linked to increased longevity (e.g., germline-deficient glp-1 mutants). ALG-1 knockdown reduces lifespan and oxidative stress resistance, while overexpression enhances survival against pro-oxidant agents but not heat or reductive stress. R02D3.7 represses alg-1 expression, impacting oxidative stress resistance at least in part via ALG-1. microRNAs upregulated in glp-1 mutants (miR-87-3p, miR-230-3p, and miR-235-3p) can target genes in the protein disulfide isomerase pathway and protect against oxidative stress. This study unveils a tightly regulated network involving transcription factors and microRNAs which controls organisms' ability to withstand oxidative stress.
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Affiliation(s)
- Carlos A Vergani-Junior
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Raíssa De P Moro
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Silas Pinto
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Evandro A De-Souza
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Henrique Camara
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Section on Integrative Physiology & Metabolism, Joslin Diabetes Center, Boston, MA, USA
| | - Deisi L Braga
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Guilherme Tonon-da-Silva
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Thiago L Knittel
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Gabriel P Ruiz
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Raissa G Ludwig
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Katlin B Massirer
- Center for Molecular Biology and Genetic Engineering (CBMEG), Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
- Center of Medicinal Chemistry (CQMED), Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - William B Mair
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Marcelo A Mori
- Department of Biochemistry and Tissue Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.
- Program in Genetics and Molecular Biology, Institute of Biology, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.
- Obesity and Comorbidities Research Center (OCRC), Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.
- Experimental Medicine Research Cluster (EMRC), Universidade Estadual de Campinas, Campinas, São Paulo, Brazil.
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6
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Kotagama K, McJunkin K. Recent advances in understanding microRNA function and regulation in C. elegans. Semin Cell Dev Biol 2024; 154:4-13. [PMID: 37055330 PMCID: PMC10564972 DOI: 10.1016/j.semcdb.2023.03.011] [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: 01/30/2023] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 04/15/2023]
Abstract
MicroRNAs (miRNAs) were first discovered in C. elegans as essential post-transcriptional regulators of gene expression. Since their initial discovery, miRNAs have been implicated in numerous areas of physiology and disease in all animals examined. In recent years, the C. elegans model continues to contribute important advances to all areas of miRNA research. Technological advances in tissue-specific miRNA profiling and genome editing have driven breakthroughs in understanding biological functions of miRNAs, mechanism of miRNA action, and regulation of miRNAs. In this review, we highlight these new C. elegans findings from the past five to seven years.
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Affiliation(s)
- Kasuen Kotagama
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases Intramural Research Program, Bethesda, MD 20892, USA
| | - Katherine McJunkin
- Laboratory of Cellular and Developmental Biology, National Institute of Diabetes and Digestive and Kidney Diseases Intramural Research Program, Bethesda, MD 20892, USA.
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7
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Pal A, Vasudevan V, Houle F, Lantin M, Maniates KA, Quevillon Huberdeau M, Abbott A, Simard MJ. Defining the contribution of microRNA-specific slicing Argonautes in animals. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.19.524781. [PMID: 36711744 PMCID: PMC9882343 DOI: 10.1101/2023.01.19.524781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
microRNAs regulate gene expression through interaction with an Argonaute protein family member. While some members of this protein family retain an enzymatic activity capable of cleaving RNA molecules complementary to Argonaute-bound small RNAs, the role of the slicing activity in the canonical microRNA pathway is still unclear in animals. To address the importance of slicing Argonautes in animals, we created Caenorhabditis elegans strains, carrying catalytically dead endogenous ALG-1 and ALG-2, the only two slicing Argonautes essential for the miRNA pathway in this animal model. We observe that the loss of ALG-1 and ALG-2 slicing activity affects overall animal fitness and causes phenotypes, reminiscent of miRNA defects, only when grown and maintained at restrictive temperature. Furthermore, the analysis of global miRNA expression shows that the catalytic activity of ALG-1 and ALG-2 differentially regulate the level of specific subsets of miRNAs in young adults. We also demonstrate that altering the slicing activity of those miRNA-specific Argonautes does not result in any defect in the production of canonical miRNAs. Together, these data support that the slicing activity of miRNA-specific Argonautes function to maintain the levels of a set of miRNAs for optimal viability and fitness in animals particularly exposed to specific growing conditions.
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8
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Kotagama K, Grimme AL, Braviner L, Yang B, Sakhawala RM, Yu G, Benner LK, Joshua-Tor L, McJunkin K. The catalytic activity of microRNA Argonautes plays a modest role in microRNA star strand destabilization in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.01.19.524782. [PMID: 36711716 PMCID: PMC9882359 DOI: 10.1101/2023.01.19.524782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Many Argonaute proteins can cleave RNA ("slicing") as part of the microRNA-induced silencing complex (miRISC), even though miRNA-mediated target repression is generally independent of target cleavage. Here we use genome editing in C. elegans to examine the role of miRNA-guided slicing in organismal development. In contrast to previous work, slicing-inactivating mutations did not interfere with normal development when introduced by CRISPR. We find that unwinding and decay of miRNA star strands is weakly defective in the absence of slicing, with the largest effect observed in embryos. Argonaute-Like Gene 2 (ALG-2) is more dependent on slicing for unwinding than ALG-1. The miRNAs that displayed the greatest (albeit minor) dependence on slicing for unwinding tend to form stable duplexes with their star strand, and in some cases, lowering duplex stability alleviates dependence on slicing. Gene expression changes were consistent with negligible to moderate loss of function for miRNA guides whose star strand was upregulated, suggesting a reduced proportion of mature miRISC in slicing mutants. While a few miRNA guide strands are reduced in the mutant background, the basis of this is unclear since changes were not dependent on EBAX-1, a factor in the Target-Directed miRNA Degradation (TDMD) pathway. Overall, this work defines a role for miRNA Argonaute slicing in star strand decay; future work should examine whether this role could have contributed to the selection pressure to conserve catalytic activity of miRNA Argonautes across the metazoan phylogeny.
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Affiliation(s)
- Kasuen Kotagama
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Acadia L. Grimme
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
- Johns Hopkins University Department of Biology, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Leah Braviner
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Bing Yang
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Rima M. Sakhawala
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
- Johns Hopkins University Department of Biology, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Guoyun Yu
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
| | - Lars Kristian Benner
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
- Current address: Johns Hopkins University Department of Biology, 3400 N. Charles Street, Baltimore, MD 21218, USA
| | - Leemor Joshua-Tor
- Cold Spring Harbor Laboratory, One Bungtown Road, Cold Spring Harbor, NY 11724, USA
| | - Katherine McJunkin
- Laboratory of Cellular and Developmental Biology, NIDDK Intramural Research Program, 50 South Drive, Bethesda, MD 20892, USA
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9
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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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10
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Uebel CJ, Rajeev S, Phillips CM. Caenorhabditis elegans germ granules are present in distinct configurations and assemble in a hierarchical manner. Development 2023; 150:dev202284. [PMID: 38009921 PMCID: PMC10753583 DOI: 10.1242/dev.202284] [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: 08/23/2023] [Accepted: 11/17/2023] [Indexed: 11/29/2023]
Abstract
RNA silencing pathways are complex, highly conserved, and perform crucial regulatory roles. In Caenorhabditis elegans germlines, RNA surveillance occurs through a series of perinuclear germ granule compartments - P granules, Z granules, SIMR foci, and Mutator foci - multiple of which form via phase separation. Although the functions of individual germ granule proteins have been extensively studied, the relationships between germ granule compartments (collectively, 'nuage') are less understood. We find that key germ granule proteins assemble into separate but adjacent condensates, and that boundaries between germ granule compartments re-establish after perturbation. We discover a toroidal P granule morphology, which encircles the other germ granule compartments in a consistent exterior-to-interior spatial organization, providing broad implications for the trajectory of an RNA as it exits the nucleus. Moreover, we quantify the stoichiometric relationships between germ granule compartments and RNA to reveal discrete populations of nuage that assemble in a hierarchical manner and differentially associate with RNAi-targeted transcripts, possibly suggesting functional differences between nuage configurations. Our work creates a more accurate model of C. elegans nuage and informs the conceptualization of RNA silencing through the germ granule compartments.
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Affiliation(s)
- Celja J. Uebel
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Sanjana Rajeev
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Carolyn M. Phillips
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
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11
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Verbeeren J, Teixeira J, Garcia SMDA. The Muscleblind-like protein MBL-1 regulates microRNA expression in Caenorhabditis elegans through an evolutionarily conserved autoregulatory mechanism. PLoS Genet 2023; 19:e1011109. [PMID: 38134228 PMCID: PMC10773944 DOI: 10.1371/journal.pgen.1011109] [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: 06/16/2023] [Revised: 01/08/2024] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
The Muscleblind-like (MBNL) family is a highly conserved set of RNA-binding proteins (RBPs) that regulate RNA metabolism during the differentiation of various animal tissues. Functional insufficiency of MBNL affects muscle and central nervous system development, and contributes to the myotonic dystrophies (DM), a set of incurable multisystemic disorders. Studies on the regulation of MBNL genes are essential to provide insight into the gene regulatory networks controlled by MBNL proteins and to understand how dysregulation within these networks causes disease. In this study, we demonstrate the evolutionary conservation of an autoregulatory mechanism that governs the function of MBNL proteins by generating two distinct protein isoform types through alternative splicing. Our aim was to further our understanding of the regulatory principles that underlie this conserved feedback loop in a whole-organismal context, and to address the biological significance of the respective isoforms. Using an alternative splicing reporter, our studies show that, during development of the Caenorhabditis elegans central nervous system, the orthologous mbl-1 gene shifts production from long protein isoforms that localize to the nucleus to short isoforms that also localize to the cytoplasm. Using isoform-specific CRISPR/Cas9-generated strains, we showed that expression of short MBL-1 protein isoforms is required for healthy neuromuscular function and neurodevelopment, while expression of long MBL-1 protein isoforms is dispensable, emphasizing a key role for cytoplasmic functionalities of the MBL-1 protein. Furthermore, RNA-seq and lifespan analyses indicated that short MBL-1 isoforms are crucial regulators of miRNA expression and, in consequence, required for normal lifespan. In conclusion, this study provides support for the disruption of cytoplasmic RNA metabolism as a contributor in myotonic dystrophy and paves the way for further exploration of miRNA regulation through MBNL proteins during development and in disease models.
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Affiliation(s)
- Jens Verbeeren
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
| | - Joana Teixeira
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
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12
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Shah VN, Neumeier J, Huberdeau MQ, Zeitler DM, Bruckmann A, Meister G, Simard MJ. Casein kinase 1 and 2 phosphorylate Argonaute proteins to regulate miRNA-mediated gene silencing. EMBO Rep 2023; 24:e57250. [PMID: 37712432 PMCID: PMC10626430 DOI: 10.15252/embr.202357250] [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: 03/30/2023] [Revised: 08/18/2023] [Accepted: 09/01/2023] [Indexed: 09/16/2023] Open
Abstract
MicroRNAs (miRNAs) together with Argonaute (AGO) proteins form the core of the RNA-induced silencing complex (RISC) to regulate gene expression of their target RNAs post-transcriptionally. Argonaute proteins are subjected to intensive regulation via various post-translational modifications that can affect their stability, silencing efficacy and specificity for targeted gene regulation. We report here that in Caenorhabditis elegans, two conserved serine/threonine kinases - casein kinase 1 alpha 1 (CK1A1) and casein kinase 2 (CK2) - regulate a highly conserved phosphorylation cluster of 4 Serine residues (S988:S998) on the miRNA-specific AGO protein ALG-1. We show that CK1A1 phosphorylates ALG-1 at sites S992 and S995, while CK2 phosphorylates ALG-1 at sites S988 and S998. Furthermore, we demonstrate that phospho-mimicking mutants of the entire S988:S998 cluster rescue the various developmental defects observed upon depleting CK1A1 and CK2. In humans, we show that CK1A1 also acts as a priming kinase of this cluster on AGO2. Altogether, our data suggest that phosphorylation of AGO within the cluster by CK1A1 and CK2 is required for efficient miRISC-target RNA binding and silencing.
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Affiliation(s)
- Vivek Nilesh Shah
- CHU de Québec‐Université Laval Research Center (Oncology Division)Quebec CityQuebecCanada
- Université Laval Cancer Research CentreQuebec CityQuebecCanada
| | - Julia Neumeier
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA BiologyUniversity of RegensburgRegensburgGermany
| | - Miguel Quévillon Huberdeau
- CHU de Québec‐Université Laval Research Center (Oncology Division)Quebec CityQuebecCanada
- Université Laval Cancer Research CentreQuebec CityQuebecCanada
| | - Daniela M Zeitler
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA BiologyUniversity of RegensburgRegensburgGermany
| | - Astrid Bruckmann
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA BiologyUniversity of RegensburgRegensburgGermany
| | - Gunter Meister
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA BiologyUniversity of RegensburgRegensburgGermany
| | - Martin J Simard
- CHU de Québec‐Université Laval Research Center (Oncology Division)Quebec CityQuebecCanada
- Université Laval Cancer Research CentreQuebec CityQuebecCanada
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13
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Lu L, Abbott AL. Male gonad-enriched microRNAs function to control sperm production in C. elegans. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.10.561762. [PMID: 37873419 PMCID: PMC10592766 DOI: 10.1101/2023.10.10.561762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Germ cell development and gamete production in animals require small RNA pathways. While studies indicate that microRNAs (miRNAs) are necessary for normal sperm production and function, the specific roles for individual miRNAs are largely unknown. Here, we use small RNA sequencing of dissected gonads and functional analysis of new loss of function alleles to identify functions for miRNAs in the control of fecundity and sperm production in Caenorhabditis elegans males and hermaphrodites. We describe a set of 29 male gonad-enriched miRNAs and identify a set of 3 individual miRNAs (mir-58.1, mir-83, and mir-235) and a miRNA cluster (mir-4807-4810.1) that are required for optimal sperm production at 20°C and 5 additional miRNAs (mir-49, mir-57, mir-261, and mir-357/358) that are required for sperm production at 25°C. We observed defects in meiotic progression in mir-58.1, mir-83, mir-235, and mir-4807-4810.1 mutants that may contribute to the reduced number of sperm. Further, analysis of multiple mutants of these miRNAs suggested complex genetic interactions between these miRNAs for sperm production. This study provides insights on the regulatory roles of miRNAs that promote optimal sperm production and fecundity in males and hermaphrodites.
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Affiliation(s)
- Lu Lu
- Department of Biological Sciences, Marquette University, Milwaukee, WI, 53201 USA
| | - Allison L. Abbott
- Department of Biological Sciences, Marquette University, Milwaukee, WI, 53201 USA
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14
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Liu L, Wang X, Zhao W, Li Q, Li J, Chen H, Shan G. Systematic characterization of small RNAs associated with C. elegans Argonautes. SCIENCE CHINA. LIFE SCIENCES 2023:10.1007/s11427-022-2304-8. [PMID: 37154856 DOI: 10.1007/s11427-022-2304-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 12/28/2022] [Indexed: 05/10/2023]
Abstract
Argonaute proteins generally play regulatory roles by forming complexes with the corresponding small RNAs (sRNAs). An expanded Argonaute family with 20 potentially functional members has been identified in Caenorhabditis elegans. Canonical sRNAs in C. elegans are miRNAs, small interfering RNAs including 22G-RNAs and 26G-RNAs, and 21U-RNAs, which are C. elegans piRNAs. Previous studies have only covered some of these Argonautes for their sRNA partners, and thus, a systematic study is needed to reveal the comprehensive regulatory networks formed by C. elegans Argonautes and their associated sRNAs. We obtained in situ knockin (KI) strains of all C. elegans Argonautes with fusion tags by CRISPR/Cas9 technology. RNA immunoprecipitation against these endogenously expressed Argonautes and high-throughput sequencing acquired the sRNA profiles of individual Argonautes. The sRNA partners for each Argonaute were then analyzed. We found that there were 10 Argonautes enriched miRNAs, 17 Argonautes bound to 22G-RNAs, 8 Argonautes bound to 26G-RNAs, and 1 Argonaute PRG-1 bound to piRNAs. Uridylated 22G-RNAs were bound by four Argonautes HRDE-1, WAGO-4, CSR-1, and PPW-2. We found that all four Argonautes played a role in transgenerational epigenetic inheritance. Regulatory roles of the corresponding Argonaute-sRNA complex in managing levels of long transcripts and interspecies regulation were also demonstrated. In this study, we portrayed the sRNAs bound to each functional Argonaute in C. elegans. Bioinformatics analyses together with experimental investigations provided perceptions in the overall view of the regulatory network formed by C. elegans Argonautes and sRNAs. The sRNA profiles bound to individual Argonautes reported here will be valuable resources for further studies.
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Affiliation(s)
- Lei Liu
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Xiaolin Wang
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China.
| | - Wenfang Zhao
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Qiqi Li
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - Jingxin Li
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China
| | - He Chen
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Anhui University, Hefei, 230601, China
| | - Ge Shan
- Department of Laboratory Medicine, The First Affiliated Hospital of USTC, the CAS Key Laboratory of Innate Immunity and Chronic Disease, School of Basic Medical Sciences, Division of Life Science and Medicine, University of Science and Technology of China, Hefei, 230027, China.
- Department of Pulmonary and Critical Care Medicine, Regional Medical Center for National Institute of Respiratory Diseases, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, 310016, China.
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15
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Cubillas C, Sandoval Del Prado LE, Goldacker S, Fujii C, Pinski AN, Zielke J, Wang D. The alg-1 Gene Is Necessary for Orsay Virus Replication in Caenorhabditis elegans. J Virol 2023; 97:e0006523. [PMID: 37017532 PMCID: PMC10134801 DOI: 10.1128/jvi.00065-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/10/2023] [Indexed: 04/06/2023] Open
Abstract
The establishment of the Orsay virus-Caenorhabditis elegans infection model has enabled the identification of host factors essential for virus infection. Argonautes are RNA interacting proteins evolutionary conserved in the three domains of life that are key components of small RNA pathways. C. elegans encodes 27 argonautes or argonaute-like proteins. Here, we determined that mutation of the argonaute-like gene 1, alg-1, results in a greater than 10,000-fold reduction in Orsay viral RNA levels, which could be rescued by ectopic expression of alg-1. Mutation in ain-1, a known interactor of ALG-1 and component of the RNA-induced silencing complex, also resulted in a significant reduction in Orsay virus levels. Viral RNA replication from an endogenous transgene replicon system was impaired by the lack of ALG-1, suggesting that ALG-1 plays a role during the replication stage of the virus life cycle. Orsay virus RNA levels were unaffected by mutations in the ALG-1 RNase H-like motif that ablate the slicer activity of ALG-1. These findings demonstrate a novel function of ALG-1 in promoting Orsay virus replication in C. elegans. IMPORTANCE All viruses are obligate intracellular parasites that recruit the cellular machinery of the host they infect to support their own proliferation. We used Caenorhabditis elegans and its only known infecting virus, Orsay virus, to identify host proteins relevant for virus infection. We determined that ALG-1, a protein previously known to be important in influencing worm life span and the expression levels of thousands of genes, is required for Orsay virus infection of C. elegans. This is a new function attributed to ALG-1 that was not recognized before. In humans, it has been shown that AGO2, a close relative protein to ALG-1, is essential for hepatitis C virus replication. This demonstrates that through evolution from worms to humans, some proteins have maintained similar functions, and consequently, this suggests that studying virus infection in a simple worm model has the potential to provide novel insights into strategies used by viruses to proliferate.
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Affiliation(s)
- Ciro Cubillas
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Luis Enrique Sandoval Del Prado
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Sydney Goldacker
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Chika Fujii
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Amanda N. Pinski
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Jon Zielke
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
| | - David Wang
- Department of Molecular Microbiology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Pathology & Immunology, School of Medicine, Washington University in St. Louis, St. Louis, Missouri, USA
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16
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Nguyen TL, Nguyen TD, Ngo MK, Nguyen TA. Dissection of the Caenorhabditis elegans Microprocessor. Nucleic Acids Res 2023; 51:1512-1527. [PMID: 36598924 PMCID: PMC9976908 DOI: 10.1093/nar/gkac1170] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/17/2022] [Accepted: 11/25/2022] [Indexed: 01/05/2023] Open
Abstract
Microprocessor (MP) is a complex involved in initiating the biogenesis of microRNAs (miRNAs) by cleaving primary microRNAs (pri-miRNAs). miRNAs are small single-stranded RNAs that play a key role in the post-transcriptional regulation of gene expression. Thus, understanding the molecular mechanism of MP is critical for interpreting the roles of miRNAs in normal cellular processes and during the onset of various diseases. MP comprises a ribonuclease enzyme, DROSHA, and a dimeric RNA-binding protein, which is called DGCR8 in humans and Pasha in Caenorhabditis elegans. DROSHA cleaves stem-loop structures located within pri-miRNAs to generate pre-miRNAs. Although the molecular mechanism of human MP (hMP; hDROSHA-DGCR8) is well understood, that of Caenorhabditis elegans MP (cMP; cDrosha-Pasha) is still largely unknown. Here, we reveal the molecular mechanism of cMP and show that it is distinct from that of hMP. We demonstrate that cDrosha and Pasha measure ∼16 and ∼25 bp along a pri-miRNA stem, respectively, and they work together to determine the site of cMP cleavage in pri-miRNAs. We also demonstrate the molecular basis for their substrate measurement. Thus, our findings reveal a previously unknown molecular mechanism of cMP; demonstrate the differences between the mechanisms of hMP and cMP; and provide a foundation for revealing the mechanisms regulating miRNA expression in different animal species.
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Affiliation(s)
- Thuy Linh Nguyen
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Trung Duc Nguyen
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Minh Khoa Ngo
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
| | - Tuan Anh Nguyen
- Division of Life Science, The Hong Kong University of Science & Technology, Hong Kong, China
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17
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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: 21] [Impact Index Per Article: 21.0] [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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18
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Liontis T, Verma K, Grishok A. DOT-1.1 (DOT1L) deficiency in C. elegans leads to small RNA-dependent gene activation. BBA ADVANCES 2023; 3:100080. [PMID: 37082252 PMCID: PMC10074844 DOI: 10.1016/j.bbadva.2023.100080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/27/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023] Open
Abstract
Methylation of histone H3 at lysine 79 (H3K79) is conserved from yeast to humans and is accomplished by Dot1 (disruptor of telomeric silencing-1) methyltransferases. The C. elegans enzyme DOT-1.1 and its interacting partners are similar to the mammalian DOT1L (Dot1-like) complex. The C. elegans DOT-1.1 complex has been functionally connected to RNA interference. Specifically, we have previously shown that embryonic and larval lethality of dot-1.1 mutant worms deficient in H3K79 methylation was suppressed by mutations in the RNAi pathway genes responsible for generation (rde-4) and function (rde-1) of primary small interfering RNAs (siRNAs). This suggests that dot-1.1 mutant lethality is dependent on the enhanced production of some siRNAs. We have also found that this lethality is suppressed by a loss-of-function of CED-3, a conserved apoptotic protease. Here, we describe a comparison of gene expression and primary siRNA production changes between control and dot-1.1 deletion mutant embryos. We found that elevated antisense siRNA production occurred more often at upregulated than downregulated genes. Importantly, gene expression changes were dependent on RDE-4 in both instances. Moreover, the upregulated group, which is potentially activated by ectopic siRNAs, was enriched in protease-coding genes. Our findings are consistent with a model where in the absence of H3K79 methylation there is a small RNA-dependent activation of protease genes, which leads to embryonic and larval lethality. DOT1 enzymes' conservation suggests that the interplay between H3K79 methylation and small RNA pathways may exist in higher organisms.
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19
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Albarqi MMY, Ryder SP. The role of RNA-binding proteins in orchestrating germline development in Caenorhabditis elegans. Front Cell Dev Biol 2023; 10:1094295. [PMID: 36684428 PMCID: PMC9846511 DOI: 10.3389/fcell.2022.1094295] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/19/2022] [Indexed: 01/06/2023] Open
Abstract
RNA passed from parents to progeny controls several aspects of early development. The germline of the free-living nematode Caenorhabditis elegans contains many families of evolutionarily conserved RNA-binding proteins (RBPs) that target the untranslated regions of mRNA transcripts to regulate their translation and stability. In this review, we summarize what is known about the binding specificity of C. elegans germline RNA-binding proteins and the mechanisms of mRNA regulation that contribute to their function. We examine the emerging role of miRNAs in translational regulation of germline and embryo development. We also provide an overview of current technology that can be used to address the gaps in our understanding of RBP regulation of mRNAs. Finally, we present a hypothetical model wherein multiple 3'UTR-mediated regulatory processes contribute to pattern formation in the germline to ensure the proper and timely localization of germline proteins and thus a functional reproductive system.
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20
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Quévillon Huberdeau M, Shah VN, Nahar S, Neumeier J, Houle F, Bruckmann A, Gypas F, Nakanishi K, Großhans H, Meister G, Simard MJ. A specific type of Argonaute phosphorylation regulates binding to microRNAs during C. elegans development. Cell Rep 2022; 41:111822. [PMID: 36516777 PMCID: PMC10436268 DOI: 10.1016/j.celrep.2022.111822] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 09/22/2022] [Accepted: 11/21/2022] [Indexed: 12/15/2022] Open
Abstract
Argonaute proteins are at the core of the microRNA-mediated gene silencing pathway essential for animals. In C. elegans, the microRNA-specific Argonautes ALG-1 and ALG-2 regulate multiple processes required for proper animal developmental timing and viability. Here we identified a phosphorylation site on ALG-1 that modulates microRNA association. Mutating ALG-1 serine 642 into a phospho-mimicking residue impairs microRNA binding and causes embryonic lethality and post-embryonic phenotypes that are consistent with alteration of microRNA functions. Monitoring microRNA levels in alg-1 phosphorylation mutant animals shows that microRNA passenger strands increase in abundance but are not preferentially loaded into ALG-1, indicating that the miRNA binding defects could lead to microRNA duplex accumulation. Our genetic and biochemical experiments support protein kinase A (PKA) KIN-1 as the putative kinase that phosphorylates ALG-1 serine 642. Our data indicate that PKA triggers ALG-1 phosphorylation to regulate its microRNA association during C. elegans development.
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Affiliation(s)
- Miguel Quévillon Huberdeau
- CHU de Québec-Université Laval Research Center (Oncology Division), Québec City, QC G1R 3S3, Canada; Université Laval Cancer Research Centre, Québec City, QC G1R 3S3, Canada
| | - Vivek Nilesh Shah
- CHU de Québec-Université Laval Research Center (Oncology Division), Québec City, QC G1R 3S3, Canada; Université Laval Cancer Research Centre, Québec City, QC G1R 3S3, Canada
| | - Smita Nahar
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Julia Neumeier
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA Biology, University of Regensburg, 93053 Regensburg, Germany
| | - François Houle
- CHU de Québec-Université Laval Research Center (Oncology Division), Québec City, QC G1R 3S3, Canada; Université Laval Cancer Research Centre, Québec City, QC G1R 3S3, Canada
| | - Astrid Bruckmann
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA Biology, University of Regensburg, 93053 Regensburg, Germany
| | - Foivos Gypas
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Kotaro Nakanishi
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; Center for RNA Biology, Columbus, OH 43210, USA
| | - Helge Großhans
- Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland; University of Basel, 4056 Basel, Switzerland
| | - Gunter Meister
- Regensburg Center for Biochemistry (RCB), Laboratory for RNA Biology, University of Regensburg, 93053 Regensburg, Germany
| | - Martin J Simard
- CHU de Québec-Université Laval Research Center (Oncology Division), Québec City, QC G1R 3S3, Canada; Université Laval Cancer Research Centre, Québec City, QC G1R 3S3, Canada.
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21
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Brenner JL, Jyo EM, Mohammad A, Fox P, Jones V, Mardis E, Schedl T, Maine EM. TRIM-NHL protein, NHL-2, modulates cell fate choices in the C. elegans germ line. Dev Biol 2022; 491:43-55. [PMID: 36063869 PMCID: PMC9922029 DOI: 10.1016/j.ydbio.2022.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/19/2022] [Accepted: 08/27/2022] [Indexed: 12/01/2022]
Abstract
Many tissues contain multipotent stem cells that are critical for maintaining tissue function. In Caenorhabditis elegans, germline stem cells allow gamete production to continue in adulthood. In the gonad, GLP-1/Notch signaling from the distal tip cell niche to neighboring germ cells activates a complex regulatory network to maintain a stem cell population. GLP-1/Notch signaling positively regulates production of LST-1 and SYGL-1 proteins that, in turn, interact with a set of PUF/FBF proteins to positively regulate the stem cell fate. We previously described sog (suppressor of glp-1 loss of function) and teg (tumorous enhancer of glp-1 gain of function) genes that limit the stem cell fate and/or promote the meiotic fate. Here, we show that sog-10 is allelic to nhl-2. NHL-2 is a member of the conserved TRIM-NHL protein family whose members can bind RNA and ubiquitinate protein substrates. We show that NHL-2 acts, at least in part, by inhibiting the expression of PUF-3 and PUF-11 translational repressor proteins that promote the stem cell fate. Two other negative regulators of stem cell fate, CGH-1 (conserved germline helicase) and ALG-5 (Argonaute protein), may work with NHL-2 to modulate the stem cell population. In addition, NHL-2 activity promotes the male germ cell fate in XX animals.
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Affiliation(s)
- John L Brenner
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Erin M Jyo
- Department of Biology, Syracuse University, Syracuse, NY, 13210, USA
| | - Ariz Mohammad
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Paul Fox
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Vovanti Jones
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Elaine Mardis
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Tim Schedl
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, 63110, USA.
| | - Eleanor M Maine
- Department of Biology, Syracuse University, Syracuse, NY, 13210, USA.
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22
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Phillips CM, Updike DL. Germ granules and gene regulation in the Caenorhabditis elegans germline. Genetics 2022; 220:6541922. [PMID: 35239965 PMCID: PMC8893257 DOI: 10.1093/genetics/iyab195] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 10/10/2021] [Indexed: 01/27/2023] Open
Abstract
The transparency of Caenorhabditis elegans provides a unique window to observe and study the function of germ granules. Germ granules are specialized ribonucleoprotein (RNP) assemblies specific to the germline cytoplasm, and they are largely conserved across Metazoa. Within the germline cytoplasm, they are positioned to regulate mRNA abundance, translation, small RNA production, and cytoplasmic inheritance to help specify and maintain germline identity across generations. Here we provide an overview of germ granules and focus on the significance of more recent observations that describe how they further demix into sub-granules, each with unique compositions and functions.
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Affiliation(s)
- Carolyn M Phillips
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA,Corresponding author: (C.M.P.); (D.L.U.)
| | - Dustin L Updike
- The Mount Desert Island Biological Laboratory, Bar Harbor, ME 04672, USA,Corresponding author: (C.M.P.); (D.L.U.)
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23
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Toker IA, Lev I, Mor Y, Gurevich Y, Fisher D, Houri-Zeevi L, Antonova O, Doron H, Anava S, Gingold H, Hadany L, Shaham S, Rechavi O. Transgenerational inheritance of sexual attractiveness via small RNAs enhances evolvability in C. elegans. Dev Cell 2022; 57:298-309.e9. [PMID: 35134343 PMCID: PMC8826646 DOI: 10.1016/j.devcel.2022.01.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 09/12/2021] [Accepted: 01/05/2022] [Indexed: 11/16/2022]
Abstract
It is unknown whether transient transgenerational epigenetic responses to environmental challenges affect the process of evolution, which typically unfolds over many generations. Here, we show that in C. elegans, inherited small RNAs control genetic variation by regulating the crucial decision of whether to self-fertilize or outcross. We found that under stressful temperatures, younger hermaphrodites secrete a male-attracting pheromone. Attractiveness transmits transgenerationally to unstressed progeny via heritable small RNAs and the Argonaute Heritable RNAi Deficient-1 (HRDE-1). We identified an endogenous small interfering RNA pathway, enriched in endo-siRNAs that target sperm genes, that transgenerationally regulates sexual attraction, male prevalence, and outcrossing rates. Multigenerational mating competition experiments and mathematical simulations revealed that over generations, animals that inherit attractiveness mate more and their alleles spread in the population. We propose that the sperm serves as a "stress-sensor" that, via small RNA inheritance, promotes outcrossing in challenging environments when increasing genetic variation is advantageous.
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Affiliation(s)
- Itai Antoine Toker
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
| | - Itamar Lev
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
| | - Yael Mor
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
| | - Yael Gurevich
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Doron Fisher
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Leah Houri-Zeevi
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Olga Antonova
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Hila Doron
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Sarit Anava
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Hila Gingold
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Lilach Hadany
- School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Shai Shaham
- Laboratory of Developmental Genetics, The Rockefeller University, New York, NY, USA
| | - Oded Rechavi
- Department of Neurobiology, Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
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24
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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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25
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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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26
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Frédérick PM, Simard MJ. Regulation and different functions of the animal microRNA-induced silencing complex. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1701. [PMID: 34725940 DOI: 10.1002/wrna.1701] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 01/03/2023]
Abstract
Among the different types of small RNAs, microRNAs (miRNAs) are key players in controlling gene expression at the mRNA level. To be active, they must associate with an Argonaute protein to form the miRNA induced silencing complex (miRISC) and binds to specific mRNA through complementarity sequences. The miRISC binding to an mRNA can lead to multiple outcomes, the most frequent being inhibition of the translation and/or deadenylation followed by decapping and mRNA decay. In the last years, several studies described different mechanisms modulating miRISC functions in animals. For instance, the regulation of the Argonaute protein through post-translational modifications can change the miRISC gene regulatory activity as well as modulate its binding to proteins, mRNA targets and miRISC stability. Furthermore, the presence of RNA binding proteins and multiple miRISCs at the targeted mRNA 3' untranslated region (3'UTR) can also affect its function through cooperation or competition mechanisms, underlying the importance of the 3'UTR environment in miRNA-mediated repression. Another way to regulate the miRISC function is by modulation of its interactors, forming different types of miRNA silencing complexes that affect gene regulation differently. It is also reported that the subcellular localization of several components of the miRNA pathway can modulate miRISC function, suggesting an important role for vesicular trafficking in the regulation of this essential silencing complex. This article is categorized under: RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action Regulatory RNAs/RNAi/Riboswitches > Biogenesis of Effector Small RNAs.
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Affiliation(s)
- Pierre-Marc Frédérick
- Oncology Division, CHU de Québec-Université Laval Research Center, Québec, QC, Canada.,Université Laval Cancer Research Centre, Québec, QC, Canada
| | - Martin J Simard
- Oncology Division, CHU de Québec-Université Laval Research Center, Québec, QC, Canada.,Université Laval Cancer Research Centre, Québec, QC, Canada
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27
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Pagliuso DC, Bodas DM, Pasquinelli AE. Recovery from heat shock requires the microRNA pathway in Caenorhabditis elegans. PLoS Genet 2021; 17:e1009734. [PMID: 34351906 PMCID: PMC8370650 DOI: 10.1371/journal.pgen.1009734] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 08/17/2021] [Accepted: 07/22/2021] [Indexed: 12/16/2022] Open
Abstract
The heat shock response (HSR) is a highly conserved cellular process that promotes survival during stress. A hallmark of the HSR is the rapid induction of heat shock proteins (HSPs), such as HSP-70, by transcriptional activation. Once the stress is alleviated, HSPs return to near basal levels through incompletely understood mechanisms. Here, we show that the microRNA pathway acts during heat shock recovery in Caenorhabditis elegans. Depletion of the miRNA Argonaute, Argonaute Like Gene 1 (ALG-1), after an episode of heat shock resulted in decreased survival and perdurance of high hsp-70 levels. We present evidence that regulation of hsp-70 is dependent on miR-85 and sequences in the hsp-70 3’UTR that contain target sites for this miRNA. Regulation of hsp-70 by the miRNA pathway was found to be particularly important during recovery from HS, as animals that lacked miR-85 or its target sites in the hsp-70 3’UTR overexpressed HSP-70 and exhibited reduced viability. In summary, our findings show that down-regulation of hsp-70 by miR-85 after HS promotes survival, highlighting a previously unappreciated role for the miRNA pathway during recovery from stress. In the natural world, organisms constantly face stressful conditions such as oxidative stress, pathogen infection, starvation and heat stress. While many studies have focused on the cellular response to stress, less is known about how gene expression re-sets after the stress has been ameliorated. Here, we show that the microRNA pathway plays a critical role during the recovery phase after an episode of heat shock in the nematode, Caenorhabditis elegans. Elevated temperatures induce high expression of heat shock proteins (HSPs), including HSP-70, that provide protection from the damaging effects of high heat. We found that restoration of basal levels of HSP-70 after heat shock depends on Argonaute Like Gene 1 and miR-85. Moreover, loss of miRNA-mediated repression of HSP-70 results in compromised survival following heat shock. Our study draws attention to the recovery phase of the heat shock response and highlights an important role for the microRNA pathway in re-establishing gene expression programs needed for organismal viability post stress.
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Affiliation(s)
- Delaney C. Pagliuso
- Division of Biology, University of California, San Diego, La Jolla, California, United States of America
| | - Devavrat M. Bodas
- Division of Biology, University of California, San Diego, La Jolla, California, United States of America
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Amy E. Pasquinelli
- Division of Biology, University of California, San Diego, La Jolla, California, United States of America
- * E-mail:
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28
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Gudipati RK, Braun K, Gypas F, Hess D, Schreier J, Carl SH, Ketting RF, Großhans H. Protease-mediated processing of Argonaute proteins controls small RNA association. Mol Cell 2021; 81:2388-2402.e8. [PMID: 33852894 DOI: 10.1016/j.molcel.2021.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 12/13/2022]
Abstract
Small RNA pathways defend the germlines of animals against selfish genetic elements, yet pathway activities need to be contained to prevent silencing of self genes. Here, we reveal a proteolytic mechanism that controls endogenous small interfering (22G) RNA activity in the Caenorhabditis elegans germline to protect genome integrity and maintain fertility. We find that DPF-3, a P-granule-localized N-terminal dipeptidase orthologous to mammalian dipeptidyl peptidase (DPP) 8/9, processes the unusually proline-rich N termini of WAGO-1 and WAGO-3 Argonaute (Ago) proteins. Without DPF-3 activity, these WAGO proteins lose their proper complement of 22G RNAs. Desilencing of repeat-containing and transposon-derived transcripts, DNA damage, and acute sterility ensue. These phenotypes are recapitulated when WAGO-1 and WAGO-3 are rendered resistant to DPF-3-mediated processing, identifying them as critical substrates of DPF-3. We conclude that N-terminal processing of Ago proteins regulates their activity and promotes silencing of selfish genetic elements by ensuring Ago association with appropriate small RNAs.
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Affiliation(s)
- Rajani Kanth Gudipati
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland.
| | - Kathrin Braun
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Foivos Gypas
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Daniel Hess
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - Jan Schreier
- Biology of Non-coding RNA, Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany; International PhD Programme on Gene Regulation, Epigenetics & Genome Stability, Mainz, Germany
| | - Sarah H Carl
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland
| | - René F Ketting
- Biology of Non-coding RNA, Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany; Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University, 55099 Mainz, Germany
| | - Helge Großhans
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, Basel 4058, Switzerland; University of Basel, Petersplatz 1, 4056 Basel, Switzerland.
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29
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Brosnan CA, Palmer AJ, Zuryn S. Cell-type-specific profiling of loaded miRNAs from Caenorhabditis elegans reveals spatial and temporal flexibility in Argonaute loading. Nat Commun 2021; 12:2194. [PMID: 33850152 PMCID: PMC8044110 DOI: 10.1038/s41467-021-22503-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 03/18/2021] [Indexed: 12/13/2022] Open
Abstract
Multicellularity has coincided with the evolution of microRNAs (miRNAs), small regulatory RNAs that are integrated into cellular differentiation and homeostatic gene-regulatory networks. However, the regulatory mechanisms underpinning miRNA activity have remained largely obscured because of the precise, and thus difficult to access, cellular contexts under which they operate. To resolve these, we have generated a genome-wide map of active miRNAs in Caenorhabditis elegans by revealing cell-type-specific patterns of miRNAs loaded into Argonaute (AGO) silencing complexes. Epitope-labelled AGO proteins were selectively expressed and immunoprecipitated from three distinct tissue types and associated miRNAs sequenced. In addition to providing information on biological function, we define adaptable miRNA:AGO interactions with single-cell-type and AGO-specific resolution. We demonstrate spatial and temporal dynamicism, flexibility of miRNA loading, and suggest miRNA regulatory mechanisms via AGO selectivity in different tissues and during ageing. Additionally, we resolve widespread changes in AGO-regulated gene expression by analysing translatomes specifically in neurons.
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Affiliation(s)
- Christopher A Brosnan
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Australia.
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane, Australia.
| | - Alexander J Palmer
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | - Steven Zuryn
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Australia.
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30
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Maniates KA, Olson BS, Abbott AL. Sperm fate is promoted by the mir-44 microRNA family in the Caenorhabditis elegans hermaphrodite germline. Genetics 2021; 217:1-14. [PMID: 33683352 PMCID: PMC8045739 DOI: 10.1093/genetics/iyaa006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 11/12/2020] [Indexed: 11/12/2022] Open
Abstract
Posttranscriptional regulation of gene expression, typically effected by RNA-binding proteins, microRNAs (miRNAs), and translation initiation factors, is essential for normal germ cell function. Numerous miRNAs have been detected in the germline; however, the functions of specific miRNAs remain largely unknown. Functions of miRNAs have been difficult to determine as miRNAs often modestly repress target mRNAs and are suggested to sculpt or fine tune gene expression to allow for the robust expression of cell fates. In Caenorhabditis elegans hermaphrodites, cell fate decisions are made for germline sex determination during larval development when sperm are generated in a short window before the switch to oocyte production. Here, analysis of newly generated mir-44 family mutants has identified a family of miRNAs that modulate the germline sex determination pathway in C. elegans. Mutants with the loss of mir-44 and mir-45 produce fewer sperm, showing both a delay in the specification and formation of sperm as well as an early termination of sperm specification accompanied by a premature switch to oocyte production. mir-44 and mir-45 are necessary for the normal period of fog-1 expression in larval development. Through genetic analysis, we find that mir-44 and mir-45 may act upstream of fbf-1 and fem-3 to promote sperm specification. Our research indicates that the mir-44 family promotes sperm cell fate specification during larval development and identifies an additional posttranscriptional regulator of the germline sex determination pathway.
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Affiliation(s)
- Katherine A Maniates
- Department of Biological Sciences, Marquette University, 1428 W. Clybourn Ave, PO Box 1881, Milwaukee, WI 53233, USA
| | - Benjamin S Olson
- Department of Biological Sciences, Marquette University, 1428 W. Clybourn Ave, PO Box 1881, Milwaukee, WI 53233, USA
| | - Allison L Abbott
- Department of Biological Sciences, Marquette University, 1428 W. Clybourn Ave, PO Box 1881, Milwaukee, WI 53233, USA
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31
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Sundby AE, Molnar RI, Claycomb JM. Connecting the Dots: Linking Caenorhabditis elegans Small RNA Pathways and Germ Granules. Trends Cell Biol 2021; 31:387-401. [PMID: 33526340 DOI: 10.1016/j.tcb.2020.12.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 12/15/2022]
Abstract
Germ granules are non-membrane bound, phase-separated organelles, composed of RNAs and proteins. Germ granules are present only within the germ cells of animals, including model systems such as Caenorhabditis elegans, Drosophila, mice, and zebrafish, where they play critical roles in specifying the germ lineage, the inheritance of epigenetic information, and post-transcriptional gene regulation. Across species, conserved germ granule proteins reflect these essential functions. A significant proportion of proteins that localize to germ granules are components of RNA metabolism and small RNA (sRNA) gene regulatory pathways. Here we synthesize our current knowledge of the roles that germ granules and their components play in sRNA pathway functions, transgenerational inheritance, and fertility in the C. elegans germline.
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Affiliation(s)
- 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
| | - Julie M Claycomb
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
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32
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Lev I, Rechavi O. Germ Granules Allow Transmission of Small RNA-Based Parental Responses in the "Germ Plasm". iScience 2020; 23:101831. [PMID: 33305186 PMCID: PMC7718480 DOI: 10.1016/j.isci.2020.101831] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In the recent decade small RNA-based inheritance has been implicated in a variety of transmitted physiological responses to the environment. In Caenorhabditis elegans, heritable small RNAs rely on RNA-dependent RNA polymerases, RNA-processing machinery, chromatin modifiers, and argonauts for their biogenesis and gene-regulatory effects. Importantly, many of these factors reside in evolutionary conserved germ granules that are required for maintaining germ cell identity and gene expression. Recent literature demonstrated that transient disturbance to the stability of the germ granules leads to changes in the pools of heritable small RNAs and the physiology of the progeny. In this piece, we discuss the heritable consequences of transient destabilization of germ granules and elaborate on the various small RNA-related processes that act in the germ granules. We further propose that germ granules may serve as environment sensors that translate environmental changes to inheritable small RNA-based responses.
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Affiliation(s)
- Itamar Lev
- Department of Neurobiology, Wise Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
- Department of Neurobiology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Campus-Vienna-BioCenter 1, 1030 Vienna, Austria
| | - Oded Rechavi
- Department of Neurobiology, Wise Faculty of Life Sciences & Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel
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33
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Fridrich A, Modepalli V, Lewandowska M, Aharoni R, Moran Y. Unravelling the developmental and functional significance of an ancient Argonaute duplication. Nat Commun 2020; 11:6187. [PMID: 33273471 PMCID: PMC7713132 DOI: 10.1038/s41467-020-20003-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 10/30/2020] [Indexed: 12/28/2022] Open
Abstract
MicroRNAs (miRNAs) base-pair to messenger RNA targets and guide Argonaute proteins to mediate their silencing. This target regulation is considered crucial for animal physiology and development. However, this notion is based exclusively on studies in bilaterians, which comprise almost all lab model animals. To fill this phylogenetic gap, we characterize the functions of two Argonaute paralogs in the sea anemone Nematostella vectensis of the phylum Cnidaria, which is separated from bilaterians by ~600 million years. Using genetic manipulations, Argonaute-immunoprecipitations and high-throughput sequencing, we provide experimental evidence for the developmental importance of miRNAs in a non-bilaterian animal. Additionally, we uncover unexpected differential distribution of distinct miRNAs between the two Argonautes and the ability of one of them to load additional types of small RNAs. This enables us to postulate a novel model for evolution of miRNA precursors in sea anemones and their relatives, revealing alternative trajectories for metazoan miRNA evolution.
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Affiliation(s)
- Arie Fridrich
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - Vengamanaidu Modepalli
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
- The Marine Biological Association of the United Kingdom, Citadel Hill, Plymouth, UK
| | - Magda Lewandowska
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - Reuven Aharoni
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel
| | - Yehu Moran
- Department of Ecology, Evolution and Behavior, Alexander Silberman Institute of Life Sciences, Faculty of Science, The Hebrew University of Jerusalem, 9190401, Jerusalem, Israel.
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34
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Galagali H, Kim JK. The multifaceted roles of microRNAs in differentiation. Curr Opin Cell Biol 2020; 67:118-140. [PMID: 33152557 DOI: 10.1016/j.ceb.2020.08.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022]
Abstract
MicroRNAs (miRNAs) are major drivers of cell fate specification and differentiation. The post-transcriptional regulation of key molecular factors by microRNAs contributes to the progression of embryonic and postembryonic development in several organisms. Following the discovery of lin-4 and let-7 in Caenorhabditis elegans and bantam microRNAs in Drosophila melanogaster, microRNAs have emerged as orchestrators of cellular differentiation and developmental timing. Spatiotemporal control of microRNAs and associated protein machinery can modulate microRNA activity. Additionally, adaptive modulation of microRNA expression and function in response to changing environmental conditions ensures that robust cell fate specification during development is maintained. Herein, we review the role of microRNAs in the regulation of differentiation during development.
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Affiliation(s)
- Himani Galagali
- Department of Biology, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - John K Kim
- Department of Biology, Johns Hopkins University, Baltimore, MD, 21218, USA.
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35
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Sun Y, Yu Q, Li L, Mei Z, Zhou B, Liu S, Pan T, Wu L, Lei Y, Liu L, Drmanac R, Ma K, Liu S. Single-cell RNA profiling links ncRNAs to spatiotemporal gene expression during C. elegans embryogenesis. Sci Rep 2020; 10:18863. [PMID: 33139759 PMCID: PMC7606524 DOI: 10.1038/s41598-020-75801-3] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/06/2020] [Indexed: 01/04/2023] Open
Abstract
Recent studies show that non-coding RNAs (ncRNAs) can regulate the expression of protein-coding genes and play important roles in mammalian development. Previous studies have revealed that during C. elegans (Caenorhabditis elegans) embryo development, numerous genes in each cell are spatiotemporally regulated, causing the cell to differentiate into distinct cell types and tissues. We ask whether ncRNAs participate in the spatiotemporal regulation of genes in different types of cells and tissues during the embryogenesis of C. elegans. Here, by using marker-free full-length high-depth single-cell RNA sequencing (scRNA-seq) technique, we sequence the whole transcriptomes from 1031 embryonic cells of C. elegans and detect 20,431 protein-coding genes, including 22 cell-type-specific protein-coding markers, and 9843 ncRNAs including 11 cell-type-specific ncRNA markers. We induce a ncRNAs-based clustering strategy as a complementary strategy to the protein-coding gene-based clustering strategy for single-cell classification. We identify 94 ncRNAs that have never been reported to regulate gene expressions, are co-expressed with 1208 protein-coding genes in cell type specific and/or embryo time specific manners. Our findings suggest that these ncRNAs could potentially influence the spatiotemporal expression of the corresponding genes during the embryogenesis of C. elegans.
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Affiliation(s)
- Yan Sun
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Qichao Yu
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Lei Li
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
| | | | - Biaofeng Zhou
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Shang Liu
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Taotao Pan
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Liang Wu
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Ying Lei
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | - Longqi Liu
- BGI-Shenzhen, Shenzhen, 518083, China
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China
| | | | - Kun Ma
- BGI-Shenzhen, Shenzhen, 518083, China.
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China.
| | - Shiping Liu
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, 518083, China.
- BGI-Shenzhen, Shenzhen, 518083, China.
- Shenzhen Key Laboratory of Single-Cell Omics, BGI-Shenzhen, Shenzhen, 518100, China.
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Abstract
A diversity of gene regulatory mechanisms drives the changes in gene expression required for animal development. Here, we discuss the developmental roles of a class of gene regulatory factors composed of a core protein subunit of the Argonaute family and a 21-26-nucleotide RNA cofactor. These represent ancient regulatory complexes, originally evolved to repress genomic parasites such as transposons, viruses and retroviruses. However, over the course of evolution, small RNA-guided pathways have expanded and diversified, and they play multiple roles across all eukaryotes. Pertinent to this review, Argonaute and small RNA-mediated regulation has acquired numerous functions that affect all aspects of animal life. The regulatory function is provided by the Argonaute protein and its interactors, while the small RNA provides target specificity, guiding the Argonaute to a complementary RNA. C. elegans has 19 different, functional Argonautes, defining distinct yet interconnected pathways. Each Argonaute binds a relatively well-defined class of small RNA with distinct molecular properties. A broad classification of animal small RNA pathways distinguishes between two groups: (i) the microRNA pathway is involved in repressing relatively specific endogenous genes and (ii) the other small RNA pathways, which effectively act as a genomic immune system to primarily repress expression of foreign or "non-self" RNA while maintaining correct endogenous gene expression. microRNAs play prominent direct roles in all developmental stages, adult physiology and lifespan. The other small RNA pathways act primarily in the germline, but their impact extends far beyond, into embryogenesis and adult physiology, and even to subsequent generations. Here, we review the mechanisms and developmental functions of the diverse small RNA pathways of C. elegans.
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Affiliation(s)
| | - Luisa Cochella
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Vienna, Austria.
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37
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Svendsen JM, Reed KJ, Vijayasarathy T, Montgomery BE, Tucci RM, Brown KC, Marks TN, Nguyen DAH, Phillips CM, Montgomery TA. henn-1/HEN1 Promotes Germline Immortality in Caenorhabditis elegans. Cell Rep 2020; 29:3187-3199.e4. [PMID: 31801082 PMCID: PMC6922003 DOI: 10.1016/j.celrep.2019.10.114] [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: 03/13/2019] [Revised: 09/28/2019] [Accepted: 10/28/2019] [Indexed: 12/21/2022] Open
Abstract
The germline contains an immortal cell lineage that ensures the faithful transmission of genetic and, in some instances, epigenetic information from one generation to the next. Here, we show that in Caenorhabditis elegans, the small RNA 3′-2′-O-methyltransferase henn-1/HEN1 is required for sustained fertility across generations. In the absence of henn-1, animals become progressively less fertile, becoming sterile after ~30 generations at 25°C. Sterility in henn-1 mutants is accompanied by severe defects in germline proliferation and maintenance. The requirement for henn-1 in transgenerational fertility is likely due to its role in methylating and, thereby, stabilizing Piwi-interacting RNAs (piRNAs). However, despite being essential for piRNA stability in embryos, henn-1 is not required for piRNA stability in adults. Thus, we propose that methylation is important for the role of piRNAs in establishing proper gene silencing during early stages of development but is dispensable for their role in the proliferated germline. Svendsen et al. identify a requirement for the small RNA methyltransferase HENN-1 in germline immortality. HENN-1 is required for piRNA stability during embryogenesis but is dispensable in the adult germline, pointing to a role for piRNAs in establishing a gene regulatory network in embryos that protects the germline throughout development.
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Affiliation(s)
- Joshua M Svendsen
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Kailee J Reed
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Tarah Vijayasarathy
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Brooke E Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Rachel M Tucci
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Kristen C Brown
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA; Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Taylor N Marks
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Dieu An H Nguyen
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Carolyn M Phillips
- Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Taiowa A Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.
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38
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Dexheimer PJ, Cochella L. MicroRNAs: From Mechanism to Organism. Front Cell Dev Biol 2020; 8:409. [PMID: 32582699 PMCID: PMC7283388 DOI: 10.3389/fcell.2020.00409] [Citation(s) in RCA: 183] [Impact Index Per Article: 45.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/04/2020] [Indexed: 12/12/2022] Open
Abstract
MicroRNAs (miRNAs) are short, regulatory RNAs that act as post-transcriptional repressors of gene expression in diverse biological contexts. The emergence of small RNA-mediated gene silencing preceded the onset of multicellularity and was followed by a drastic expansion of the miRNA repertoire in conjunction with the evolution of complexity in the plant and animal kingdoms. Along this process, miRNAs became an essential feature of animal development, as no higher metazoan lineage tolerated loss of miRNAs or their associated protein machinery. In fact, ablation of the miRNA biogenesis machinery or the effector silencing factors results in severe embryogenesis defects in every animal studied. In this review, we summarize recent mechanistic insight into miRNA biogenesis and function, while emphasizing features that have enabled multicellular organisms to harness the potential of this broad class of repressors. We first discuss how different mechanisms of regulation of miRNA biogenesis are used, not only to generate spatio-temporal specificity of miRNA production within an animal, but also to achieve the necessary levels and dynamics of expression. We then explore how evolution of the mechanism for small RNA-mediated repression resulted in a diversity of silencing complexes that cause different molecular effects on their targets. Multicellular organisms have taken advantage of this variability in the outcome of miRNA-mediated repression, with differential use in particular cell types or even distinct subcellular compartments. Finally, we present an overview of how the animal miRNA repertoire has evolved and diversified, emphasizing the emergence of miRNA families and the biological implications of miRNA sequence diversification. Overall, focusing on selected animal models and through the lens of evolution, we highlight canonical mechanisms in miRNA biology and their variations, providing updated insight that will ultimately help us understand the contribution of miRNAs to the development and physiology of multicellular organisms.
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Affiliation(s)
- Philipp J Dexheimer
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Vienna, Austria
| | - Luisa Cochella
- Research Institute of Molecular Pathology (IMP), Vienna BioCenter (VBC), Vienna, Austria
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39
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Reed KJ, Svendsen JM, Brown KC, Montgomery BE, Marks TN, Vijayasarathy T, Parker DM, Nishimura EO, Updike DL, Montgomery TA. Widespread roles for piRNAs and WAGO-class siRNAs in shaping the germline transcriptome of Caenorhabditis elegans. Nucleic Acids Res 2020; 48:1811-1827. [PMID: 31872227 PMCID: PMC7038979 DOI: 10.1093/nar/gkz1178] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 12/05/2019] [Accepted: 12/06/2019] [Indexed: 12/31/2022] Open
Abstract
Piwi-interacting RNAs (piRNAs) and small interfering RNAs (siRNAs) are distinct classes of small RNAs required for proper germline development. To identify the roles of piRNAs and siRNAs in regulating gene expression in Caenorhabditis elegans, we subjected small RNAs and mRNAs from the gonads of piRNA and siRNA defective mutants to high-throughput sequencing. We show that piRNAs and an abundant class of siRNAs known as WAGO-class 22G-RNAs are required for proper expression of spermatogenic and oogenic genes. WAGO-class 22G-RNAs are also broadly required for transposon silencing, whereas piRNAs are largely dispensable. piRNAs, however, have a critical role in controlling histone gene expression. In the absence of piRNAs, histone mRNAs are misrouted into the nuclear RNAi pathway involving the Argonaute HRDE-1, concurrent with a reduction in the expression of many histone mRNAs. We also show that high-level gene expression in the germline is correlated with high level 22G-RNA production. However, most highly expressed genes produce 22G-RNAs through a distinct pathway that presumably involves the Argonaute CSR-1. In contrast, genes targeted by the WAGO branch of the 22G-RNA pathway are typically poorly expressed and respond unpredictably to loss of 22G-RNAs. Our results point to broad roles for piRNAs and siRNAs in controlling gene expression in the C. elegans germline.
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Affiliation(s)
- Kailee J Reed
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.,Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Joshua M Svendsen
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.,Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Kristen C Brown
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.,Cell and Molecular Biology Program, Colorado State University, Fort Collins, CO 80523, USA
| | - Brooke E Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Taylor N Marks
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Tarah Vijayasarathy
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Dylan M Parker
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Erin Osborne Nishimura
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Dustin L Updike
- Mount Desert Island Biological Laboratory, Bar Harbor, ME 04672, USA
| | - Taiowa A Montgomery
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
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40
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Doll MA, Soltanmohammadi N, Schumacher B. ALG-2/AGO-Dependent mir-35 Family Regulates DNA Damage-Induced Apoptosis Through MPK-1/ERK MAPK Signaling Downstream of the Core Apoptotic Machinery in Caenorhabditis elegans. Genetics 2019; 213:173-194. [PMID: 31296532 PMCID: PMC6727803 DOI: 10.1534/genetics.119.302458] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022] Open
Abstract
MicroRNAs (miRNAs) associate with argonaute (AGO) proteins to post-transcriptionally modulate the expression of genes involved in various cellular processes. Herein, we show that loss of the Caenorhabditis elegans AGO gene alg-2 results in rapid and significantly increased germ cell apoptosis in response to DNA damage inflicted by ionizing radiation (IR). We demonstrate that the abnormal apoptosis phenotype in alg-2 mutant animals can be explained by reduced expression of mir-35 miRNA family members. We show that the increased apoptosis levels in IR-treated alg-2 or mir-35 family mutants depend on a transient hyperactivation of the C. elegans ERK1/2 MAPK ortholog MPK-1 in dying germ cells. Unexpectedly, MPK-1 phosphorylation occurs downstream of caspase activation and depends at least in part on a functional cell corpse-engulfment machinery. Therefore, we propose a refined mechanism, in which an initial proapoptotic stimulus by the core apoptotic machinery initiates the engulfment process, which in turn activates MAPK signaling to facilitate the demise of genomically compromised germ cells.
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Affiliation(s)
- Markus Alexander Doll
- Institute for Genome Stability in Ageing and Disease, Medical Faculty, University of Cologne, 50931, Germany
- Cologne Excellence Cluster for Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931, Germany
| | - Najmeh Soltanmohammadi
- Institute for Genome Stability in Ageing and Disease, Medical Faculty, University of Cologne, 50931, Germany
- Cologne Excellence Cluster for Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931, Germany
| | - Björn Schumacher
- Institute for Genome Stability in Ageing and Disease, Medical Faculty, University of Cologne, 50931, Germany
- Cologne Excellence Cluster for Cellular Stress Responses in Ageing-Associated Diseases (CECAD), Center for Molecular Medicine Cologne (CMMC), University of Cologne, 50931, Germany
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41
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Kotagama K, Schorr AL, Steber HS, Mangone M. ALG-1 Influences Accurate mRNA Splicing Patterns in the Caenorhabditis elegans Intestine and Body Muscle Tissues by Modulating Splicing Factor Activities. Genetics 2019; 212:931-951. [PMID: 31073019 PMCID: PMC6614907 DOI: 10.1534/genetics.119.302223] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 05/06/2019] [Indexed: 01/05/2023] Open
Abstract
MicroRNAs (miRNAs) are known to modulate gene expression, but their activity at the tissue-specific level remains largely uncharacterized. To study their contribution to tissue-specific gene expression, we developed novel tools to profile putative miRNA targets in the Caenorhabditis elegans intestine and body muscle. We validated many previously described interactions and identified ∼3500 novel targets. Many of the candidate miRNA targets curated are known to modulate the functions of their respective tissues. Within our data sets we observed a disparity in the use of miRNA-based gene regulation between the intestine and body muscle. The intestine contained significantly more putative miRNA targets than the body muscle highlighting its transcriptional complexity. We detected an unexpected enrichment of RNA-binding proteins targeted by miRNA in both tissues, with a notable abundance of RNA splicing factors. We developed in vivo genetic tools to validate and further study three RNA splicing factors identified as putative miRNA targets in our study (asd-2, hrp-2, and smu-2), and show that these factors indeed contain functional miRNA regulatory elements in their 3'UTRs that are able to repress their expression in the intestine. In addition, the alternative splicing pattern of their respective downstream targets (unc-60, unc-52, lin-10, and ret-1) is dysregulated when the miRNA pathway is disrupted. A reannotation of the transcriptome data in C. elegans strains that are deficient in the miRNA pathway from past studies supports and expands on our results. This study highlights an unexpected role for miRNAs in modulating tissue-specific gene isoforms, where post-transcriptional regulation of RNA splicing factors associates with tissue-specific alternative splicing.
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Affiliation(s)
- Kasuen Kotagama
- Molecular and Cellular Biology Graduate Program, School of Life Sciences, Arizona State University, Tempe, Arizona 85287
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona
| | - Anna L Schorr
- Molecular and Cellular Biology Graduate Program, School of Life Sciences, Arizona State University, Tempe, Arizona 85287
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona
| | - Hannah S Steber
- Barrett, The Honors College, Arizona State University, Tempe, Arizona 85281
| | - Marco Mangone
- Molecular and Cellular Biology Graduate Program, School of Life Sciences, Arizona State University, Tempe, Arizona 85287
- Virginia G. Piper Center for Personalized Diagnostics, The Biodesign Institute at Arizona State University, Tempe, Arizona
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42
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Functional genomic analysis identifies miRNA repertoire regulating C. elegans oocyte development. Nat Commun 2018; 9:5318. [PMID: 30552320 PMCID: PMC6294007 DOI: 10.1038/s41467-018-07791-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 11/26/2018] [Indexed: 12/12/2022] Open
Abstract
Oocyte-specific miRNA function remains unclear in mice and worms because loss of Dgcr8 and Dicer from mouse and worm oocytes, respectively, does not yield oogenic defects. These data lead to several models: (a) miRNAs are not generated in oocytes; (b) miRNAs are generated but do not perform an oogenic function; (c) functional oocyte miRNAs are generated in a manner independent of these enzymes. Here, we test these models using a combination of genomic, expression and functional analyses on the C. elegans germline. We identify a repertoire of at least twenty-three miRNAs that accumulate in four spatial domains in oocytes. Genetic tests demonstrate that oocyte-expressed miRNAs regulate key oogenic processes within their respective expression domains. Unexpectedly, we find that over half of the oocyte-expressed miRNAs are generated through an unknown Drosha independent mechanism. Thus, a functional miRNA repertoire generated via Drosha dependent and independent pathways regulates C. elegans oocyte development.
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43
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Somatic and Germline MicroRNAs Form Distinct Silencing Complexes to Regulate Their Target mRNAs Differently. Dev Cell 2018; 47:239-247.e4. [PMID: 30245155 DOI: 10.1016/j.devcel.2018.08.022] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/31/2018] [Accepted: 08/23/2018] [Indexed: 11/23/2022]
Abstract
Animal germ cells possess a specific post-transcriptional regulatory context allowing the storage of maternal transcripts in the oocyte until their translation at a specific point in early development. As key regulators of gene expression, miRNAs repress translation mainly through mRNA destabilization. Thus, germline miRNAs likely use distinct ways to regulate their targets. Here, we use C. elegans to compare miRNA function within germline and somatic tissues. We show that the same miRNA displays tissue-specific gene regulatory mechanisms. While translational repression occurs in both tissues, targeted mRNAs are instead stabilized in the germline. Comparative analyses of miRNA silencing complexes (miRISC) demonstrate that their composition differs from germline to soma. We show that germline miRNA targets preferentially localize to perinuclear regions adjacent to P granules, and their repression is dependent on the core P granule component GLH-1. Together, our findings reveal the existence of different miRISC in animals that affect targeted mRNAs distinctively.
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44
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Berardi S, McFall A, Toledo-Hernandez A, Coote C, Graham H, Stine L, Rhodehouse K, Auernhamer A, Van Wynsberghe PM. The Period protein homolog LIN-42 regulates germline development in C. elegans. Mech Dev 2018; 153:42-53. [PMID: 30144508 DOI: 10.1016/j.mod.2018.08.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/20/2018] [Accepted: 08/20/2018] [Indexed: 10/28/2022]
Abstract
Germline stem cells are maintained in the distal region of the C. elegans gonad. These cells undergo mitotic divisions, and GLP-1/Notch signaling dictates whether they remain in this state. The somatic distal tip cell (DTC) caps the end of the distal gonad and is essential for maintenance of the germline mitotic zone. As germ cells move away from the DTC they exit mitosis and enter early meiotic prophase. Here we identify the Period protein homolog LIN-42 as a new regulator of germline development in C. elegans. LIN-42 is expressed in almost all somatic cells including the DTC, and LIN-42 functions as a transcription factor in the heterochronic pathway and to regulate molting. We found that the mitotic proliferative zone size in the distal gonad was significantly reduced by ~25% in lin-42 mutants compared to WT N2 worms. A lin-42 mutation also reduced the mitotic proliferative zone size caused by glp-1 partial loss-of-function and gain-of-function alleles. LIN-42 mediates this effect, at least in part, by regulating expression of the GLP-1/Notch ligand LAG-2. We further show that lin-42 expression itself is regulated by ATX-2, which promotes germline proliferation and is the homolog of the RNA binding protein ataxin-2 that is implicated in human neurodegenerative diseases. Altogether our results establish a new role for the conserved, important Period protein homolog LIN-42 in regulating early germline development. These results also suggest that in addition to regulating behavioral rhythms, the circadian clock plays an important role in communicating environmental signals to essential reproductive pathways.
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Affiliation(s)
- Skyler Berardi
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Alanna McFall
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | | | - Carolyn Coote
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Hillary Graham
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Laurel Stine
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Kyle Rhodehouse
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
| | - Anna Auernhamer
- Department of Biology, Colgate University, Hamilton, NY 13346, USA
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45
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Recent Molecular Genetic Explorations of Caenorhabditis elegans MicroRNAs. Genetics 2018; 209:651-673. [PMID: 29967059 PMCID: PMC6028246 DOI: 10.1534/genetics.118.300291] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 04/30/2018] [Indexed: 12/17/2022] Open
Abstract
MicroRNAs are small, noncoding RNAs that regulate gene expression at the post-transcriptional level in essentially all aspects of Caenorhabditis elegans biology. More than 140 genes that encode microRNAs in C. elegans regulate development, behavior, metabolism, and responses to physiological and environmental changes. Genetic analysis of C. elegans microRNA genes continues to enhance our fundamental understanding of how microRNAs are integrated into broader gene regulatory networks to control diverse biological processes, including growth, cell division, cell fate determination, behavior, longevity, and stress responses. As many of these microRNA sequences and the related processing machinery are conserved over nearly a billion years of animal phylogeny, the assignment of their functions via worm genetics may inform the functions of their orthologs in other animals, including humans. In vivo investigations are especially important for microRNAs because in silico extrapolation of their functions using mRNA target prediction programs can easily assign microRNAs to incorrect genetic pathways. At this mezzanine level of microRNA bioinformatic sophistication, genetic analysis continues to be the gold standard for pathway assignments.
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46
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Aalto AP, Nicastro IA, Broughton JP, Chipman LB, Schreiner WP, Chen JS, Pasquinelli AE. Opposing roles of microRNA Argonautes during Caenorhabditis elegans aging. PLoS Genet 2018; 14:e1007379. [PMID: 29927939 PMCID: PMC6013023 DOI: 10.1371/journal.pgen.1007379] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/25/2018] [Indexed: 01/08/2023] Open
Abstract
Argonaute (AGO) proteins partner with microRNAs (miRNAs) to target specific genes for post-transcriptional regulation. During larval development in Caenorhabditis elegans, Argonaute-Like Gene 1 (ALG-1) is the primary mediator of the miRNA pathway, while the related ALG-2 protein is largely dispensable. Here we show that in adult C. elegans these AGOs are differentially expressed and, surprisingly, work in opposition to each other; alg-1 promotes longevity, whereas alg-2 restricts lifespan. Transcriptional profiling of adult animals revealed that distinct miRNAs and largely non-overlapping sets of protein-coding genes are misregulated in alg-1 and alg-2 mutants. Interestingly, many of the differentially expressed genes are downstream targets of the Insulin/ IGF-1 Signaling (IIS) pathway, which controls lifespan by regulating the activity of the DAF-16/ FOXO transcription factor. Consistent with this observation, we show that daf-16 is required for the extended lifespan of alg-2 mutants. Furthermore, the long lifespan of daf-2 insulin receptor mutants, which depends on daf-16, is strongly reduced in animals lacking alg-1 activity. This work establishes an important role for AGO-mediated gene regulation in aging C. elegans and illustrates that the activity of homologous genes can switch from complementary to antagonistic, depending on the life stage. Tiny non-coding RNAs called microRNAs (miRNAs) are broadly conserved across animal species and have established roles in regulating development, metabolism and behavior. In humans, aberrant expression or function of specific miRNAs has been associated with a wide variety of diseases, underscoring the critical role of these molecules in organismal viability. Argonaute (AGO) proteins are essential co-factors for miRNAs to regulate the expression of target genes. In C. elegans nematodes, two highly related AGOs (ALG-1 and ALG-2; Argonaute-Like Genes) play largely overlapping roles in the miRNA pathway during development. Here we report that the activities of these two AGOs diverge in aging animals, as loss of ALG-1 shortens lifespan, while loss of ALG-2 extends it. These opposite longevity phenotypes are associated with differential regulation of specific miRNAs and protein-coding genes that act in the Insulin/ IGF-1 Signaling (IIS) pathway. Furthermore, we present genetic evidence that alg-1 and alg-2 operate within this pathway to impact aging. In sum, our findings reveal that two related AGOs function antagonistically within the conserved insulin signaling pathway that regulates longevity.
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Affiliation(s)
- Antti P. Aalto
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - Ian A. Nicastro
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - James P. Broughton
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - Laura B. Chipman
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - William P. Schreiner
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - Jerry S. Chen
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
| | - Amy E. Pasquinelli
- Division of Biology, University of California, San Diego, La Jolla, CA, United States of America
- * E-mail:
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47
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Affiliation(s)
- Kristen C. Brown
- Department of Biology, Colorado State University, Fort Collins, Colorado, United States of America
- Cell and Molecular Biology Program, Colorado State University, Fort Collins, Colorado, United States of America
| | - Taiowa A. Montgomery
- Department of Biology, Colorado State University, Fort Collins, Colorado, United States of America
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48
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Abstract
The window of embryonic development after fertilization but prior to the beginning of transcription from the zygotic genome is a period that relies heavily on post-transcriptional regulation of gene expression. MicroRNAs constitute one of the predominant mechanisms of post-transcriptional gene regulation, yet their biological function and molecular mechanism of action during this developmental window is poorly understood. Our recent findings demonstrate that the maternal contribution of mir-35 family members contributes to zygotic developmental decisions (sex determination) in C. elegans embryogenesis. Here, I discuss these finding in the context of data from C. elegans and other model organisms regarding the regulation of maternal microRNA activity in early animal embryogenesis.
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Affiliation(s)
- Katherine McJunkin
- a Laboratory of Cellular and Developmental Biology , National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , 50 South Drive, Bethesda , MD , USA
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