1
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Mangiavacchi A, Morelli G, Reppe S, Saera-Vila A, Liu P, Eggerschwiler B, Zhang H, Bensaddek D, Casanova EA, Medina Gomez C, Prijatelj V, Della Valle F, Atinbayeva N, Izpisua Belmonte JC, Rivadeneira F, Cinelli P, Gautvik KM, Orlando V. LINE-1 RNA triggers matrix formation in bone cells via a PKR-mediated inflammatory response. EMBO J 2024:10.1038/s44318-024-00143-z. [PMID: 38951609 DOI: 10.1038/s44318-024-00143-z] [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: 08/08/2023] [Revised: 05/16/2024] [Accepted: 05/23/2024] [Indexed: 07/03/2024] Open
Abstract
Transposable elements (TEs) are mobile genetic modules of viral derivation that have been co-opted to become modulators of mammalian gene expression. TEs are a major source of endogenous dsRNAs, signaling molecules able to coordinate inflammatory responses in various physiological processes. Here, we provide evidence for a positive involvement of TEs in inflammation-driven bone repair and mineralization. In newly fractured mice bone, we observed an early transient upregulation of repeats occurring concurrently with the initiation of the inflammatory stage. In human bone biopsies, analysis revealed a significant correlation between repeats expression, mechanical stress and bone mineral density. We investigated a potential link between LINE-1 (L1) expression and bone mineralization by delivering a synthetic L1 RNA to osteoporotic patient-derived mesenchymal stem cells and observed a dsRNA-triggered protein kinase (PKR)-mediated stress response that led to strongly increased mineralization. This response was associated with a strong and transient inflammation, accompanied by a global translation attenuation induced by eIF2α phosphorylation. We demonstrated that L1 transfection reshaped the secretory profile of osteoblasts, triggering a paracrine activity that stimulated the mineralization of recipient cells.
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Affiliation(s)
- Arianna Mangiavacchi
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia.
| | - Gabriele Morelli
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia
| | - Sjur Reppe
- Oslo University Hospital, Department of Medical Biochemistry, Oslo, Norway
- Lovisenberg Diaconal Hospital, Unger-Vetlesen Institute, Oslo, Norway
- Oslo University Hospital, Department of Plastic and Reconstructive Surgery, Oslo, Norway
| | | | - Peng Liu
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia
| | - Benjamin Eggerschwiler
- Department of Trauma, University Hospital Zurich, Sternwartstrasse 14, 8091, Zurich, Switzerland
- Life Science Zurich Graduate School, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Huoming Zhang
- Core Labs, King Abdullah University of Science and Technology (KAUST), Thuwal, 23500-6900, Kingdom of Saudi Arabia
| | - Dalila Bensaddek
- Core Labs, King Abdullah University of Science and Technology (KAUST), Thuwal, 23500-6900, Kingdom of Saudi Arabia
| | - Elisa A Casanova
- Sequentia Biotech, Carrer Comte D'Urgell 240, Barcelona, 08036, Spain
| | | | - Vid Prijatelj
- Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, the Netherlands
| | - Francesco Della Valle
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia
- Altos Labs, San Diego, CA, USA
| | - Nazerke Atinbayeva
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia
| | | | - Fernando Rivadeneira
- Department of Internal Medicine, Erasmus Medical Centre, Rotterdam, the Netherlands
| | - Paolo Cinelli
- Sequentia Biotech, Carrer Comte D'Urgell 240, Barcelona, 08036, Spain
- Center for Applied Biotechnology and Molecular Medicine, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | | | - Valerio Orlando
- King Abdullah University of Science and Technology (KAUST), Biological Environmental Science and Engineering Division, Thuwal, 23500-6900, Kingdom of Saudi Arabia.
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2
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Frost B. Alzheimer's disease and related tauopathies: disorders of disrupted neuronal identity. Trends Neurosci 2023; 46:797-813. [PMID: 37591720 PMCID: PMC10528597 DOI: 10.1016/j.tins.2023.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/20/2023] [Accepted: 07/24/2023] [Indexed: 08/19/2023]
Abstract
Postmitotic neurons require persistently active controls to maintain terminal differentiation. Unlike dividing cells, aberrant cell cycle activation in mature neurons causes apoptosis rather than transformation. In Alzheimer's disease (AD) and related tauopathies, evidence suggests that pathogenic forms of tau drive neurodegeneration via neuronal cell cycle re-entry. Multiple interconnected mechanisms linking tau to cell cycle activation have been identified, including, but not limited to, tau-induced overstabilization of the actin cytoskeleton, consequent changes to nuclear architecture, and disruption of heterochromatin-mediated gene silencing. Cancer- and development-associated pathways are upregulated in human and cellular models of tauopathy, and many tau-induced cellular phenotypes are also present in various cancers and progenitor/stem cells. In this review, I delve into mechanistic parallels between tauopathies, cancer, and development, and highlight the role of tau in cancer and in the developing brain. Based on these studies, I put forth a model by which pathogenic forms of tau disrupt the program that maintains terminal neuronal differentiation, driving cell cycle re-entry and consequent neuronal death. This framework presents tauopathies as conditions involving the profound toxic disruption of neuronal identity.
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Affiliation(s)
- Bess Frost
- Sam & Ann Barshop Institute for Longevity and Aging Studies, University of Texas Health San Antonio, San Antonio, TX, USA; Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, University of Texas Health San Antonio, San Antonio, TX, USA; Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA.
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3
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Correia JC, Jannig PR, Gosztyla ML, Cervenka I, Ducommun S, Præstholm SM, Dumont K, Liu Z, Liang Q, Edsgärd D, Emanuelsson O, Gregorevic P, Westerblad H, Venckunas T, Brazaitis M, Kamandulis S, Lanner JT, Yeo GW, Ruas JL. Zfp697 is an RNA-binding protein that regulates skeletal muscle inflammation and regeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544338. [PMID: 37398033 PMCID: PMC10312635 DOI: 10.1101/2023.06.12.544338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Muscular atrophy is a mortality risk factor that happens with disuse, chronic disease, and aging. Recovery from atrophy requires changes in several cell types including muscle fibers, and satellite and immune cells. Here we show that Zfp697/ZNF697 is a damage-induced regulator of muscle regeneration, during which its expression is transiently elevated. Conversely, sustained Zfp697 expression in mouse muscle leads to a gene expression signature of chemokine secretion, immune cell recruitment, and extracellular matrix remodeling. Myofiber-specific Zfp697 ablation hinders the inflammatory and regenerative response to muscle injury, compromising functional recovery. We uncover Zfp697 as an essential interferon gamma mediator in muscle cells, interacting primarily with ncRNAs such as the pro-regenerative miR-206. In sum, we identify Zfp697 as an integrator of cell-cell communication necessary for tissue regeneration.
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Affiliation(s)
- Jorge C. Correia
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Paulo R. Jannig
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Maya L. Gosztyla
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Igor Cervenka
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Serge Ducommun
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Stine M. Præstholm
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Kyle Dumont
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Zhengye Liu
- Molecular Muscle Physiology and Pathophysiology. Department of Physiology and Pharmacology, Biomedicum. Karolinska Institutet. SE-171 77, Stockholm. Sweden
| | - Qishan Liang
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Daniel Edsgärd
- Science for Life Laboratory, Department of Gene Technology, School of Engineering Sciences in Biotechnology, Chemistry and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Olof Emanuelsson
- Science for Life Laboratory, Department of Gene Technology, School of Engineering Sciences in Biotechnology, Chemistry and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Paul Gregorevic
- Centre for Muscle Research, Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Melbourne, VIC, Australia
| | - Håkan Westerblad
- Muscle Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
| | - Tomas Venckunas
- Institute of Sports Science and Innovations, Lithuanian Sports University, 44221 Kaunas, Lithuania
| | - Marius Brazaitis
- Institute of Sports Science and Innovations, Lithuanian Sports University, 44221 Kaunas, Lithuania
| | - Sigitas Kamandulis
- Institute of Sports Science and Innovations, Lithuanian Sports University, 44221 Kaunas, Lithuania
| | - Johanna T. Lanner
- Molecular Muscle Physiology and Pathophysiology. Department of Physiology and Pharmacology, Biomedicum. Karolinska Institutet. SE-171 77, Stockholm. Sweden
| | - Gene W. Yeo
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Jorge L. Ruas
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum. Karolinska. SE-171 77, Stockholm, Sweden
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4
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Angileri KM, Bagia NA, Feschotte C. Transposon control as a checkpoint for tissue regeneration. Development 2022; 149:dev191957. [PMID: 36440631 PMCID: PMC10655923 DOI: 10.1242/dev.191957] [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: 03/11/2022] [Accepted: 10/03/2022] [Indexed: 11/29/2022]
Abstract
Tissue regeneration requires precise temporal control of cellular processes such as inflammatory signaling, chromatin remodeling and proliferation. The combination of these processes forms a unique microenvironment permissive to the expression, and potential mobilization of, transposable elements (TEs). Here, we develop the hypothesis that TE activation creates a barrier to tissue repair that must be overcome to achieve successful regeneration. We discuss how uncontrolled TE activity may impede tissue restoration and review mechanisms by which TE activity may be controlled during regeneration. We posit that the diversification and co-evolution of TEs and host control mechanisms may contribute to the wide variation in regenerative competency across tissues and species.
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Affiliation(s)
- Krista M. Angileri
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
| | - Nornubari A. Bagia
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
| | - Cedric Feschotte
- Department of Molecular Biology and Genetics, Cornell University, 526 Campus Rd, Ithaca, NY 14850, USA
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5
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Medina-Feliciano JG, García-Arrarás JE. Regeneration in Echinoderms: Molecular Advancements. Front Cell Dev Biol 2021; 9:768641. [PMID: 34977019 PMCID: PMC8718600 DOI: 10.3389/fcell.2021.768641] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/01/2021] [Indexed: 12/18/2022] Open
Abstract
Which genes and gene signaling pathways mediate regenerative processes? In recent years, multiple studies, using a variety of animal models, have aimed to answer this question. Some answers have been obtained from transcriptomic and genomic studies where possible gene and gene pathway candidates thought to be involved in tissue and organ regeneration have been identified. Several of these studies have been done in echinoderms, an animal group that forms part of the deuterostomes along with vertebrates. Echinoderms, with their outstanding regenerative abilities, can provide important insights into the molecular basis of regeneration. Here we review the available data to determine the genes and signaling pathways that have been proposed to be involved in regenerative processes. Our analyses provide a curated list of genes and gene signaling pathways and match them with the different cellular processes of the regenerative response. In this way, the molecular basis of echinoderm regenerative potential is revealed, and is available for comparisons with other animal taxa.
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6
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Larocca D, Lee J, West MD, Labat I, Sternberg H. No Time to Age: Uncoupling Aging from Chronological Time. Genes (Basel) 2021; 12:611. [PMID: 33919082 PMCID: PMC8143125 DOI: 10.3390/genes12050611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 04/13/2021] [Accepted: 04/16/2021] [Indexed: 12/20/2022] Open
Abstract
Multicellular life evolved from simple unicellular organisms that could replicate indefinitely, being essentially ageless. At this point, life split into two fundamentally different cell types: the immortal germline representing an unbroken lineage of cell division with no intrinsic endpoint and the mortal soma, which ages and dies. In this review, we describe the germline as clock-free and the soma as clock-bound and discuss aging with respect to three DNA-based cellular clocks (telomeric, DNA methylation, and transposable element). The ticking of these clocks corresponds to the stepwise progressive limitation of growth and regeneration of somatic cells that we term somatic restriction. Somatic restriction acts in opposition to strategies that ensure continued germline replication and regeneration. We thus consider the plasticity of aging as a process not fixed to the pace of chronological time but one that can speed up or slow down depending on the rate of intrinsic cellular clocks. We further describe how germline factor reprogramming might be used to slow the rate of aging and potentially reverse it by causing the clocks to tick backward. Therefore, reprogramming may eventually lead to therapeutic strategies to treat degenerative diseases by altering aging itself, the one condition common to us all.
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Affiliation(s)
| | - Jieun Lee
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Michael D. West
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Ivan Labat
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
| | - Hal Sternberg
- AgeX Therapeutics Inc., Alameda, CA 94501, USA; (J.L.); (M.D.W.); (I.L.); (H.S.)
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7
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Sessions SK, Wake DB. Forever young: Linking regeneration and genome size in salamanders. Dev Dyn 2020; 250:768-778. [DOI: 10.1002/dvdy.279] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/21/2020] [Accepted: 11/11/2020] [Indexed: 11/12/2022] Open
Affiliation(s)
| | - David B. Wake
- Department of Integrative Biology and Museum of Vertebrate Zoology University of California Berkeley California USA
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8
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García‐Lepe UO, Cruz‐Ramírez A, Bermúdez‐Cruz RM. DNA repair during regeneration in
Ambystoma mexicanum. Dev Dyn 2020; 250:788-799. [DOI: 10.1002/dvdy.276] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/19/2020] [Accepted: 12/03/2020] [Indexed: 12/22/2022] Open
Affiliation(s)
- Ulises Omar García‐Lepe
- Genetics and Molecular Biology Department Centro de Investigacion y Estudios Avanzados del IPN Mexico city Mexico
| | - Alfredo Cruz‐Ramírez
- Molecular and Developmental Complexity Group Unidad de Genómica Avanzada (LANGEBIO), Centro de Investigación y de Estudios Avanzados del IPN Guanajuato Mexico
| | - Rosa María Bermúdez‐Cruz
- Genetics and Molecular Biology Department Centro de Investigacion y Estudios Avanzados del IPN Mexico city Mexico
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9
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Verissimo KM, Perez LN, Dragalzew AC, Senevirathne G, Darnet S, Barroso Mendes WR, Ariel Dos Santos Neves C, Monteiro Dos Santos E, Nazare de Sousa Moraes C, Elewa A, Shubin N, Fröbisch NB, de Freitas Sousa J, Schneider I. Salamander-like tail regeneration in the West African lungfish. Proc Biol Sci 2020; 287:20192939. [PMID: 32933441 DOI: 10.1098/rspb.2019.2939] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Salamanders, frog tadpoles and diverse lizards have the remarkable ability to regenerate tails. Palaeontological data suggest that this capacity is plesiomorphic, yet when the developmental and genetic architecture of tail regeneration arose is poorly understood. Here, we show morphological and molecular hallmarks of tetrapod tail regeneration in the West African lungfish Protopterus annectens, a living representative of the sister group of tetrapods. As in salamanders, lungfish tail regeneration occurs via the formation of a proliferative blastema and restores original structures, including muscle, skeleton and spinal cord. In contrast with lizards and similar to salamanders and frogs, lungfish regenerate spinal cord neurons and reconstitute dorsoventral patterning of the tail. Similar to salamander and frog tadpoles, Shh is required for lungfish tail regeneration. Through RNA-seq analysis of uninjured and regenerating tail blastema, we show that the genetic programme deployed during lungfish tail regeneration maintains extensive overlap with that of tetrapods, with the upregulation of genes and signalling pathways previously implicated in amphibian and lizard tail regeneration. Furthermore, the lungfish tail blastema showed marked upregulation of genes encoding post-transcriptional RNA processing components and transposon-derived genes. Our results show that the developmental processes and genetic programme of tetrapod tail regeneration were present at least near the base of the sarcopterygian clade and establish the lungfish as a valuable research system for regenerative biology.
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Affiliation(s)
- Kellen Matos Verissimo
- Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-900, Belém, Brazil
| | - Louise Neiva Perez
- Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-900, Belém, Brazil.,Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, 10115 Berlin, Germany
| | - Aline Cutrim Dragalzew
- Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-900, Belém, Brazil
| | - Gayani Senevirathne
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
| | - Sylvain Darnet
- Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-900, Belém, Brazil
| | | | | | | | | | - Ahmed Elewa
- Department of Cell and Molecular Biology, Karolinska Institute, S-171 77, Stockholm, Sweden
| | - Neil Shubin
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
| | - Nadia Belinda Fröbisch
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, 10115 Berlin, Germany
| | | | - Igor Schneider
- Instituto de Ciências Biológicas, Universidade Federal do Pará, 66075-900, Belém, Brazil.,Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
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10
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Site-Specific Expression Pattern of PIWI-Interacting RNA in Skin and Oral Mucosal Wound Healing. Int J Mol Sci 2020; 21:ijms21020521. [PMID: 31947648 PMCID: PMC7013508 DOI: 10.3390/ijms21020521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 01/02/2020] [Accepted: 01/11/2020] [Indexed: 12/24/2022] Open
Abstract
The oral mucosa exhibits exceptional healing capability when compared to skin. Recent studies suggest that intrinsic differences in coding genes and regulatory small non-coding RNA (sncRNA) genes (e.g., microRNAs) may underlie the exceptional healing that occurs in the oral mucosa. Here, we investigate the role of a novel class of sncRNA-Piwi-interacting RNA (piRNA)-in the tissue-specific differential response to injury. An abundance of piRNAs was detected in both skin and oral mucosal epithelium during wound healing. The expression of PIWI genes (the obligate binding partners of piRNAs) was also detected in skin and oral wound healing. This data suggested that PIWI-piRNA machinery may serve an unknown function in the highly orchestrated wound healing process. Furthermore, unique tissue-specific piRNA profiles were obtained in the skin and oral mucosal epithelium, and substantially more changes in piRNA expression were observed during skin wound healing than oral mucosal wound healing. Thus, we present the first clue suggesting a role of piRNA in wound healing, and provide the first site-specific piRNA profile of skin and oral mucosal wound healing. These results serve as a foundation for the future investigation of the functional contribution(s) of piRNA in wound repair and tissue regeneration.
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11
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Wong AY, Whited JL. Parallels between wound healing, epimorphic regeneration and solid tumors. Development 2020; 147:147/1/dev181636. [PMID: 31898582 DOI: 10.1242/dev.181636] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Striking similarities between wound healing, epimorphic regeneration and the progression of solid tumors have been uncovered by recent studies. In this Review, we discuss systemic effects of tumorigenesis that are now being appreciated in epimorphic regeneration, including genetic, cellular and metabolic heterogeneity, changes in circulating factors, and the complex roles of immune cells and immune modulation at systemic and local levels. We suggest that certain mechanisms enabling regeneration may be co-opted by cancer to promote growth at primary and metastatic sites. Finally, we advocate that working with a unified approach could complement research in both fields.
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Affiliation(s)
- Alan Y Wong
- Harvard/MIT MD-PhD Program, Harvard Medical School, Boston, MA 02138, USA
| | - Jessica L Whited
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
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12
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Vieira WA, Wells KM, McCusker CD. Advancements to the Axolotl Model for Regeneration and Aging. Gerontology 2019; 66:212-222. [PMID: 31779024 DOI: 10.1159/000504294] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 10/22/2019] [Indexed: 12/12/2022] Open
Abstract
Loss of regenerative capacity is a normal part of aging. However, some organisms, such as the Mexican axolotl, retain striking regenerative capacity throughout their lives. Moreover, the development of age-related diseases is rare in this organism. In this review, we will explore how axolotls are used as a model system to study regenerative processes, the exciting new technological advancements now available for this model, and how we can apply the lessons we learn from studying regeneration in the axolotl to understand, and potentially treat, age-related decline in humans.
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Affiliation(s)
- Warren A Vieira
- Department of Biology, University of Massachusetts, Boston, Massachusetts, USA
| | - Kaylee M Wells
- Department of Biology, University of Massachusetts, Boston, Massachusetts, USA
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13
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Matsunami M, Suzuki M, Haramoto Y, Fukui A, Inoue T, Yamaguchi K, Uchiyama I, Mori K, Tashiro K, Ito Y, Takeuchi T, Suzuki KIT, Agata K, Shigenobu S, Hayashi T. A comprehensive reference transcriptome resource for the Iberian ribbed newt Pleurodeles waltl, an emerging model for developmental and regeneration biology. DNA Res 2019; 26:217-229. [PMID: 31006799 PMCID: PMC6589553 DOI: 10.1093/dnares/dsz003] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 02/28/2019] [Indexed: 12/14/2022] Open
Abstract
Urodele newts have unique biological properties, notably including prominent regeneration ability. The Iberian ribbed newt, Pleurodeles waltl, is a promising model amphibian distinguished by ease of breeding and efficient transgenic and genome editing methods. However, limited genetic information is available for P. waltl. We conducted an intensive transcriptome analysis of P. waltl using RNA-sequencing to build and annotate gene models. We generated 1.2 billion Illumina reads from a wide variety of samples across 12 different tissues/organs, unfertilized egg, and embryos at eight different developmental stages. These reads were assembled into 1,395,387 contigs, from which 202,788 non-redundant ORF models were constructed. The set is expected to cover a large fraction of P. waltl protein-coding genes, as confirmed by BUSCO analysis, where 98% of universal single-copy orthologs were identified. Ortholog analyses revealed the gene repertoire evolution of urodele amphibians. Using the gene set as a reference, gene network analysis identified regeneration-, developmental-stage-, and tissue-specific co-expressed gene modules. Our transcriptome resource is expected to enhance future research employing this emerging model animal for regeneration research as well as for investigations in other areas including developmental biology, stem cell biology, and cancer research. These data are available via our portal website, iNewt (http://www.nibb.ac.jp/imori/main/).
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Affiliation(s)
- Masatoshi Matsunami
- Department of Advanced Genomics and Laboratory Medicine, Graduate School of Medicine, University of the Ryukyus, Nishihara-Cho, Okinawa, Japan
| | - Miyuki Suzuki
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashihiroshima, Hiroshima, Japan
| | - Yoshikazu Haramoto
- Biotechnology Research Institute for Drug Discovery, Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | - Akimasa Fukui
- Department of Biological Sciences, Faculty of Science and Engineering, Chuo University, Bunkyo-Ku, Tokyo, Japan
| | - Takeshi Inoue
- Department of Life Science, Faculty of Science, Gakushuin University, Toshima-Ku, Tokyo, Japan
| | - Katsushi Yamaguchi
- Functional Genomics Facility, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Ikuo Uchiyama
- NIBB Core Research Facilities, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Kazuki Mori
- Computational Bio Big-Data Open Innovation Lab. (CBBD-OIL), Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Shinjuku-Ku, Tokyo, Japan
| | - Kosuke Tashiro
- Laboratory of Molecular Gene Technology, Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Yuzuru Ito
- Biotechnology Research Institute for Drug Discovery, Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
| | - Takashi Takeuchi
- Department of Biomedical Sciences, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
| | - Ken-ichi T Suzuki
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashihiroshima, Hiroshima, Japan
- Center for the Development of New Model Organisms, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Kiyokazu Agata
- Department of Life Science, Faculty of Science, Gakushuin University, Toshima-Ku, Tokyo, Japan
| | - Shuji Shigenobu
- NIBB Core Research Facilities, National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Toshinori Hayashi
- Department of Biomedical Sciences, School of Life Science, Faculty of Medicine, Tottori University, Yonago, Tottori, Japan
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14
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Díaz-Castillo C. Transcriptome dynamics along axolotl regenerative development are consistent with an extensive reduction in gene expression heterogeneity in dedifferentiated cells. PeerJ 2017; 5:e4004. [PMID: 29134148 PMCID: PMC5678507 DOI: 10.7717/peerj.4004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 10/18/2017] [Indexed: 12/13/2022] Open
Abstract
Although in recent years the study of gene expression variation in the absence of genetic or environmental cues or gene expression heterogeneity has intensified considerably, many basic and applied biological fields still remain unaware of how useful the study of gene expression heterogeneity patterns might be for the characterization of biological systems and/or processes. Largely based on the modulator effect chromatin compaction has for gene expression heterogeneity and the extensive changes in chromatin compaction known to occur for specialized cells that are naturally or artificially induced to revert to less specialized states or dedifferentiate, I recently hypothesized that processes that concur with cell dedifferentiation would show an extensive reduction in gene expression heterogeneity. The confirmation of the existence of such trend could be of wide interest because of the biomedical and biotechnological relevance of cell dedifferentiation-based processes, i.e., regenerative development, cancer, human induced pluripotent stem cells, or plant somatic embryogenesis. Here, I report the first empirical evidence consistent with the existence of an extensive reduction in gene expression heterogeneity for processes that concur with cell dedifferentiation by analyzing transcriptome dynamics along forearm regenerative development in Ambystoma mexicanum or axolotl. Also, I briefly discuss on the utility of the study of gene expression heterogeneity dynamics might have for the characterization of cell dedifferentiation-based processes, and the engineering of tools that afforded better monitoring and modulating such processes. Finally, I reflect on how a transitional reduction in gene expression heterogeneity for dedifferentiated cells can promote a long-term increase in phenotypic heterogeneity following cell dedifferentiation with potential adverse effects for biomedical and biotechnological applications.
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Small RNAs from a Big Genome: The piRNA Pathway and Transposable Elements in the Salamander Species Desmognathus fuscus. J Mol Evol 2016; 83:126-136. [PMID: 27743003 DOI: 10.1007/s00239-016-9759-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 10/06/2016] [Indexed: 01/26/2023]
Abstract
Most of the largest vertebrate genomes are found in salamanders, a clade of amphibians that includes 686 species. Salamander genomes range in size from 14 to 120 Gb, reflecting the accumulation of large numbers of transposable element (TE) sequences from all three TE classes. Although DNA loss rates are slow in salamanders relative to other vertebrates, high levels of TE insertion are also likely required to explain such high TE loads. Across the Tree of Life, novel TE insertions are suppressed by several pathways involving small RNA molecules. In most known animals, TE activity in the germline is primarily regulated by the Piwi-interacting RNA (piRNA) pathway. In this study, we test the hypothesis that salamanders' unusually high TE loads reflect the loss of the ancestral piRNA-mediated TE-silencing machinery. We characterized the small RNA pool in the female and male adult gonads, testing for the presence of small RNA molecules that bear the characteristics of TE-targeting piRNAs. We also analyzed the amino acid sequences of piRNA pathway proteins from salamanders and other vertebrates, testing whether the overall patterns of sequence divergence are consistent with conserved pathway function across the vertebrate clade. Our results do not support the hypothesis of piRNA pathway loss; instead, they suggest that the piRNA pathway is expressed in salamanders. Given these results, we propose hypotheses to explain how the extraordinary TE loads in salamander genomes could have accumulated, despite the expression of TE-silencing machinery.
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Khan A, Yadav NS, Morgenstern Y, Zemach A, Grafi G. Activation of Tag1 transposable elements in Arabidopsis dedifferentiating cells and their regulation by CHROMOMETHYLASE 3-mediated CHG methylation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2016; 1859:1289-98. [PMID: 27475038 DOI: 10.1016/j.bbagrm.2016.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Revised: 07/13/2016] [Accepted: 07/25/2016] [Indexed: 12/11/2022]
Abstract
Dedifferentiation, that is, the acquisition of stem cell-like state, commonly induced by stress (e.g., protoplasting), is characterized by open chromatin conformation, a chromatin state that could lead to activation of transposable elements (TEs). Here, we studied the activation of the Arabidopsis class II TE Tag1, in which two copies, situated close to each other (near genes) on chromosome 1 are found in Landsberg erecta (Ler) but not in Columbia (Col). We first transformed protoplasts with a construct in which a truncated Tag1 (ΔTag1 non-autonomous) blocks the expression of a reporter gene AtMBD5-GFP and found a relatively high ectopic excision of ΔTag1 accompanied by expression of AtMBD5-GFP in protoplasts derived from Ler compared to Col; further increase was observed in ddm1 (decrease in DNA methylation1) protoplasts (Ler background). Ectopic excision was associated with transcription of the endogenous Tag1 and changes in histone H3 methylation at the promoter region. Focusing on the endogenous Tag1 elements we found low level of excision in Ler protoplasts, which was slightly and strongly enhanced in ddm1 and cmt3 (chromomethylase3) protoplasts, respectively, concomitantly with reduction in Tag1 gene body (GB) CHG methylation and increased Tag1 transcription; strong activation of Tag1 was also observed in cmt3 leaves. Notably, in cmt3, but not in ddm1, Tag1 elements were excised out from their original sites and transposed elsewhere in the genome. Our results suggest that dedifferentiation is associated with Tag1 activation and that CMT3 rather than DDM1 plays a central role in restraining Tag1 activation via inducing GB CHG methylation.
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Affiliation(s)
- Asif Khan
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Narendra Singh Yadav
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Yaakov Morgenstern
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel
| | - Assaf Zemach
- Department of Molecular Biology and Ecology of Plants, Tel-Aviv University, 69978 Tel Aviv, Israel
| | - Gideon Grafi
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben Gurion 84990, Israel.
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17
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Rangasamy D, Lenka N, Ohms S, Dahlstrom JE, Blackburn AC, Board PG. Activation of LINE-1 Retrotransposon Increases the Risk of Epithelial-Mesenchymal Transition and Metastasis in Epithelial Cancer. Curr Mol Med 2016; 15:588-97. [PMID: 26321759 PMCID: PMC5384359 DOI: 10.2174/1566524015666150831130827] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 07/31/2015] [Accepted: 08/27/2015] [Indexed: 12/12/2022]
Abstract
Epithelial cancers comprise 80-90% of human cancers. During the process of cancer progression, cells lose their epithelial characteristics and acquire stem-like mesenchymal features that are resistant to chemotherapy. This process, termed the epithelial-mesenchymal transition (EMT), plays a critical role in the development of metastases. Because of the unique migratory and invasive properties of cells undergoing the EMT, therapeutic control of the EMT offers great hope and new opportunities for treating cancer. In recent years, a plethora of genes and noncoding RNAs, including miRNAs, have been linked to the EMT and the acquisition of stem cell-like properties. Despite these advances, questions remain unanswered about the molecular processes underlying such a cellular transition. In this article, we discuss how expression of the normally repressed LINE-1 (or L1) retrotransposons activates the process of EMT and the development of metastases. L1 is rarely expressed in differentiated stem cells or adult somatic tissues. However, its expression is widespread in almost all epithelial cancers and in stem cells in their undifferentiated state, suggesting a link between L1 activity and the proliferative and metastatic behaviour of cancer cells. We present an overview of L1 activity in cancer cells including how genes involved in proliferation, invasive and metastasis are modulated by L1 expression. The role of L1 in the differential expression of the let-7 family of miRNAs (that regulate genes involved in the EMT and metastasis) is also discussed. We also summarize recent novel insights into the role of the L1-encoded reverse transcriptase enzyme in epithelial cell plasticity that suggest it might be a potential therapeutic target that could reverse the EMT and the metastasis-associated stem cell-like properties of cancer cells.
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Affiliation(s)
- D Rangasamy
- John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory 2601, Australia.
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18
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Luo YB, Zhang L, Lin ZL, Ma JY, Jia J, Namgoong S, Sun QY. Distinct subcellular localization and potential role of LINE1-ORF1P in meiotic oocytes. Histochem Cell Biol 2015; 145:93-104. [PMID: 26464247 DOI: 10.1007/s00418-015-1369-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/30/2015] [Indexed: 02/06/2023]
Abstract
LINE-1 is an autonomous non-LTR retrotransposon in mammalian genomes and encodes ORF1P and ORF2P. ORF2P has been clearly identified as the enzyme supplier needed in LINE-1 retrotransposition. However, the role of ORF1P is not well explored. In this study, we employed loss/gain-of-function approach to investigate the role of LINE1-ORF1P in mouse oocyte meiotic maturation. During mouse oocyte development, ORF1P was observed in cytoplasm as well as in nucleus at germinal vesicle (GV) stage while was localized on the spindle after germinal vesicle breakdown (GVBD). Depletion of ORF1P caused oocyte arrest at the GV stage as well as down-regulation of CDC2 and CYCLIN B1, components of the maturation-promoting factor (MPF). Further analysis demonstrated ORF1P depletion triggered DNA damage response and most of the oocytes presented altered chromatin configuration. In addition, SMAD4 showed nuclear foci signal after Orf1p dsRNA injection. ORF1P overexpression held the oocyte development at MI stage and the chromosome alignment and spindle organization were severely affected. We also found that ORF1P could form DCP1A body-like foci structure in both cytoplasm and nucleus after heat shock. Taken together, accurate regulation of ORF1P plays an essential role in mouse oocyte meiotic maturation.
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Affiliation(s)
- Yi-Bo Luo
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Beijing, China.,Department of Animal Science, Chungbuk National University, Cheongju, Korea
| | - Li Zhang
- Hebei Key Laboratory of Animal Science, Hebei Medical University, Shijiazhuang, China
| | - Zi-Li Lin
- Department of Animal Science, Chungbuk National University, Cheongju, Korea
| | - Jun-Yu Ma
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Beijing, China
| | - Jialin Jia
- Department of Animal Science, Chungbuk National University, Cheongju, Korea
| | - Suk Namgoong
- Department of Animal Science, Chungbuk National University, Cheongju, Korea
| | - Qing-Yuan Sun
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Beijing, China.
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Petersen HO, Höger SK, Looso M, Lengfeld T, Kuhn A, Warnken U, Nishimiya-Fujisawa C, Schnölzer M, Krüger M, Özbek S, Simakov O, Holstein TW. A Comprehensive Transcriptomic and Proteomic Analysis of Hydra Head Regeneration. Mol Biol Evol 2015; 32:1928-47. [PMID: 25841488 PMCID: PMC4833066 DOI: 10.1093/molbev/msv079] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The cnidarian freshwater polyp Hydra sp. exhibits an unparalleled regeneration capacity in the animal kingdom. Using an integrative transcriptomic and stable isotope labeling by amino acids in cell culture proteomic/phosphoproteomic approach, we studied stem cell-based regeneration in Hydra polyps. As major contributors to head regeneration, we identified diverse signaling pathways adopted for the regeneration response as well as enriched novel genes. Our global analysis reveals two distinct molecular cascades: an early injury response and a subsequent, signaling driven patterning of the regenerating tissue. A key factor of the initial injury response is a general stabilization of proteins and a net upregulation of transcripts, which is followed by a subsequent activation cascade of signaling molecules including Wnts and transforming growth factor (TGF) beta-related factors. We observed moderate overlap between the factors contributing to proteomic and transcriptomic responses suggesting a decoupled regulation between the transcriptional and translational levels. Our data also indicate that interstitial stem cells and their derivatives (e.g., neurons) have no major role in Hydra head regeneration. Remarkably, we found an enrichment of evolutionarily more recent genes in the early regeneration response, whereas conserved genes are more enriched in the late phase. In addition, genes specific to the early injury response were enriched in transposon insertions. Genetic dynamicity and taxon-specific factors might therefore play a hitherto underestimated role in Hydra regeneration.
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Affiliation(s)
- Hendrik O Petersen
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Stefanie K Höger
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Mario Looso
- Max Planck Institute (MPI) for Heart and Lung Research, Bad Nauheim, Germany
| | - Tobias Lengfeld
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Anne Kuhn
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Uwe Warnken
- Functional Proteome Analysis Unit, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Chiemi Nishimiya-Fujisawa
- Okazaki Institute for Integrative Bioscience, National Institute for Basic Biology, Myodaiji, Okazaki, Japan
| | - Martina Schnölzer
- Functional Proteome Analysis Unit, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Marcus Krüger
- Max Planck Institute (MPI) for Heart and Lung Research, Bad Nauheim, Germany CECAD, University of Cologne, Germany
| | - Suat Özbek
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
| | - Oleg Simakov
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany Molecular Genetics Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Thomas W Holstein
- Centre for Organismal Studies (COS), Heidelberg University, Heidelberg, Germany
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20
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Rapp YG, Ransbotyn V, Grafi G. Senescence Meets Dedifferentiation. PLANTS 2015; 4:356-68. [PMID: 27135333 PMCID: PMC4844402 DOI: 10.3390/plants4030356] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/16/2015] [Accepted: 06/23/2015] [Indexed: 01/07/2023]
Abstract
Senescence represents the final stage of leaf development but is often induced prematurely following exposure to biotic and abiotic stresses. Leaf senescence is manifested by color change from green to yellow (due to chlorophyll degradation) or to red (due to de novo synthesis of anthocyanins coupled with chlorophyll degradation) and frequently culminates in programmed death of leaves. However, the breakdown of chlorophyll and macromolecules such as proteins and RNAs that occurs during leaf senescence does not necessarily represent a one-way road to death but rather a reversible process whereby senescing leaves can, under certain conditions, re-green and regain their photosynthetic capacity. This phenomenon essentially distinguishes senescence from programmed cell death, leading researchers to hypothesize that changes occurring during senescence might represent a process of trans-differentiation, that is the conversion of one cell type to another. In this review, we highlight attributes common to senescence and dedifferentiation including chromatin structure and activation of transposable elements and provide further support to the notion that senescence is not merely a deterioration process leading to death but rather a unique developmental state resembling dedifferentiation.
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Affiliation(s)
- Yemima Givaty Rapp
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, 84990 Israel.
| | - Vanessa Ransbotyn
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, 84990 Israel.
| | - Gideon Grafi
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, 84990 Israel.
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21
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Sun C, Mueller RL. Hellbender genome sequences shed light on genomic expansion at the base of crown salamanders. Genome Biol Evol 2015; 6:1818-29. [PMID: 25115007 PMCID: PMC4122941 DOI: 10.1093/gbe/evu143] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Among animals, genome sizes range from 20 Mb to 130 Gb, with 380-fold variation across vertebrates. Most of the largest vertebrate genomes are found in salamanders, an amphibian clade of 660 species. Thus, salamanders are an important system for studying causes and consequences of genomic gigantism. Previously, we showed that plethodontid salamander genomes accumulate higher levels of long terminal repeat (LTR) retrotransposons than do other vertebrates, although the evolutionary origins of such sequences remained unexplored. We also showed that some salamanders in the family Plethodontidae have relatively slow rates of DNA loss through small insertions and deletions. Here, we present new data from Cryptobranchus alleganiensis, the hellbender. Cryptobranchus and Plethodontidae span the basal phylogenetic split within salamanders; thus, analyses incorporating these taxa can shed light on the genome of the ancestral crown salamander lineage, which underwent expansion. We show that high levels of LTR retrotransposons likely characterize all crown salamanders, suggesting that disproportionate expansion of this transposable element (TE) class contributed to genomic expansion. Phylogenetic and age distribution analyses of salamander LTR retrotransposons indicate that salamanders' high TE levels reflect persistence and diversification of ancestral TEs rather than horizontal transfer events. Finally, we show that relatively slow DNA loss rates through small indels likely characterize all crown salamanders, suggesting that a decreased DNA loss rate contributed to genomic expansion at the clade's base. Our identification of shared genomic features across phylogenetically distant salamanders is a first step toward identifying the evolutionary processes underlying accumulation and persistence of high levels of repetitive sequence in salamander genomes.
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Abstract
Regeneration is studied in a few model species of salamanders, but the ten families of salamanders show considerable variation, and this has implications for our understanding of salamander biology. The most recent classification of the families identifies the cryptobranchoidea as the basal group which diverged in the early Jurassic. Variation in the sizes of genomes is particularly obvious, and reflects a major contribution from transposable elements which is already present in the basal group.Limb development has been a focus for evodevo studies, in part because of the variable property of pre-axial dominance which distinguishes salamanders from other tetrapods. This is thought to reflect the selective pressures that operate on a free-living aquatic larva, and might also be relevant for the evolution of limb regeneration. Recent fossil evidence suggests that both pre-axial dominance and limb regeneration were present 300 million years ago in larval temnospondyl amphibians that lived in mountain lakes. A satisfying account of regeneration in salamanders may need to address all these different aspects in the future.
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Mashanov VS, Zueva OR, García-Arrarás JE. Retrotransposons in animal regeneration: Overlooked components of the regenerative machinery? Mob Genet Elements 2014; 2:244-247. [PMID: 23550104 PMCID: PMC3575433 DOI: 10.4161/mge.22644] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Research on the involvement of retroelements in developmental processes has been gaining momentum recently; however, most of the studies published so far have been focused on embryonic development. This commentary presents two recent papers, which document significant changes in transcriptional activity of retroelements in two different model systems, salamander limb regeneration and regeneration of radial organs in the sea cucumber Holothuria glaberrima. We hypothesize that transcriptional activity of the retrotransposons can be specifically controlled by the host and may play some hitherto unrecognized role in regeneration.
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The link between injury-induced stress and regenerative phenomena: A cellular and genetic synopsis. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1849:454-61. [PMID: 25088176 DOI: 10.1016/j.bbagrm.2014.07.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 07/25/2014] [Accepted: 07/28/2014] [Indexed: 12/24/2022]
Abstract
Injury is an inescapable phenomenon of life that affects animals at every physiological level. Yet, some animals respond to injury by rebuilding the damaged tissues whereas others are limited to scarring. Elucidating how a tissue insult from wounding leads to a regenerative response at the genetic level is essential to make regenerative advantages translational. It has become clear that animals with regenerative abilities recycle developmental programs after injury, reactivating genes that have lied dormant throughout adulthood. The question that is critical to our understanding of regeneration is how a specific set of developmentally important genes can be reactivated only after an acute tissue insult. Here, we review how injury-induced cellular stresses such as hypoxic, oxidative, and mechanical stress may contribute to the genomic and epigenetic changes that promote regeneration in animals. This article is part of a Special Issue entitled: Stress as a fundamental theme in cell plasticity.
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25
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Rao N, Song F, Jhamb D, Wang M, Milner DJ, Price NM, Belecky-Adams TL, Palakal MJ, Cameron JA, Li B, Chen X, Stocum DL. Proteomic analysis of fibroblastema formation in regenerating hind limbs of Xenopus laevis froglets and comparison to axolotl. BMC DEVELOPMENTAL BIOLOGY 2014; 14:32. [PMID: 25063185 PMCID: PMC4222900 DOI: 10.1186/1471-213x-14-32] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 07/03/2014] [Indexed: 01/01/2023]
Abstract
Background To gain insight into what differences might restrict the capacity for limb regeneration in Xenopus froglets, we used High Performance Liquid Chromatography (HPLC)/double mass spectrometry to characterize protein expression during fibroblastema formation in the amputated froglet hindlimb, and compared the results to those obtained previously for blastema formation in the axolotl limb. Results Comparison of the Xenopus fibroblastema and axolotl blastema revealed several similarities and significant differences in proteomic profiles. The most significant similarity was the strong parallel down regulation of muscle proteins and enzymes involved in carbohydrate metabolism. Regenerating Xenopus limbs differed significantly from axolotl regenerating limbs in several ways: deficiency in the inositol phosphate/diacylglycerol signaling pathway, down regulation of Wnt signaling, up regulation of extracellular matrix (ECM) proteins and proteins involved in chondrocyte differentiation, lack of expression of a key cell cycle protein, ecotropic viral integration site 5 (EVI5), that blocks mitosis in the axolotl, and the expression of several patterning proteins not seen in the axolotl that may dorsalize the fibroblastema. Conclusions We have characterized global protein expression during fibroblastema formation after amputation of the Xenopus froglet hindlimb and identified several differences that lead to signaling deficiency, failure to retard mitosis, premature chondrocyte differentiation, and failure of dorsoventral axial asymmetry. These differences point to possible interventions to improve blastema formation and pattern formation in the froglet limb.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - David L Stocum
- Department of Biology, and Center for Developmental and Regenerative Biology, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA.
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26
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Ratner BD. Going out on a limb about regrowing an arm. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2013; 24:2645-2649. [PMID: 24132739 DOI: 10.1007/s10856-013-5047-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2012] [Accepted: 08/30/2013] [Indexed: 06/02/2023]
Abstract
Starting with the observations that fetuses effortlessly grow limbs, fetuses heal wounds without scar and children up to the age of two can partially regrow amputated digits, the potential for adult humans to regrow limbs is explored. The process of limb growth in amphibians is reviewed with these steps summarizing the process: blood vessels contract to minimize bleeding; the injury site is covered by skin cells transforming into the apical epithelial cap which sends signals important for the next phases of the regrowth; resident fibroblasts leave the surrounding extracellular matrix and migrate across the amputation surface; migratory fibroblasts proliferate and dedifferentiate to form an aggregation of stemlike cells called the blastema; and the blastema coordinates the formation of a new limb. Other factors contributing to this process are: innervation, cell spatial "memory," chemical signals between cells, gene up and down regulation, cell differentiation (or dedifferentiation) and inflammatory cells. Remarkable discoveries have been made in all these areas in the last few years that might be integrated into technology for limb regeneration. In particular, the demonstration of the plasticity of supposedly "terminally differentiated" cells speak to the idea that mature cells at the amputation site might be harnessed for limb regrowth. Also, the demonstration that macrophages can be driven to a regenerative phenotype (M2) and they may also be stem-like is promising for complex regenerations. This article posits that scientific discoveries useful for limb regeneration have been made and now it is time to develop technology exploiting these discoveries to regrow limbs.
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Affiliation(s)
- Buddy D Ratner
- Departments of Bioengineering and Chemical Engineering, University of Washington Engineered Biomaterials (UWEB21), University of Washington, Seattle, WA, 98195, USA,
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Belan E. LINEs of evidence: noncanonical DNA replication as an epigenetic determinant. Biol Direct 2013; 8:22. [PMID: 24034780 PMCID: PMC3868326 DOI: 10.1186/1745-6150-8-22] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 09/06/2013] [Indexed: 12/17/2022] Open
Abstract
LINE-1 (L1) retrotransposons are repetitive elements in mammalian genomes. They are
capable of synthesizing DNA on their own RNA templates by harnessing reverse
transcriptase (RT) that they encode. Abundantly expressed full-length L1s and their
RT are found to globally influence gene expression profiles, differentiation state,
and proliferation capacity of early embryos and many types of cancer, albeit by yet
unknown mechanisms. They are essential for the progression of early development and
the establishment of a cancer-related undifferentiated state. This raises important
questions regarding the functional significance of L1 RT in these cell systems.
Massive nuclear L1-linked reverse transcription has been shown to occur in mouse
zygotes and two-cell embryos, and this phenomenon is purported to be DNA replication
independent. This review argues against this claim with the goal of understanding the
nature of this phenomenon and the role of L1 RT in early embryos and cancers.
Available L1 data are revisited and integrated with relevant findings accumulated in
the fields of replication timing, chromatin organization, and epigenetics, bringing
together evidence that strongly supports two new concepts. First, noncanonical
replication of a portion of genomic full-length L1s by means of L1 RNP-driven reverse
transcription is proposed to co-exist with DNA polymerase-dependent replication of
the rest of the genome during the same round of DNA replication in embryonic and
cancer cell systems. Second, the role of this mechanism is thought to be epigenetic;
it might promote transcriptional competence of neighboring genes linked to
undifferentiated states through the prevention of tethering of involved L1s to the
nuclear periphery. From the standpoint of these concepts, several hitherto
inexplicable phenomena can be explained. Testing methods for the model are
proposed.
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Affiliation(s)
- Ekaterina Belan
- Genetics Laboratory, Royal University Hospital, Saskatoon, SK S7N 0W8, Canada.
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Grafi G. Stress cycles in stem cells/iPSCs development: implications for tissue repair. Biogerontology 2013; 14:603-8. [PMID: 23852045 DOI: 10.1007/s10522-013-9445-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 07/07/2013] [Indexed: 12/12/2022]
Abstract
Stem cells have become a major topic, both publicly and scientifically, owing to their potential to cure diseases and repair damaged tissues. Particular attention has been given to the so-called "induced pluripotent stem cells" (iPSCs) in which somatic cells are induced by the expression of transcription factor encoding transgenes-a methodology first established by Takahashi and Yamanaka (Cell 126:663-676, 2006)-to acquire pluripotent state. This methodology has captured researchers' imagination as a potential procedure to obtain patient-specific therapies while also solving both the problem of transplant rejection and the ethical concerns often raised regarding the use of embryonic stem cells in regenerative medicine. The study of the biology of stem cells/iPSCs, in recent years, has uncovered some fundamental weaknesses that undermine their potential use in transplantation therapies.
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Affiliation(s)
- Gideon Grafi
- French Associates Institute for Agriculture and Biotechnology of Drylands, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, 84990, Midreshet Ben-Gurion, Israel,
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Stewart R, Rascón CA, Tian S, Nie J, Barry C, Chu LF, Ardalani H, Wagner RJ, Probasco MD, Bolin JM, Leng N, Sengupta S, Volkmer M, Habermann B, Tanaka EM, Thomson JA, Dewey CN. Comparative RNA-seq analysis in the unsequenced axolotl: the oncogene burst highlights early gene expression in the blastema. PLoS Comput Biol 2013; 9:e1002936. [PMID: 23505351 PMCID: PMC3591270 DOI: 10.1371/journal.pcbi.1002936] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Accepted: 01/08/2013] [Indexed: 01/09/2023] Open
Abstract
The salamander has the remarkable ability to regenerate its limb after amputation. Cells at the site of amputation form a blastema and then proliferate and differentiate to regrow the limb. To better understand this process, we performed deep RNA sequencing of the blastema over a time course in the axolotl, a species whose genome has not been sequenced. Using a novel comparative approach to analyzing RNA-seq data, we characterized the transcriptional dynamics of the regenerating axolotl limb with respect to the human gene set. This approach involved de novo assembly of axolotl transcripts, RNA-seq transcript quantification without a reference genome, and transformation of abundances from axolotl contigs to human genes. We found a prominent burst in oncogene expression during the first day and blastemal/limb bud genes peaking at 7 to 14 days. In addition, we found that limb patterning genes, SALL genes, and genes involved in angiogenesis, wound healing, defense/immunity, and bone development are enriched during blastema formation and development. Finally, we identified a category of genes with no prior literature support for limb regeneration that are candidates for further evaluation based on their expression pattern during the regenerative process.
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Affiliation(s)
- Ron Stewart
- Regenerative Biology, Morgridge Institute for Research, Madison, Wisconsin, United States of America.
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Abdullayev I, Kirkham M, Björklund ÅK, Simon A, Sandberg R. A reference transcriptome and inferred proteome for the salamander Notophthalmus viridescens. Exp Cell Res 2013; 319:1187-97. [PMID: 23454602 DOI: 10.1016/j.yexcr.2013.02.013] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 02/15/2013] [Accepted: 02/18/2013] [Indexed: 11/26/2022]
Abstract
Salamanders have a remarkable capacity to regenerate complex tissues, such as limbs and brain, and are therefore an important comparative model system for regenerative medicine. Despite these unique properties among adult vertebrates, the genomic information for amphibians in general, and salamanders in particular, is scarce. Here, we used massive parallel sequencing to reconstruct a de novo reference transcriptome of the red spotted newt (Notophthalmus viridescens) containing 118,893 transcripts with a N50 length of 2016 nts. Comparisons to other vertebrates revealed a newt transcriptome that is comparable in size and characteristics to well-annotated vertebrate transcriptomes. Identification of putative open reading frames (ORFs) enabled us to infer a comprehensive proteome, including the annotation of 19,903 newt proteins. We used the identified domain architectures (DAs) to assign ORFs phylogenetic positions, which also revealed putative salamander specific proteins. The reference transcriptome and inferred proteome of the red spotted newt will facilitate the use of systematic genomic technologies for regeneration studies in salamanders and enable evolutionary analyses of vertebrate regeneration at the molecular level.
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Affiliation(s)
- Ilgar Abdullayev
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
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