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James LM, Strickland Z, Lopez N, Whited JL, Maden M, Lewis J. Identification and Analysis of Axolotl Homologs for Proteins Implicated in Human Neurodegenerative Proteinopathies. Genes (Basel) 2024; 15:310. [PMID: 38540368 PMCID: PMC10969905 DOI: 10.3390/genes15030310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 02/22/2024] [Accepted: 02/24/2024] [Indexed: 06/14/2024] Open
Abstract
Neurodegenerative proteinopathies such as Alzheimer's Disease are characterized by abnormal protein aggregation and neurodegeneration. Neuroresilience or regenerative strategies to prevent neurodegeneration, preserve function, or restore lost neurons may have the potential to combat human proteinopathies; however, the adult human brain possesses a limited capacity to replace lost neurons. In contrast, axolotls (Ambystoma mexicanum) show robust brain regeneration. To determine whether axolotls may help identify potential neuroresilience or regenerative strategies in humans, we first interrogated whether axolotls express putative proteins homologous to human proteins associated with neurodegenerative diseases. We compared the homology between human and axolotl proteins implicated in human proteinopathies and found that axolotls encode proteins highly similar to human microtubule-binding protein tau (tau), amyloid precursor protein (APP), and β-secretase 1 (BACE1), which are critically involved in human proteinopathies like Alzheimer's Disease. We then tested monoclonal Tau and BACE1 antibodies previously used in human and rodent neurodegenerative disease studies using immunohistochemistry and western blotting to validate the homology for these proteins. These studies suggest that axolotls may prove useful in studying the role of these proteins in disease within the context of neuroresilience and repair.
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Affiliation(s)
- Lucas M. James
- Department of Neuroscience, University of Florida, Gainesville, FL 32610, USA; (L.M.J.); (Z.S.)
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Zachary Strickland
- Department of Neuroscience, University of Florida, Gainesville, FL 32610, USA; (L.M.J.); (Z.S.)
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Noah Lopez
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
- The Harvard Stem Cell Institute, Cambridge, MA 02138, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jessica L. Whited
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
- The Harvard Stem Cell Institute, Cambridge, MA 02138, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Malcolm Maden
- Department of Biology and UF Genetics Institute, University of Florida, Gainesville, FL 32611, USA
| | - Jada Lewis
- Department of Neuroscience, University of Florida, Gainesville, FL 32610, USA; (L.M.J.); (Z.S.)
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32610, USA
- Evelyn F. and William L. McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
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2
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Markitantova Y, Fokin A, Boguslavsky D, Simirskii V, Kulikov A. Molecular Signatures Integral to Natural Reprogramming in the Pigment Epithelium Cells after Retinal Detachment in Pleurodeles waltl. Int J Mol Sci 2023; 24:16940. [PMID: 38069262 PMCID: PMC10707686 DOI: 10.3390/ijms242316940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/20/2023] [Accepted: 11/21/2023] [Indexed: 12/18/2023] Open
Abstract
The reprogramming of retinal pigment epithelium (RPE) cells into retinal cells (transdifferentiation) lies in the bases of retinal regeneration in several Urodela. The identification of the key genes involved in this process helps with looking for approaches to the prevention and treatment of RPE-related degenerative diseases of the human retina. The purpose of our study was to examine the transcriptome changes at initial stages of RPE cell reprogramming in adult newt Pleurodeles waltl. RPE was isolated from the eye samples of day 0, 4, and 7 after experimental surgical detachment of the neural retina and was used for a de novo transcriptome assembly through the RNA-Seq method. A total of 1019 transcripts corresponding to the differently expressed genes have been revealed in silico: the 83 increased the expression at an early stage, and 168 increased the expression at a late stage of RPE reprogramming. We have identified up-regulation of classical early response genes, chaperones and co-chaperones, genes involved in the regulation of protein biosynthesis, suppressors of oncogenes, and EMT-related genes. We revealed the growth in the proportion of down-regulated ribosomal and translation-associated genes. Our findings contribute to revealing the molecular mechanism of RPE reprogramming in Urodela.
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Affiliation(s)
| | | | | | - Vladimir Simirskii
- Koltsov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia; (Y.M.); (A.K.)
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3
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Šimková K, Naraine R, Vintr J, Soukup V, Šindelka R. RNA localization during early development of the axolotl. Front Cell Dev Biol 2023; 11:1260795. [PMID: 37928901 PMCID: PMC10620976 DOI: 10.3389/fcell.2023.1260795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 09/26/2023] [Indexed: 11/07/2023] Open
Abstract
The asymmetric localization of biomolecules is critical for body plan development. One of the most popular model organisms for early embryogenesis studies is Xenopus laevis but there is a lack of information in other animal species. Here, we compared the early development of two amphibian species-the frog X. laevis and the axolotl Ambystoma mexicanum. This study aimed to identify asymmetrically localized RNAs along the animal-vegetal axis during the early development of A. mexicanum. For that purpose, we performed spatial transcriptome-wide analysis at low resolution, which revealed dynamic changes along the animal-vegetal axis classified into the following categories: profile alteration, de novo synthesis and degradation. Surprisingly, our results showed that many of the vegetally localized genes, which are important for germ cell development, are degraded during early development. Furthermore, we assessed the motif presence in UTRs of degraded mRNAs and revealed the enrichment of several motifs in RNAs of germ cell markers. Our results suggest novel reorganization of the transcriptome during embryogenesis of A. mexicanum to converge to the similar developmental pattern as the X. laevis.
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Affiliation(s)
- Kateřina Šimková
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
| | - Ravindra Naraine
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
| | - Jan Vintr
- Department of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Vladimír Soukup
- Department of Zoology, Faculty of Science, Charles University, Prague, Czechia
| | - Radek Šindelka
- Laboratory of Gene Expression, Institute of Biotechnology of the Czech Academy of Sciences, Vestec, Czechia
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4
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Sandoval-Guzmán T. The axolotl. Nat Methods 2023; 20:1117-1119. [PMID: 37553398 DOI: 10.1038/s41592-023-01961-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Affiliation(s)
- Tatiana Sandoval-Guzmán
- Department of Internal Medicine 3, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany.
- Paul Langerhans Institute Dresden of Helmholtz Centre Munich, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany.
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5
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Nowoshilow S, Tanaka EM. Navigation and Use of Custom Tracks within the Axolotl Genome Browser. Methods Mol Biol 2023; 2562:273-289. [PMID: 36272083 DOI: 10.1007/978-1-0716-2659-7_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The availability of the chromosome-scale axolotl genome sequences has made it possible to explore genome evolution, perform cross-species comparisons, and use additional sequencing data to analyze both genome-wide features and individual genes. Here, we will focus on the UCSC genome browser and demonstrate in a step-by-step manner how to use it to integrate different data to approach a broad question of the Fgf8 locus evolution and analyze the neighborhood of a gene that was reported missing in axolotl - Pax3.
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Affiliation(s)
| | - Elly M Tanaka
- Research Institute of Molecular Pathology, Vienna, Austria.
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6
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Masselink W, Sandoval-Guzmán T, Yun MH. Meeting report: Salamander Models in Cross-disciplinary Biological Research Meeting. Dev Dyn 2022; 251:906-910. [PMID: 35451159 DOI: 10.1002/dvdy.481] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 04/18/2022] [Indexed: 11/09/2022] Open
Abstract
The 3rd annual meeting on 'Salamander Models in Cross-disciplinary Biological Research' took place online on August 2021, bringing together over 200 international researchers using salamanders as research models and encompassing diverse fields, ranging from Development and Regeneration through to Immunology, Pathogenesis and Evolution. The event was organized by Maximina H. Yun (Center for Regenerative Therapies Dresden, Germany) and Tatiana Sandoval-Guzmán (TU Dresden, Germany) with the generous support of the Deutsche Forschungsgemeinschaft, the Center for Regenerative Therapies Dresden, Technische Universität Dresden, and the Company of Biologists. Showcasing a number of emerging salamander models, innovative techniques and resources, and providing a platform for sharing both published and ongoing research, this meeting proved to be an excellent forum for exchanging ideas and moving research forwards. Here, we discuss the highlights stemming from this exciting scientific event. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Wouter Masselink
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-BioCenter 1, 1030, Vienna, Austria
| | - Tatiana Sandoval-Guzmán
- Department of Internal Medicine 3, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany.,Paul Langerhans Institute Dresden of Helmholtz Centre Munich at University Clinic Carl Gustav Carus of TU Dresden Faculty of Medicine, Dresden, Germany
| | - Maximina H Yun
- Technische Universität Dresden, CRTD/Center for Regenerative Therapies Dresden, Germany.,Max Planck Institute for Molecular Cell Biology and Genetics, Dresden, Germany
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Abstract
The salamander Ambystoma mexicanum, commonly called "the axolotl" has a long, illustrious history as a model organism, perhaps with one of the longest track records as a laboratory-bred vertebrate, yet it also holds a prominent place among the emerging model organisms. Or rather it is by now an "emerged" model organism, boasting a full cohort molecular genetic tools that allows an expanding community of researchers in the field to explore the remarkable traits of this animal including regeneration, at cellular and molecular precision-which had been a dream for researchers over the years. This chapter describes the journey to this status, that could be helpful for those developing their respective animal or plant models.
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Affiliation(s)
- Karen Echeverri
- Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA, United States
| | - Jifeng Fei
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Elly M Tanaka
- Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria.
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8
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Al Haj Baddar N, Timoshevskaya N, Smith JJ, Guo H, Voss SR. Novel Expansion of Matrix Metalloproteases in the Laboratory Axolotl (Ambystoma mexicanum) and Other Salamander Species. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.786263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Matrix metalloprotease (MMP) genes encode endopeptidases that cleave protein components of the extracellular matrix (ECM) as well as non-ECM proteins. Here we report the results of a comprehensive survey of MMPs in the laboratory axolotl and other representative salamanders. Surprisingly, 28 MMPs were identified in salamanders and 9 MMP paralogs were identified as unique to the axolotl and other salamander taxa, with several of these presenting atypical amino acid insertions not observed in other tetrapod vertebrates. Furthermore, as assessed by sequence information, all of the novel salamander MMPs are of the secreted type, rather than cell membrane anchored. This suggests that secreted type MMPs expanded uniquely within salamanders to presumably execute catalytic activities in the extracellular milieu. To facilitate future studies of salamander-specific MMPs, we annotated transcriptional information from published studies of limb and tail regeneration. Our analysis sets the stage for comparative studies to understand why MMPs expanded uniquely within salamanders.
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McGinnity D, Reinsch SD, Schwartz H, Trudeau V, Browne RK. Semen and oocyte collection, sperm cryopreservation and IVF with the threatened North American giant salamander Cryptobranchus alleganiensis. Reprod Fertil Dev 2021; 34:470-477. [PMID: 34412770 DOI: 10.1071/rd21035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/27/2021] [Indexed: 11/23/2022] Open
Abstract
Semen of high to moderate quality was collected following the hormonal induction of North American giant salamanders Cryptobranchus alleganiensis. Oocytes from one female yielded the first C. alleganiensis produced while maintained in aquaria under human care and the first externally fertilising salamander produced with cryopreserved spermatozoa and IVF. Further research is needed with North American giant salamanders to establish reliable techniques to produce large numbers of viable offspring, along with the application of cryopreserved spermatozoa.
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Affiliation(s)
- Dale McGinnity
- Ectotherm Department, Nashville Zoo at Grassmere, 3777 Nolensville Rd, Nashville, TN 37211, USA; and Corresponding author
| | - Sherri D Reinsch
- Ectotherm Department, Nashville Zoo at Grassmere, 3777 Nolensville Rd, Nashville, TN 37211, USA
| | - Heather Schwartz
- Veterinary Department, Nashville Zoo at Grassmere, 3777 Nolensville Rd, Nashville, TN 37211, USA
| | - Vance Trudeau
- Department of Biology, University of Ottawa, 75 Laurier Ave East, Ottawa, ON, K1N 6N5, Canada
| | - Robert K Browne
- Sustainability America, La Isla Road, Sarteneja, Corozal District, Belize
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10
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Lumelsky N. Creating a Pro-Regenerative Tissue Microenvironment: Local Control is the Key. Front Bioeng Biotechnol 2021; 9:712685. [PMID: 34368106 PMCID: PMC8334550 DOI: 10.3389/fbioe.2021.712685] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/09/2021] [Indexed: 01/01/2023] Open
Affiliation(s)
- Nadya Lumelsky
- National Institute of Dental and Craniofacial Research (NIDCR), National Institutes of Health (NIH), Bethesda, MD, United States
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11
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Fibroblast dedifferentiation as a determinant of successful regeneration. Dev Cell 2021; 56:1541-1551.e6. [PMID: 34004152 PMCID: PMC8140481 DOI: 10.1016/j.devcel.2021.04.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 02/03/2021] [Accepted: 04/16/2021] [Indexed: 12/31/2022]
Abstract
Limb regeneration, while observed lifelong in salamanders, is restricted in post-metamorphic Xenopus laevis frogs. Whether this loss is due to systemic factors or an intrinsic incapability of cells to form competent stem cells has been unclear. Here, we use genetic fate mapping to establish that connective tissue (CT) cells form the post-metamorphic frog blastema, as in the case of axolotls. Using heterochronic transplantation into the limb bud and single-cell transcriptomic profiling, we show that axolotl CT cells dedifferentiate and integrate to form lineages, including cartilage. In contrast, frog blastema CT cells do not fully re-express the limb bud progenitor program, even when transplanted into the limb bud. Correspondingly, transplanted cells contribute to extraskeletal CT, but not to the developing cartilage. Furthermore, using single-cell RNA-seq analysis we find that embryonic and adult frog cartilage differentiation programs are molecularly distinct. This work defines intrinsic restrictions in CT dedifferentiation as a limitation in adult regeneration. Fibroblast-derived Prrx1+ cells are the main constituent of a frog limb blastema Frog fibroblasts only undergo partial dedifferentiation due to intrinsic limitations Adult chondrogenesis is distinct from the embryonic program
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The giant axolotl genome uncovers the evolution, scaling, and transcriptional control of complex gene loci. Proc Natl Acad Sci U S A 2021; 118:2017176118. [PMID: 33827918 PMCID: PMC8053990 DOI: 10.1073/pnas.2017176118] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The axolotl is an important model organism because it is a tetrapod with a similar body plan to humans. Unlike humans, the axolotl regenerates limbs and other complex tissues. Therefore, the axolotl contributes to understanding evolution, development, and regeneration. With sophisticated tools for gene modification and tissue labeling, a fully assembled genome sequence was a sorely missing resource. Assembly was difficult because the genome size is 10× that of humans. Here, we use a cross-linking strategy called Hi-C to link together fragmented genome sequences to chromosome scale. We show that gene regulation occurs over very large genomic distances and that mitotic chromosomes are packaged efficiently. Vertebrates harbor recognizably orthologous gene complements but vary 100-fold in genome size. How chromosomal organization scales with genome expansion is unclear, and how acute changes in gene regulation, as during axolotl limb regeneration, occur in the context of a vast genome has remained a riddle. Here, we describe the chromosome-scale assembly of the giant, 32 Gb axolotl genome. Hi-C contact data revealed the scaling properties of interphase and mitotic chromosome organization. Analysis of the assembly yielded understanding of the evolution of large, syntenic multigene clusters, including the Major Histocompatibility Complex (MHC) and the functional regulatory landscape of the Fibroblast Growth Factor 8 (Axfgf8) region. The axolotl serves as a primary model for studying successful regeneration.
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Debuque RJ, Nowoshilow S, Chan KE, Rosenthal NA, Godwin JW. Distinct toll-like receptor signaling in the salamander response to tissue damage. Dev Dyn 2021; 251:988-1003. [PMID: 33797128 DOI: 10.1002/dvdy.340] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/10/2021] [Accepted: 03/29/2021] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Efficient wound healing or pathogen clearance both rely on balanced inflammatory responses. Inflammation is essential for effective innate immune-cell recruitment; however, excessive inflammation will result in local tissue destruction, pathogen egress, and ineffective pathogen clearance. Sterile and nonsterile inflammation operate with competing functional priorities but share common receptors and overlapping signal transduction pathways. In regenerative organisms such as the salamander, whole limbs can be replaced after amputation while exposed to a nonsterile environment. In mammals, exposure to sterile-injury Damage Associated Molecular Patterns (DAMPS) alters innate immune-cell responsiveness to secondary Pathogen Associated Molecular Pattern (PAMP) exposure. RESULTS Using new phospho-flow cytometry techniques to measure signaling in individual cell subsets we compared mouse to salamander inflammation. These studies demonstrated evolutionarily conserved responses to PAMP ligands through toll-like receptors (TLRs) but identified key differences in response to DAMP ligands. Co-exposure of macrophages to DAMPs/PAMPs suppressed MAPK signaling in mammals, but not salamanders, which activate sustained MAPK stimulation in the presence of endogenous DAMPS. CONCLUSIONS These results reveal an alternative signal transduction network compatible with regeneration that may ultimately lead to the promotion of enhanced tissue repair in mammals.
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Affiliation(s)
- Ryan J Debuque
- Australian Regenerative Medicine Institute (ARMI), Monash University, Melbourne, Victoria, Australia
| | - Sergej Nowoshilow
- The Research Institute of Molecular Pathology (IMP), Vienna, Austria
| | | | | | - James W Godwin
- Australian Regenerative Medicine Institute (ARMI), Monash University, Melbourne, Victoria, Australia.,The Jackson Laboratory, Bar Harbour, Maine, USA.,The MDI Biological Laboratory (MDIBL), Salisbury Cove, Maine, USA
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14
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Meyer A, Schloissnig S, Franchini P, Du K, Woltering JM, Irisarri I, Wong WY, Nowoshilow S, Kneitz S, Kawaguchi A, Fabrizius A, Xiong P, Dechaud C, Spaink HP, Volff JN, Simakov O, Burmester T, Tanaka EM, Schartl M. Giant lungfish genome elucidates the conquest of land by vertebrates. Nature 2021; 590:284-289. [PMID: 33461212 PMCID: PMC7875771 DOI: 10.1038/s41586-021-03198-8] [Citation(s) in RCA: 95] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 01/06/2021] [Indexed: 01/29/2023]
Abstract
Lungfishes belong to lobe-fined fish (Sarcopterygii) that, in the Devonian period, 'conquered' the land and ultimately gave rise to all land vertebrates, including humans1-3. Here we determine the chromosome-quality genome of the Australian lungfish (Neoceratodus forsteri), which is known to have the largest genome of any animal. The vast size of this genome, which is about 14× larger than that of humans, is attributable mostly to huge intergenic regions and introns with high repeat content (around 90%), the components of which resemble those of tetrapods (comprising mainly long interspersed nuclear elements) more than they do those of ray-finned fish. The lungfish genome continues to expand independently (its transposable elements are still active), through mechanisms different to those of the enormous genomes of salamanders. The 17 fully assembled lungfish macrochromosomes maintain synteny to other vertebrate chromosomes, and all microchromosomes maintain conserved ancient homology with the ancestral vertebrate karyotype. Our phylogenomic analyses confirm previous reports that lungfish occupy a key evolutionary position as the closest living relatives to tetrapods4,5, underscoring the importance of lungfish for understanding innovations associated with terrestrialization. Lungfish preadaptations to living on land include the gain of limb-like expression in developmental genes such as hoxc13 and sall1 in their lobed fins. Increased rates of evolution and the duplication of genes associated with obligate air-breathing, such as lung surfactants and the expansion of odorant receptor gene families (which encode proteins involved in detecting airborne odours), contribute to the tetrapod-like biology of lungfishes. These findings advance our understanding of this major transition during vertebrate evolution.
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Affiliation(s)
- Axel Meyer
- Department of Biology, University of Konstanz, Konstanz, Germany.
| | | | - Paolo Franchini
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Kang Du
- Developmental Biochemistry, Biocenter, University of Würzburg, Würzburg, Germany
- The Xiphophorus Genetic Stock Center, Texas State University, San Marcos, TX, USA
| | | | - Iker Irisarri
- Department of Biodiversity and Evolutionary Biology, Museo Nacional de Ciencias Naturales (MNCN-CSIC), Madrid, Spain
- Department of Applied Bioinformatics, Institute for Microbiology and Genetics, University of Goettingen, Goettingen, Germany
| | - Wai Yee Wong
- Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria
| | | | - Susanne Kneitz
- Biochemistry and Cell Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Akane Kawaguchi
- Research Institute of Molecular Pathology (IMP), Vienna, Austria
| | | | - Peiwen Xiong
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Corentin Dechaud
- Institut de Génomique Fonctionnelle, École Normale Superieure, Université Claude Bernard, Lyon, France
| | - Herman P Spaink
- Faculty of Science, Universiteit Leiden, Leiden, The Netherlands
| | - Jean-Nicolas Volff
- Institut de Génomique Fonctionnelle, École Normale Superieure, Université Claude Bernard, Lyon, France
| | - Oleg Simakov
- Department of Neuroscience and Developmental Biology, University of Vienna, Vienna, Austria.
| | | | - Elly M Tanaka
- Research Institute of Molecular Pathology (IMP), Vienna, Austria.
| | - Manfred Schartl
- Developmental Biochemistry, Biocenter, University of Würzburg, Würzburg, Germany.
- The Xiphophorus Genetic Stock Center, Texas State University, San Marcos, TX, USA.
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