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Qu X, Yang R, Tan C, Chen H, Wang X. Astrocytes-Secreted WNT5B Disrupts the Blood-Brain Barrier Via ROR1/JNK/c-JUN Cascade During Meningitic Escherichia Coli Infection. Mol Neurobiol 2024:10.1007/s12035-024-04303-4. [PMID: 38896157 DOI: 10.1007/s12035-024-04303-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 06/12/2024] [Indexed: 06/21/2024]
Abstract
The blood-brain barrier (BBB) is a complex structure that separates the central nervous system (CNS) from the peripheral blood circulation. Effective communication between different cell types within the BBB is crucial for its proper functioning and maintenance of homeostasis. In this study, we demonstrate that meningitic Escherichia coli (E. coli)-induced WNT5B plays a role in facilitating intercellular communication between astrocytes and brain microvascular endothelial cells (BMECs). We discovered that astrocytes-derived WNT5B activates the non-canonical WNT signaling pathway JNK/c-JUN in BMECs through its receptor ROR1, leading to inhibition of ZO-1 expression and impairment of the tight junction integrity in BMECs. Notably, our findings reveal that c-JUN, a transcription factor, directly regulates ZO-1 expression. By employing a dual luciferase reporting system and chromatin immunoprecipitation techniques, we identified specific binding sites of c-JUN on the ZO-1 promoter region. Overall, our study highlights the involvement of WNT5B in mediating intercellular communication between astrocytes and BMECs, provides insights into the role of WNT5B in meningitic E. coli-induced disruption of BBB integrity, and suggests potential therapeutic targeting of WNT5B as a strategy to address BBB dysfunction.
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Affiliation(s)
- Xinyi Qu
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Ruicheng Yang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
| | - Chen Tan
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
- Engineering Research Center of Animal Biopharmaceuticals, The Ministry of Education of the People's Republic of China (MOE), Wuhan, 430070, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, 430070, China
| | - Huanchun Chen
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China
- Engineering Research Center of Animal Biopharmaceuticals, The Ministry of Education of the People's Republic of China (MOE), Wuhan, 430070, China
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, 430070, China
| | - Xiangru Wang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.
- Key Laboratory of Preventive Veterinary Medicine in Hubei Province, The Cooperative Innovation Center for Sustainable Pig Production, Wuhan, 430070, China.
- Engineering Research Center of Animal Biopharmaceuticals, The Ministry of Education of the People's Republic of China (MOE), Wuhan, 430070, China.
- Frontiers Science Center for Animal Breeding and Sustainable Production, Wuhan, 430070, China.
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2
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Riquelme-Guzmán C, Sandoval-Guzmán T. The salamander limb: a perfect model to understand imperfect integration during skeletal regeneration. Biol Open 2024; 13:bio060152. [PMID: 38319134 PMCID: PMC10868587 DOI: 10.1242/bio.060152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024] Open
Abstract
Limb regeneration in salamanders is achieved by a complex coordination of various biological processes and requires the proper integration of new tissue with old. Among the tissues found inside the limb, the skeleton is the most prominent component, which serves as a scaffold and provides support for locomotion in the animal. Throughout the years, researchers have studied the regeneration of the appendicular skeleton in salamanders both after limb amputation and as a result of fracture healing. The final outcome has been widely seen as a faithful re-establishment of the skeletal elements, characterised by a seamless integration into the mature tissue. The process of skeletal integration, however, is not well understood, and several works have recently provided evidence of commonly occurring flawed regenerates. In this Review, we take the reader on a journey through the course of bone formation and regeneration in salamanders, laying down a foundation for critically examining the mechanisms behind skeletal integration. Integration is a phenomenon that could be influenced at various steps of regeneration, and hence, we assess the current knowledge in the field and discuss how early events, such as tissue histolysis and patterning, influence the faithful regeneration of the appendicular skeleton.
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Affiliation(s)
- Camilo Riquelme-Guzmán
- Department of Internal Medicine 3, Center for Healthy Aging, University Hospital Carl Gustav Carus at the Technische Universität Dresden, 01307 Dresden, Germany
| | - Tatiana Sandoval-Guzmán
- Department of Internal Medicine 3, Center for Healthy Aging, University Hospital Carl Gustav Carus at the Technische Universität Dresden, 01307 Dresden, Germany
- Paul Langerhans Institute Dresden of Helmholtz Centre Munich, University Hospital Carl Gustav Carus at the Technische Universität Dresden, 01307 Dresden, Germany
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3
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Tajer B, Savage AM, Whited JL. The salamander blastema within the broader context of metazoan regeneration. Front Cell Dev Biol 2023; 11:1206157. [PMID: 37635872 PMCID: PMC10450636 DOI: 10.3389/fcell.2023.1206157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 07/26/2023] [Indexed: 08/29/2023] Open
Abstract
Throughout the animal kingdom regenerative ability varies greatly from species to species, and even tissue to tissue within the same organism. The sheer diversity of structures and mechanisms renders a thorough comparison of molecular processes truly daunting. Are "blastemas" found in organisms as distantly related as planarians and axolotls derived from the same ancestral process, or did they arise convergently and independently? Is a mouse digit tip blastema orthologous to a salamander limb blastema? In other fields, the thorough characterization of a reference model has greatly facilitated these comparisons. For example, the amphibian Spemann-Mangold organizer has served as an amazingly useful comparative template within the field of developmental biology, allowing researchers to draw analogies between distantly related species, and developmental processes which are superficially quite different. The salamander limb blastema may serve as the best starting point for a comparative analysis of regeneration, as it has been characterized by over 200 years of research and is supported by a growing arsenal of molecular tools. The anatomical and evolutionary closeness of the salamander and human limb also add value from a translational and therapeutic standpoint. Tracing the evolutionary origins of the salamander blastema, and its relatedness to other regenerative processes throughout the animal kingdom, will both enhance our basic biological understanding of regeneration and inform our selection of regenerative model systems.
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Affiliation(s)
| | | | - Jessica L. Whited
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, United States
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4
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Min S, Whited JL. Limb blastema formation: How much do we know at a genetic and epigenetic level? J Biol Chem 2023; 299:102858. [PMID: 36596359 PMCID: PMC9898764 DOI: 10.1016/j.jbc.2022.102858] [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: 12/22/2021] [Revised: 12/13/2022] [Accepted: 12/23/2022] [Indexed: 01/02/2023] Open
Abstract
Regeneration of missing body parts is an incredible ability which is present in a wide number of species. However, this regenerative capability varies among different organisms. Urodeles (salamanders) are able to completely regenerate limbs after amputation through the essential process of blastema formation. The blastema is a collection of relatively undifferentiated progenitor cells that proliferate and repattern to form the internal tissues of a regenerated limb. Understanding blastema formation in salamanders may enable comparative studies with other animals, including mammals, with more limited regenerative abilities and may inspire future therapeutic approaches in humans. This review focuses on the current state of knowledge about how limb blastemas form in salamanders, highlighting both the possible roles of epigenetic controls in this process as well as limitations to scientific understanding that present opportunities for research.
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Affiliation(s)
- Sangwon Min
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Jessica L Whited
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, USA.
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5
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Purushothaman S, Seifert AW. Whole-Mount In Situ Hybridization (WISH) for Salamander Embryos and Larvae. Methods Mol Biol 2023; 2562:95-107. [PMID: 36272069 DOI: 10.1007/978-1-0716-2659-7_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Whole-mount in situ hybridization (WISH) is widely used to visualize transcribed gene sequences (mRNA) in developing embryos, larvae, and other nucleotide probe permeable tissue samples. This methodology involves the hybridization of an antisense nucleotide probe to the target mRNA, followed by chromogen or fluorescence-based detection. Here we describe a protocol for the spatiotemporal analysis of mRNA transcripts in axolotl embryos/larvae using digoxigenin-labeled riboprobes, anti-digoxigenin alkaline phosphatase, Fab fragments antibody, and NBT/BCIP chromogen detection.
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Affiliation(s)
| | - Ashley W Seifert
- Department of Biology, University of Kentucky, Lexington, KY, USA.
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6
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Johnson GL, Glasser MB, Charles JF, Duryea J, Lehoczky JA. En1 and Lmx1b do not recapitulate embryonic dorsal-ventral limb patterning functions during mouse digit tip regeneration. Cell Rep 2022; 41:111701. [PMID: 36417876 PMCID: PMC9727699 DOI: 10.1016/j.celrep.2022.111701] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 09/09/2022] [Accepted: 10/31/2022] [Indexed: 11/23/2022] Open
Abstract
The mouse digit tip regenerates following amputation. How the regenerate is patterned is unknown, but a long-standing hypothesis proposes developmental patterning mechanisms are re-used during regeneration. The digit tip bone exhibits dorsal-ventral (DV) polarity, so we focus on En1 and Lmx1b, two factors necessary for DV patterning during limb development. We investigate whether they are re-expressed during regeneration in a developmental-like pattern and whether they direct DV morphology of the regenerate. We find that both En1 and Lmx1b are expressed in the regenerating digit tip epithelium and mesenchyme, respectively, but without DV polarity. Conditional genetics and quantitative analysis of digit tip bone morphology determine that genetic deletion of En1 or Lmx1b in adult digit tip regeneration modestly reduces bone regeneration but does not affect DV patterning. Collectively, our data suggest that, while En1 and Lmx1b are re-expressed during mouse digit tip regeneration, they do not define the DV axis during regeneration.
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Affiliation(s)
- Gemma L. Johnson
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Morgan B. Glasser
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Julia F. Charles
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Department of Medicine, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Jeffrey Duryea
- Department of Radiology, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Jessica A. Lehoczky
- Department of Orthopedic Surgery, Brigham and Women’s Hospital, Boston, MA 02115, USA,Lead contact,Correspondence:
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7
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Wang M, Ge J, Ma X, Su S, Tian C, Li J, Yu F, Li H, Song C, Gao J, Xu P, Tang Y, Xu G. Exploration of the regulatory mechanisms of regeneration, anti-oxidation, anti-aging and the immune response at the post-molt stage of Eriocheir sinensis. Front Physiol 2022; 13:948511. [PMID: 36237529 PMCID: PMC9552667 DOI: 10.3389/fphys.2022.948511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/22/2022] [Indexed: 12/03/2022] Open
Abstract
Eriocheir sinensis is widely appreciated by the surrounding population due to its culinary delicacy and rich nutrients. The E. sinensis breeding industry is very prosperous and molting is one of the important growth characteristics. Research on the regulation of molting in E. sinensis is still in the initial stages. There is currently no relevant information on the regulatory mechanisms of heart development following molting. Comparative transcriptome analysis was used to study developmental regulation mechanisms in the heart of E. sinensis at the post-molt and inter-molt stages. The results indicated that many regulatory pathways and genes involved in regeneration, anti-oxidation, anti-aging and the immune response were significantly upregulated after molting in E. sinensis. Aside from cardiac development, the differentially expressed genes (DEGs) were relevant to myocardial movement and neuronal signal transduction. DEGs were also related to the regulation of glutathione homeostasis and biological rhythms in regard to anti-oxidation and anti-aging, and to the regulation of immune cell development and the immune response. This study provides a theoretical framework for understanding the regulation of molting in E. sinensis and in other economically important crustaceans.
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Affiliation(s)
- Meiyao Wang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Jiachun Ge
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, China
| | - Xingkong Ma
- Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing, China
| | - Shengyan Su
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Can Tian
- College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Jianlin Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Fan Yu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Hongxia Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Changyou Song
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Jiancao Gao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Pao Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Yongkai Tang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
- *Correspondence: Yongkai Tang, ; Gangchun Xu,
| | - Gangchun Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
- *Correspondence: Yongkai Tang, ; Gangchun Xu,
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8
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Yanagi N, Kato S, Fukazawa T, Kubo T. Cellular responses in the FGF10-mediated improvement of hindlimb regenerative capacity in Xenopus laevis revealed by single-cell transcriptomics. Dev Growth Differ 2022; 64:266-278. [PMID: 35642106 DOI: 10.1111/dgd.12795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/16/2022] [Accepted: 05/24/2022] [Indexed: 12/28/2022]
Abstract
Xenopus laevis tadpoles possess regenerative capacity in their hindlimb buds at early developmental stages (stages ~52-54); they can regenerate complete hindlimbs with digits after limb bud amputation. However, they gradually lose their regenerative capacity as metamorphosis proceeds. Tadpoles in late developmental stages regenerate fewer digits (stage ~56), or only form cartilaginous spike without digits or joints (stage ~58 or later) after amputation. Previous studies have shown that administration of fibroblast growth factor 10 (FGF10) in late-stage (stage 56) tadpole hindlimb buds after amputation can improve their regenerative capacity, which means that the cells responding to FGF10 signaling play an important role in limb bud regeneration. In this study, we performed single-cell RNA sequencing (scRNA-seq) of hindlimb buds that were amputated and administered FGF10 by implanting FGF10-soaked beads at a late stage (stage 56), and explored cell clusters exhibiting a differential gene expression pattern compared with that in controls treated with phosphate-buffered saline. The scRNA-seq data showed expansion of fgf8-expressing cells in the cluster of the apical epidermal cap of FGF10-treated hindlimb buds, which was reported previously, indicating that the administration of FGF10 was successful. On analysis, in addition to the epidermal cluster, a subset of myeloid cells and a newly identified cluster of steap4-expressing cells showed remarkable differences in their gene expression profiles between the FGF10- or phosphate-buffered saline-treatment conditions, suggesting a possible role of these clusters in improving the regenerative capacity of hindlimbs via FGF10 administration.
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Affiliation(s)
- Nodoka Yanagi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Sumika Kato
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Taro Fukazawa
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Takeo Kubo
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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9
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Lovely AM, Duerr TJ, Qiu Q, Galvan S, Voss SR, Monaghan JR. Wnt Signaling Coordinates the Expression of Limb Patterning Genes During Axolotl Forelimb Development and Regeneration. Front Cell Dev Biol 2022; 10:814250. [PMID: 35531102 PMCID: PMC9068880 DOI: 10.3389/fcell.2022.814250] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 03/21/2022] [Indexed: 11/13/2022] Open
Abstract
After amputation, axolotl salamanders can regenerate their limbs, but the degree to which limb regeneration recapitulates limb development remains unclear. One limitation in answering this question is our lack of knowledge about salamander limb development. Here, we address this question by studying expression patterns of genes important for limb patterning during axolotl salamander limb development and regeneration. We focus on the Wnt signaling pathway because it regulates multiple functions during tetrapod limb development, including limb bud initiation, outgrowth, patterning, and skeletal differentiation. We use fluorescence in situ hybridization to show the expression of Wnt ligands, Wnt receptors, and limb patterning genes in developing and regenerating limbs. Inhibition of Wnt ligand secretion permanently blocks limb bud outgrowth when treated early in limb development. Inhibiting Wnt signaling during limb outgrowth decreases the expression of critical signaling genes, including Fgf10, Fgf8, and Shh, leading to the reduced outgrowth of the limb. Patterns of gene expression are similar between developing and regenerating limbs. Inhibition of Wnt signaling during regeneration impacted patterning gene expression similarly. Overall, our findings suggest that limb development and regeneration utilize Wnt signaling similarly. It also provides new insights into the interaction of Wnt signaling with other signaling pathways during salamander limb development and regeneration.
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Affiliation(s)
| | - Timothy J. Duerr
- Department of Biology, Northeastern University, Boston, MA, United States
| | - Qingchao Qiu
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, and Ambystoma Genetic Stock Center, University of Kentucky, Lexington, KY, United States
| | | | - S. Randal Voss
- Department of Neuroscience, Spinal Cord and Brain Injury Research Center, and Ambystoma Genetic Stock Center, University of Kentucky, Lexington, KY, United States
| | - James R. Monaghan
- Department of Biology, Northeastern University, Boston, MA, United States
- Institute for Chemical Imaging of Living Systems, Northeastern University, Boston, MA, United States
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10
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Walker SE, Sabin KZ, Gearhart MD, Yamamoto K, Echeverri K. Regulation of stem cell identity by miR-200a during spinal cord regeneration. Development 2022; 149:274347. [PMID: 35156681 PMCID: PMC8918811 DOI: 10.1242/dev.200033] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 01/05/2022] [Indexed: 01/04/2023]
Abstract
Axolotls are an important model organism for multiple types of regeneration, including functional spinal cord regeneration. Remarkably, axolotls can repair their spinal cord after a small lesion injury and can also regenerate their entire tail following amputation. Several classical signaling pathways that are used during development are reactivated during regeneration, but how this is regulated remains a mystery. We have previously identified miR-200a as a key factor that promotes successful spinal cord regeneration. Here, using RNA-seq analysis, we discovered that the inhibition of miR-200a results in an upregulation of the classical mesodermal marker brachyury in spinal cord cells after injury. However, these cells still express the neural stem cell marker sox2. In vivo cell tracking allowed us to determine that these cells can give rise to cells of both the neural and mesoderm lineage. Additionally, we found that miR-200a can directly regulate brachyury via a seed sequence in the 3′UTR of the gene. Our data indicate that miR-200a represses mesodermal cell fate after a small lesion injury in the spinal cord when only glial cells and neurons need to be replaced. Summary: Axolotl spinal cord cells have the potential to form cells of the ectoderm and mesoderm depending on the extent of the injury they are responding to.
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Affiliation(s)
- Sarah E Walker
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | - Keith Z Sabin
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543, USA
| | | | | | - Karen Echeverri
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543, USA
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11
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Aztekin C. Tissues and Cell Types of Appendage Regeneration: A Detailed Look at the Wound Epidermis and Its Specialized Forms. Front Physiol 2021; 12:771040. [PMID: 34887777 PMCID: PMC8649801 DOI: 10.3389/fphys.2021.771040] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 10/25/2021] [Indexed: 11/13/2022] Open
Abstract
Therapeutic implementation of human limb regeneration is a daring aim. Studying species that can regrow their lost appendages provides clues on how such a feat can be achieved in mammals. One of the unique features of regeneration-competent species lies in their ability to seal the amputation plane with a scar-free wound epithelium. Subsequently, this wound epithelium advances and becomes a specialized wound epidermis (WE) which is hypothesized to be the essential component of regenerative success. Recently, the WE and specialized WE terminologies have been used interchangeably. However, these tissues were historically separated, and contemporary limb regeneration studies have provided critical new information which allows us to distinguish them. Here, I will summarize tissue-level observations and recently identified cell types of WE and their specialized forms in different regeneration models.
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Affiliation(s)
- Can Aztekin
- Swiss Federal Institute of Technology Lausanne, EPFL, School of Life Sciences, Lausanne, Switzerland
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12
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Hincapie Agudelo M, Carbonell Medina BA, Arenas Gómez CM, Delgado JP. Ambystoma mexicanum, a model organism in developmental biology and regeneration: a colombian experience. ACTA BIOLÓGICA COLOMBIANA 2021. [DOI: 10.15446/abc.v27n1.88309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Ambystoma mexicanum is a urodele amphibian endemic to Xochimilco Lake in Mexico, it belongs to the salamander family Ambystomatidae. This species has frequently been used as model organism in developmental biology and regeneration laboratories around the world due to its broad regenerative capacities and adaptability to laboratory conditions. In this review we describe the establishment of the first colony of axolotls in Colombia to study tissue regeneration and our perspectives on the use A. mexicanum as a model organism in Colombia are discussed emphasizing its possible uses in regeneration and developmental biology
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13
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Bassat E, Tanaka EM. The cellular and signaling dynamics of salamander limb regeneration. Curr Opin Cell Biol 2021; 73:117-123. [PMID: 34521022 DOI: 10.1016/j.ceb.2021.07.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/19/2021] [Accepted: 07/27/2021] [Indexed: 12/16/2022]
Abstract
Limb amputation in salamanders yields a wound response that ultimately leads to replacement of the missing part. This unique-among-tetrapod trait involves the migration and recruitment of multiple cell types including epithelium, immune cells, axonal growth cones, and connective tissue cells to build the blastema which contains the proliferating stem and progenitor cells to rebuild the limb tissues. A number of the signaling and cell biological events have been defined. They point to the intimate coordination of physical events such as osmotic pressure, cell migration, and cell-cell communication with changes in cell identity such as dedifferentiation into embryonic-like epithelial and mesenchymal cells.
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Affiliation(s)
- Elad Bassat
- Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus Vienna Biocenter, 1030, Vienna, Austria
| | - Elly M Tanaka
- Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus Vienna Biocenter, 1030, Vienna, Austria.
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14
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Expression of Wnt and TGF-Beta Pathway Components during Whole-Body Regeneration from Cell Aggregates in Demosponge Halisarca dujardinii. Genes (Basel) 2021; 12:genes12060944. [PMID: 34203064 PMCID: PMC8235796 DOI: 10.3390/genes12060944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 06/10/2021] [Accepted: 06/18/2021] [Indexed: 12/30/2022] Open
Abstract
The phenomenon of whole-body regeneration means rebuilding of the whole body of an animal from a small fragment or even a group of cells. In this process, the old axial relationships are often lost, and new ones are established. An amazing model for studying this process is sponges, some of which are able to regenerate into a definitive organism after dissociation into cells. We hypothesized that during the development of cell aggregates, primmorphs, new axes are established due to the activation of the Wnt and TGF-beta signaling pathways. Using in silico analysis, RNA-seq, and whole-mount in situ hybridization, we identified the participants in these signaling pathways and determined the spatiotemporal changes in their expression in demosponge Halisarca dujardinii. It was shown that Wnt and TGF-beta ligands are differentially expressed during primmorph development, and transcripts of several genes are localized at the poles of primmorphs, in the form of a gradient. We suppose that the Wnt and TGF-beta signaling cascades are involved in the initial axial patterning of the sponge body, which develops from cells after dissociation.
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Aztekin C, Hiscock TW, Gurdon J, Jullien J, Marioni J, Simons BD. Secreted inhibitors drive the loss of regeneration competence in Xenopus limbs. Development 2021; 148:269060. [PMID: 34105722 PMCID: PMC8217717 DOI: 10.1242/dev.199158] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 05/05/2021] [Indexed: 12/18/2022]
Abstract
Absence of a specialized wound epidermis is hypothesized to block limb regeneration in higher vertebrates. However, the factors preventing its formation in regeneration-incompetent animals are poorly understood. To characterize the endogenous molecular and cellular regulators of specialized wound epidermis formation in Xenopus laevis tadpoles, and the loss of their regeneration competency during development, we used single-cell transcriptomics and ex vivo regenerating limb cultures. Transcriptomic analysis revealed that the specialized wound epidermis is not a novel cell state, but a re-deployment of the apical-ectodermal-ridge (AER) programme underlying limb development. Enrichment of secreted inhibitory factors, including Noggin, a morphogen expressed in developing cartilage/bone progenitor cells, are identified as key inhibitors of AER cell formation in regeneration-incompetent tadpoles. These factors can be overridden by Fgf10, which operates upstream of Noggin and blocks chondrogenesis. These results indicate that manipulation of the extracellular environment and/or chondrogenesis may provide a strategy to restore regeneration potential in higher vertebrates. Summary: Secreted inhibitors associated with chondrogenic progression inhibit AER cell formation and restrict limb regeneration potential.
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Affiliation(s)
- Can Aztekin
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.,Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Tom W Hiscock
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.,Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, UK.,Institute of Medical Sciences, Foresterhill Health Campus, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - John Gurdon
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.,Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK
| | - Jerome Jullien
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.,Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, UK.,Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, F-44000 Nantes, France
| | - John Marioni
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, UK.,EMBL-European Bioinformatics Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK.,Wellcome Sanger Institute, Wellcome Genome Campus, Cambridge CB10 1SA, UK
| | - Benjamin David Simons
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK.,Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Cambridge CB3 0WA, UK.,Wellcome Trust Centre for Stem Cell Research, University of Cambridge, Cambridge CB2 0AW, UK
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16
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Safian D, Wiegertjes GF, Pollux BJA. The Fish Family Poeciliidae as a Model to Study the Evolution and Diversification of Regenerative Capacity in Vertebrates. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.613157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The capacity of regenerating a new structure after losing an old one is a major challenge in the animal kingdom. Fish have emerged as an interesting model to study regeneration due to their high and diverse regenerative capacity. To date, most efforts have focused on revealing the mechanisms underlying fin regeneration, but information on why and how this capacity evolves remains incomplete. Here, we propose the livebearing fish family Poeciliidae as a promising new model system to study the evolution of fin regeneration. First, we review the current state of knowledge on the evolution of regeneration in the animal kingdom, with a special emphasis on fish fins. Second, we summarize recent advances in our understanding of the mechanisms behind fin regeneration in fish. Third, we discuss potential evolutionary pressures that may modulate the regenerative capacity of fish fins and propose three new theories for how natural and sexual selection can lead to the evolution of fin regeneration: (1) signaling-driven fin regeneration, (2) predation-driven fin regeneration, and (3) matrotrophy-suppressed fin regeneration. Finally, we argue that fish from the family Poeciliidae are an excellent model system to test these theories, because they comprise of a large variety of species in a well-defined phylogenetic framework that inhabit very different environments and display remarkable variation in reproductive traits, allowing for comparative studies of fin regeneration among closely related species, among populations within species or among individuals within populations. This new model system has the potential to shed new light on the underlying genetic and molecular mechanisms driving the evolution and diversification of regeneration in vertebrates.
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17
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Elchaninov A, Sukhikh G, Fatkhudinov T. Evolution of Regeneration in Animals: A Tangled Story. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.621686] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The evolution of regenerative capacity in multicellular animals represents one of the most complex and intriguing problems in biology. How could such a seemingly advantageous trait as self-repair become consistently attenuated by the evolution? This review article examines the concept of the origin and nature of regeneration, its connection with the processes of embryonic development and asexual reproduction, as well as with the mechanisms of tissue homeostasis. The article presents a variety of classical and modern hypotheses explaining different trends in the evolution of regenerative capacity which is not always beneficial for the individual and notably for the species. Mechanistically, these trends are driven by the evolution of signaling pathways and progressive restriction of differentiation plasticity with concomitant advances in adaptive immunity. Examples of phylogenetically enhanced regenerative capacity are considered as well, with appropriate evolutionary reasoning for the enhancement and discussion of its molecular mechanisms.
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18
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Khan PA, Crawford MJ. Regeneration and development. An amphibian call to arms. Dev Dyn 2020; 250:896-901. [DOI: 10.1002/dvdy.272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 01/22/2023] Open
Affiliation(s)
- Paul A. Khan
- Department of Biomedical Sciences University of Windsor Windsor Ontario Canada
| | - Michael J. Crawford
- Department of Biomedical Sciences University of Windsor Windsor Ontario Canada
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Transcriptional analysis of scar-free wound healing during early stages of tail regeneration in the green anole lizard, Anolis carolinensis. ACTA ACUST UNITED AC 2020. [DOI: 10.1016/j.regen.2019.100025] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Tsai SL, Baselga-Garriga C, Melton DA. Midkine is a dual regulator of wound epidermis development and inflammation during the initiation of limb regeneration. eLife 2020; 9:50765. [PMID: 31934849 PMCID: PMC6959999 DOI: 10.7554/elife.50765] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 12/23/2019] [Indexed: 12/13/2022] Open
Abstract
Formation of a specialized wound epidermis is required to initiate salamander limb regeneration. Yet little is known about the roles of the early wound epidermis during the initiation of regeneration and the mechanisms governing its development into the apical epithelial cap (AEC), a signaling structure necessary for outgrowth and patterning of the regenerate. Here, we elucidate the functions of the early wound epidermis, and further reveal midkine (mk) as a dual regulator of both AEC development and inflammation during the initiation of axolotl limb regeneration. Through loss- and gain-of-function experiments, we demonstrate that mk acts as both a critical survival signal to control the expansion and function of the early wound epidermis and an anti-inflammatory cytokine to resolve early injury-induced inflammation. Altogether, these findings unveil one of the first identified regulators of AEC development and provide fundamental insights into early wound epidermis function, development, and the initiation of limb regeneration.
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Affiliation(s)
- Stephanie L Tsai
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, United States.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Clara Baselga-Garriga
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, United States.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, United States
| | - Douglas A Melton
- Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, United States
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21
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Alibardi L. Immunolocalization of Wnts in the lizard blastema supports a key role of these signaling proteins for tail regeneration. J Morphol 2019; 281:68-80. [PMID: 31721289 DOI: 10.1002/jmor.21080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/30/2019] [Accepted: 10/25/2019] [Indexed: 12/13/2022]
Abstract
A highly upregulated gene during tail regeneration in lizards is Wnt2b, a gene broadly expressed during development. The present study examines the distribution of Wnt proteins, most likely wnt2b, by western blotting and immunofluorescence in the blastema-cone of lizards using a specific antibody produced against a lizard Wnt2b protein. Immunopositive bands at 48-50 and 18 kDa are present in the regenerative blastema, the latter likely as a degradation product. Immunofluorescence is mainly observed in the wound epidermis, including in the Apical Epidermal Peg where the protein appears localized in intermediate and differentiating keratinocytes. Labeling is more intense along the perimeter of keratinocytes, possibly as a secretory product, and indicates that the high epidermal proliferation of the regenerating epidermis is sustained by Wnt proteins. The regenerating spinal cord forms an ependymal tube within the blastema and shows immunolabeling especially in the cytoplasm of ependymal cells contacting the central canal where some secretion might occur. Also, regenerating nerves and proximal spinal ganglia innervating the regenerating blastema contain this signaling protein. In contrast, the blastema mesenchyme, muscles and cartilage show weak immunolabeling that tends to disappear in tissues located in more proximal regions, close to the original tail. However, a distal to proximal gradient of Wnt proteins was not detected. The present study supports the hypothesis that Wnt proteins, in particular Wnt2b, are secreted by the apical epidermis covering the blastema and released into the mesenchyme where they stimulate cell multiplication.
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Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab Padova and Department of Biology, University of Bologna, Bologna, Italy
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22
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Zhang Q, Fan H, Liu H, Jin J, Zhu S, Zhou L, Liu H, Zhang F, Zhan P, Lv T, Song Y. WNT5B exerts oncogenic effects and is negatively regulated by miR-5587-3p in lung adenocarcinoma progression. Oncogene 2019; 39:1484-1497. [PMID: 31666682 DOI: 10.1038/s41388-019-1071-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 10/05/2019] [Accepted: 10/11/2019] [Indexed: 12/29/2022]
Abstract
WNT5B glycoprotein belongs to the Wnt protein family. Limited investigations revealed a possible role of WNT5B in malignancies, such as triple-negative breast cancer and oral squamous cell carcinoma. However, whether WNT5B contributes to the progression of lung adenocarcinoma (LAD) remains unclear. Here, we initially determine that WNT5B is highly expressed in LAD and is positively correlated with lymph node metastasis and TNM stage. Consistently, clinical analysis reveals WNT5B as an independent prognostic biomarker in LAD. Silencing WNT5B suppresses the proliferation of LAD both in vitro and in vivo by interfering G1/S cell-cycle progression and modulating amino acid metabolism, revealing its remarkable oncogenic role in LAD. Of note, we also identified miR-5587-3p as a negative upstream regulator of WNT5B in LAD, which may help develop therapies targeting LAD patients with high WNT5B expression. Taken together, our results revealed an oncogenic role of WNT5B in LAD, which could be a prognostic biomarker and promising therapeutic target for LAD patients.
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Affiliation(s)
- Qun Zhang
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China.,Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Hang Fan
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China
| | - Hongda Liu
- Department of General Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
| | - Jiajia Jin
- Department of Respiratory Medicine, Jinling Hospital, Southern Medical University, Nanjing, 210002, Jiangsu, China
| | - Suhua Zhu
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China
| | - Li Zhou
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China
| | - Hongbin Liu
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China
| | - Fang Zhang
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China
| | - Ping Zhan
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China.
| | - Tangfeng Lv
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China.
| | - Yong Song
- Department of Respiratory Medicine, Jinling Hospital, Nanjing University School of Medicine, Nanjing, 210002, Jiangsu, China.
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23
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Bichirs employ similar genetic pathways for limb regeneration as are used in lungfish and salamanders. Gene 2019; 690:68-74. [DOI: 10.1016/j.gene.2018.12.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 10/29/2018] [Accepted: 12/12/2018] [Indexed: 11/22/2022]
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24
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Alibardi L. Hyaluronic acid in the tail and limb of amphibians and lizards recreates permissive embryonic conditions for regeneration due to its hygroscopic and immunosuppressive properties. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2017; 328:760-771. [DOI: 10.1002/jez.b.22771] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/19/2017] [Accepted: 08/29/2017] [Indexed: 01/03/2023]
Affiliation(s)
- Lorenzo Alibardi
- Comparative Histolab; Padova Italy
- Department of Biology; University of Bologna; Bologna Italy
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25
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Stocum DL. Mechanisms of urodele limb regeneration. REGENERATION (OXFORD, ENGLAND) 2017; 4:159-200. [PMID: 29299322 PMCID: PMC5743758 DOI: 10.1002/reg2.92] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Accepted: 10/04/2017] [Indexed: 12/21/2022]
Abstract
This review explores the historical and current state of our knowledge about urodele limb regeneration. Topics discussed are (1) blastema formation by the proteolytic histolysis of limb tissues to release resident stem cells and mononucleate cells that undergo dedifferentiation, cell cycle entry and accumulation under the apical epidermal cap. (2) The origin, phenotypic memory, and positional memory of blastema cells. (3) The role played by macrophages in the early events of regeneration. (4) The role of neural and AEC factors and interaction between blastema cells in mitosis and distalization. (5) Models of pattern formation based on the results of axial reversal experiments, experiments on the regeneration of half and double half limbs, and experiments using retinoic acid to alter positional identity of blastema cells. (6) Possible mechanisms of distalization during normal and intercalary regeneration. (7) Is pattern formation is a self-organizing property of the blastema or dictated by chemical signals from adjacent tissues? (8) What is the future for regenerating a human limb?
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Affiliation(s)
- David L. Stocum
- Department of BiologyIndiana University−Purdue University Indianapolis723 W. Michigan StIndianapolisIN 46202USA
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26
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Abstract
Humans and other mammals are limited in their natural abilities to regenerate lost body parts. By contrast, many salamanders are highly regenerative and can spontaneously replace lost limbs even as adults. Because salamander limbs are anatomically similar to human limbs, knowing how they regenerate should provide important clues for regenerative medicine. Although interest in understanding the mechanics of this process has never wavered, until recently researchers have been vexed by seemingly impenetrable logistics of working with these creatures at a molecular level. Chief among the problems has been the very large size of salamander genomes, and not a single salamander genome has been fully sequenced to date. Recently the enormous gap in sequence information has been bridged by approaches that leverage mRNA as the starting point. Together with functional experimentation, these data are rapidly enabling researchers to finally uncover the molecular mechanisms underpinning the astonishing biological process of limb regeneration.
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Affiliation(s)
- Brian J Haas
- Broad Institute of Massachusetts Institute of Technology(MIT) and Harvard, Klarman Cell Observatory, 415 Main Street, Cambridge, MA 02142, USA.
| | - Jessica L Whited
- Harvard Medical School, Harvard Stem Cell Institute, and Brigham and Women's Hospital Department of Orthopedic Surgery, 60 Fenwood Road, Boston, MA 02115, USA.
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27
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Vitulo N, Dalla Valle L, Skobo T, Valle G, Alibardi L. Transcriptome analysis of the regenerating tail vs. the scarring limb in lizard reveals pathways leading to successful vs. unsuccessful organ regeneration in amniotes. Dev Dyn 2017; 246:116-134. [DOI: 10.1002/dvdy.24474] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 11/12/2016] [Accepted: 11/16/2016] [Indexed: 12/29/2022] Open
Affiliation(s)
- Nicola Vitulo
- Department of Biotechnology; University of Verona; Italy
| | | | - Tatjana Skobo
- Department of Biology; University of Padova; Padova Italy
| | - Giorgio Valle
- Department of Biology; University of Padova; Padova Italy
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28
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Abstract
Tissue growth and regeneration are autonomous, stem-cell-mediated processes in which stem cells within the organ self-renew and differentiate to create new cells, leading to new tissue. The processes of growth and regeneration require communication and interplay between neighboring cells. In particular, cell competition, which is a process in which viable cells are actively eliminated by more competitive cells, has been increasingly implicated to play an important role. Here, we discuss the existing literature regarding the current landscape of cell competition, including classical pathways and models, fitness fingerprint mechanisms, and immune system mechanisms of cell competition. We further discuss the clinical relevance of cell competition in the physiological processes of tissue growth and regeneration, highlighting studies in clinically important disease models, including oncological, neurological, and cardiovascular diseases.
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Affiliation(s)
- Rajan Gogna
- Institut für Zellbiologie, University of Bern, CH-3012 Bern, Switzerland; .,Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire 03766
| | - Kevin Shee
- Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth College, Hanover, New Hampshire 03766
| | - Eduardo Moreno
- Institut für Zellbiologie, University of Bern, CH-3012 Bern, Switzerland;
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29
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Regeneration: Lessons from the Lizard. INNOVATIONS IN MOLECULAR MECHANISMS AND TISSUE ENGINEERING 2016. [DOI: 10.1007/978-3-319-44996-8_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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30
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Rodrigo Albors A, Tazaki A, Rost F, Nowoshilow S, Chara O, Tanaka EM. Planar cell polarity-mediated induction of neural stem cell expansion during axolotl spinal cord regeneration. eLife 2015; 4:e10230. [PMID: 26568310 PMCID: PMC4755742 DOI: 10.7554/elife.10230] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 11/12/2015] [Indexed: 02/07/2023] Open
Abstract
Axolotls are uniquely able to mobilize neural stem cells to regenerate all missing regions of the spinal cord. How a neural stem cell under homeostasis converts after injury to a highly regenerative cell remains unknown. Here, we show that during regeneration, axolotl neural stem cells repress neurogenic genes and reactivate a transcriptional program similar to embryonic neuroepithelial cells. This dedifferentiation includes the acquisition of rapid cell cycles, the switch from neurogenic to proliferative divisions, and the re-expression of planar cell polarity (PCP) pathway components. We show that PCP induction is essential to reorient mitotic spindles along the anterior-posterior axis of elongation, and orthogonal to the cell apical-basal axis. Disruption of this property results in premature neurogenesis and halts regeneration. Our findings reveal a key role for PCP in coordinating the morphogenesis of spinal cord outgrowth with the switch from a homeostatic to a regenerative stem cell that restores missing tissue. DOI:http://dx.doi.org/10.7554/eLife.10230.001 Stem cells found in adult tissues are vitally important for tissue repair and maintenance. These cells divide in two main ways: equally to create two new stem cells, or unequally to create a stem cell and a cell that can develop into one of the cell types in the tissue. A key challenge for biologists is to understand how these tissue-resident stem cells are activated and organized to regenerate injured or missing tissue. Throughout the life of the axolotl salamander, neural stem cells in the spinal cord occasionally divide to add new nerve cells to the healthy spinal cord. However, the axolotl can also regenerate part of its spinal cord, for example if its tail is lost. Under these conditions, the neural stem cells can convert into a highly regenerative stem cell that can produce all the different cell types needed to regrow the spinal cord. As a stem cell becomes a new cell type, it activates different sets of genes. Therefore, Rodrigo Albors, Tazaki et al. measured gene activity in the neural stem cells involved in axolotl spinal cord regeneration to uncover how these cells develop into a more regenerative form. This revealed that when an axolotl tail is amputated, resident stem cells turn off the genes that are specifically active in neuron-generating cells. In addition, they activate a similar set of genes to that seen in the embryonic cells that form the developing nervous system. These genes speed up cell division and activate an important signaling pathway. This pathway – the Wnt/PCP pathway – fulfils various developmental roles, one being to orient cell divisions, particularly in elongating tissues. In axolotls, this pathway causes the stem cells to divide equally to increase the number of available stem cells, and orients the direction of these divisions to ensure that the regenerating spinal cord elongates correctly. If this pathway is disrupted, the cells return to dividing unequally, generating nerve cells prematurely and halting the growth of the spinal cord. Such insights could help develop methods of repairing damaged nervous tissue in other animals that cannot regenerate to the extent that axolotls can. DOI:http://dx.doi.org/10.7554/eLife.10230.002
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Affiliation(s)
- Aida Rodrigo Albors
- Deutsche Forschungsgemeinschaft - Center for Regenerative Therapies Dresden, Dresden, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Technische Universität Dresden, Dresden, Germany
| | - Akira Tazaki
- Deutsche Forschungsgemeinschaft - Center for Regenerative Therapies Dresden, Dresden, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Technische Universität Dresden, Dresden, Germany
| | - Fabian Rost
- Center for Information Services and High Performance Computing, Technische Universität Dresden, Dresden, Germany
| | - Sergej Nowoshilow
- Deutsche Forschungsgemeinschaft - Center for Regenerative Therapies Dresden, Dresden, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Technische Universität Dresden, Dresden, Germany
| | - Osvaldo Chara
- Center for Information Services and High Performance Computing, Technische Universität Dresden, Dresden, Germany.,Institute of Physics of Liquids and Biological Systems, National Scientific and Technical Research Council, University of La Plata, La Plata, Argentina
| | - Elly M Tanaka
- Deutsche Forschungsgemeinschaft - Center for Regenerative Therapies Dresden, Dresden, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Technische Universität Dresden, Dresden, Germany
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31
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Wang X, Hsi TC, Guerrero-Juarez CF, Pham K, Cho K, McCusker CD, Monuki ES, Cho KWY, Gay DL, Plikus MV. Principles and mechanisms of regeneration in the mouse model for wound-induced hair follicle neogenesis. ACTA ACUST UNITED AC 2015; 2:169-181. [PMID: 26504521 PMCID: PMC4617665 DOI: 10.1002/reg2.38] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Wound‐induced hair follicle neogenesis (WIHN) describes a regenerative phenomenon in adult mammalian skin wherein fully functional hair follicles regenerate de novo in the center of large excisional wounds. Originally described in rats, rabbits, sheep, and humans in 1940−1960, the WIHN phenomenon was reinvestigated in mice only recently. The process of de novo hair regeneration largely duplicates the morphological and signaling features of normal embryonic hair development. Similar to hair development, WIHN critically depends on the activation of canonical WNT signaling. However, unlike hair development, WNT activation in WIHN is dependent on fibroblast growth factor 9 signaling generated by the immune system's γδ T cells. The cellular bases of WIHN remain to be fully characterized; however, the available evidence leaves open the possibility for a blastema‐like mechanism wherein epidermal and/or dermal wound cells undergo epigenetic reprogramming toward a more plastic, embryonic‐like state. De novo hair follicles do not regenerate from preexisting hair‐fated bulge stem cells. This suggests that hair neogenesis is not driven by preexisting lineage‐restricted progenitors, as is the case for amputation‐induced mouse digit tip regeneration, but rather may require a blastema‐like mechanism. The WIHN model is characterized by several intriguing features, which await further explanation. These include (1) the minimum wound size requirement for activating neogenesis, (2) the restriction of hair neogenesis to the wound's center, and (3) imperfect patterning outcomes, both in terms of neogenic hair positioning within the wound and in terms of their orientation. Future enquiries into the WIHN process, made possible by a wide array of available skin‐specific genetic tools, will undoubtedly expand our understanding of the regeneration mechanisms in adult mammals.
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Affiliation(s)
- Xiaojie Wang
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Tsai-Ching Hsi
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Christian Fernando Guerrero-Juarez
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Kim Pham
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Kevin Cho
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Catherine D McCusker
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Edwin S Monuki
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA ; Department of Pathology and Laboratory Medicine, University of California, Irvine, Irvine, CA 92697, USA
| | - Ken W Y Cho
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Denise L Gay
- UMR 967, Cellules Souches et Radiations, CEA - INSERM - Universités Paris 7 et Paris 11, CEA/DSV/IRCM/SCSR/LRTS, 92265 Fontenay-aux-Roses Cedex, France
| | - Maksim V Plikus
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA ; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA ; Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
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Protein expression profiling in head fragments during planarian regeneration after amputation. Dev Genes Evol 2015; 225:79-93. [PMID: 25697422 DOI: 10.1007/s00427-015-0494-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 02/09/2015] [Indexed: 10/24/2022]
Abstract
Following amputation, a planarian tail fragment can regrow into a complete organism including a well-organized brain within about 2-3 weeks, thus restoring the structure and function to presurgical levels. Despite the enormous potential of these animals for regenerative medicine, our understanding of the exact mechanism of planarian regeneration is incomplete. To better understand the molecular nature of planarian head regeneration, we applied two-dimensional electrophoresis (2-DE)/matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF)/time-of-flight mass spectrometry (TOF MS) technique to analyze the dynamic proteomic expression profiles over the course of 6 to 168 h post-decapitation. This approach identified a total of 141 differentially expressed proteins, 47 of which exhibited exceptionally high fold changes (≥3-fold change). Of these, Rx protein, an important regulator of head and brain development, was considered to be closely related to planarian head regeneration because of its exceptional high expression almost throughout the time course of regeneration process. Functional annotation analysis classified the 141 proteins into eight categories: (1) signaling, (2) Ca(2+) binding and translocation, (3) transcription and translation, (4) cytoskeleton, (5) metabolism, (6) cell protection, (7) tissue differentiation, and (8) cell cycle. Signaling pathway analysis indicated that Wnt1/Ca(2+) signaling pathway was activated during head regeneration. Integrating the analyses of proteome expression profiling, functional annotation, and signaling pathway, amputation-induced head reformation requires some mechanisms to promote cell proliferation and differentiation, including differential regulation of proapoptotic and antiapoptotic proteins, and the regulation of proliferation and differentiation-related proteins. Importantly, Wnt1/Ca(2+) signaling pathway upregulates Rx expression, finally facilitating the differentiation of neoblasts into various cell types. Taken together, our study demonstrated that proteomic analysis approach used by us is a powerful tool in understanding molecular process related to head regeneration of planarian.
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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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McCusker CD, Gardiner DM. Understanding positional cues in salamander limb regeneration: implications for optimizing cell-based regenerative therapies. Dis Model Mech 2014; 7:593-9. [PMID: 24872456 PMCID: PMC4036467 DOI: 10.1242/dmm.013359] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Regenerative medicine has reached the point where we are performing clinical trials with stem-cell-derived cell populations in an effort to treat numerous human pathologies. However, many of these efforts have been challenged by the inability of the engrafted populations to properly integrate into the host environment to make a functional biological unit. It is apparent that we must understand the basic biology of tissue integration in order to apply these principles to the development of regenerative therapies in humans. Studying tissue integration in model organisms, where the process of integration between the newly regenerated tissues and the ‘old’ existing structures can be observed and manipulated, can provide valuable insights. Embryonic and adult cells have a memory of their original position, and this positional information can modify surrounding tissues and drive the formation of new structures. In this Review, we discuss the positional interactions that control the ability of grafted cells to integrate into existing tissues during the process of salamander limb regeneration, and discuss how these insights could explain the integration defects observed in current cell-based regenerative therapies. Additionally, we describe potential molecular tools that can be used to manipulate the positional information in grafted cell populations, and to promote the communication of positional cues in the host environment to facilitate the integration of engrafted cells. Lastly, we explain how studying positional information in current cell-based therapies and in regenerating limbs could provide key insights to improve the integration of cell-based regenerative therapies in the future.
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Affiliation(s)
- Catherine D McCusker
- Francisco J. Ayala School of Biological Sciences, Department of Developmental and Cell Biology, University of California Irvine, CA 92602, USA.
| | - David M Gardiner
- Francisco J. Ayala School of Biological Sciences, Department of Developmental and Cell Biology, University of California Irvine, CA 92602, USA
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Hui SP, Sengupta D, Lee SGP, Sen T, Kundu S, Mathavan S, Ghosh S. Genome wide expression profiling during spinal cord regeneration identifies comprehensive cellular responses in zebrafish. PLoS One 2014; 9:e84212. [PMID: 24465396 PMCID: PMC3896338 DOI: 10.1371/journal.pone.0084212] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 11/21/2013] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Among the vertebrates, teleost and urodele amphibians are capable of regenerating their central nervous system. We have used zebrafish as a model to study spinal cord injury and regeneration. Relatively little is known about the molecular mechanisms underlying spinal cord regeneration and information based on high density oligonucleotide microarray was not available. We have used a high density microarray to profile the temporal transcriptome dynamics during the entire phenomenon. RESULTS A total of 3842 genes expressed differentially with significant fold changes during spinal cord regeneration. Cluster analysis revealed event specific dynamic expression of genes related to inflammation, cell death, cell migration, cell proliferation, neurogenesis, neural patterning and axonal regrowth. Spatio-temporal analysis of stat3 expression suggested its possible function in controlling inflammation and cell proliferation. Genes involved in neurogenesis and their dorso-ventral patterning (sox2 and dbx2) are differentially expressed. Injury induced cell proliferation is controlled by many cell cycle regulators and some are commonly expressed in regenerating fin, heart and retina. Expression pattern of certain pathway genes are identified for the first time during regeneration of spinal cord. Several genes involved in PNS regeneration in mammals like stat3, socs3, atf3, mmp9 and sox11 are upregulated in zebrafish SCI thus creating PNS like environment after injury. CONCLUSION Our study provides a comprehensive genetic blue print of diverse cellular response(s) during regeneration of zebrafish spinal cord. The data highlights the importance of different event specific gene expression that could be better understood and manipulated further to induce successful regeneration in mammals.
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Affiliation(s)
- Subhra Prakash Hui
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
| | - Dhriti Sengupta
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
| | | | - Triparna Sen
- Chittaranjan National Cancer Research Institute, Kolkata, India
| | - Sudip Kundu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
| | | | - Sukla Ghosh
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
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Knapp D, Schulz H, Rascon CA, Volkmer M, Scholz J, Nacu E, Le M, Novozhilov S, Tazaki A, Protze S, Jacob T, Hubner N, Habermann B, Tanaka EM. Comparative transcriptional profiling of the axolotl limb identifies a tripartite regeneration-specific gene program. PLoS One 2013; 8:e61352. [PMID: 23658691 PMCID: PMC3641036 DOI: 10.1371/journal.pone.0061352] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 03/12/2013] [Indexed: 01/08/2023] Open
Abstract
Understanding how the limb blastema is established after the initial wound healing response is an important aspect of regeneration research. Here we performed parallel expression profile time courses of healing lateral wounds versus amputated limbs in axolotl. This comparison between wound healing and regeneration allowed us to identify amputation-specific genes. By clustering the expression profiles of these samples, we could detect three distinguishable phases of gene expression - early wound healing followed by a transition-phase leading to establishment of the limb development program, which correspond to the three phases of limb regeneration that had been defined by morphological criteria. By focusing on the transition-phase, we identified 93 strictly amputation-associated genes many of which are implicated in oxidative-stress response, chromatin modification, epithelial development or limb development. We further classified the genes based on whether they were or were not significantly expressed in the developing limb bud. The specific localization of 53 selected candidates within the blastema was investigated by in situ hybridization. In summary, we identified a set of genes that are expressed specifically during regeneration and are therefore, likely candidates for the regulation of blastema formation.
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Affiliation(s)
- Dunja Knapp
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Herbert Schulz
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Cynthia Alexander Rascon
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Michael Volkmer
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Max Planck Institute for Biology of Aging, Cologne, Germany
| | - Juliane Scholz
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Eugen Nacu
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Mu Le
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Sergey Novozhilov
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Akira Tazaki
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
| | - Stephanie Protze
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Tina Jacob
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Norbert Hubner
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany
| | - Bianca Habermann
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Max Planck Institute for Biology of Aging, Cologne, Germany
| | - Elly M. Tanaka
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Technical University Dresden, DFG Research Center for Regenerative Therapies Dresden, Dresden, Germany
- * E-mail:
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Giangrande A, Licciano M. Regeneration and clonality in Metazoa. The price to pay for evolving complexity. INVERTEBR REPROD DEV 2013. [DOI: 10.1080/07924259.2013.793622] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Murawala P, Tanaka EM, Currie JD. Regeneration: the ultimate example of wound healing. Semin Cell Dev Biol 2012; 23:954-62. [PMID: 23059793 DOI: 10.1016/j.semcdb.2012.09.013] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 09/27/2012] [Indexed: 01/13/2023]
Abstract
The outcome of wound repair in mammals is often characterized by fibrotic scaring. Vertebrates such as zebrafish, frogs, and salamanders not only heal scarlessly, but also can regenerate lost appendages. Decades of study on the process of animal regeneration has produced key insights into the mechanisms of how complex tissue is restored. By examining our current knowledge of regeneration, we can draw parallels with mammalian wound healing to identify the molecular determinants that produce such differing outcomes.
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Affiliation(s)
- Prayag Murawala
- Technische Universität Dresden, DFG Center for Regenerative Therapies, Fetscherstrasse 105, Dresden 01307, Germany
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Monaghan JR, Athippozhy A, Seifert AW, Putta S, Stromberg AJ, Maden M, Gardiner DM, Voss SR. Gene expression patterns specific to the regenerating limb of the Mexican axolotl. Biol Open 2012; 1:937-48. [PMID: 23213371 PMCID: PMC3507169 DOI: 10.1242/bio.20121594] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 06/14/2012] [Indexed: 01/05/2023] Open
Abstract
Salamander limb regeneration is dependent upon tissue interactions that are local to the amputation site. Communication among limb epidermis, peripheral nerves, and mesenchyme coordinate cell migration, cell proliferation, and tissue patterning to generate a blastema, which will form missing limb structures. An outstanding question is how cross-talk between these tissues gives rise to the regeneration blastema. To identify genes associated with epidermis-nerve-mesenchymal interactions during limb regeneration, we examined histological and transcriptional changes during the first week following injury in the wound epidermis and subjacent cells between three injury types; 1) a flank wound on the side of the animal that will not regenerate a limb, 2) a denervated limb that will not regenerate a limb, and 3) an innervated limb that will regenerate a limb. Early, histological and transcriptional changes were similar between the injury types, presumably because a common wound-healing program is employed across anatomical locations. However, some transcripts were enriched in limbs compared to the flank and are associated with vertebrate limb development. Many of these genes were activated before blastema outgrowth and expressed in specific tissue types including the epidermis, peripheral nerve, and mesenchyme. We also identified a relatively small group of transcripts that were more highly expressed in innervated limbs versus denervated limbs. These transcripts encode for proteins involved in myelination of peripheral nerves, epidermal cell function, and proliferation of mesenchymal cells. Overall, our study identifies limb-specific and nerve-dependent genes that are upstream of regenerative growth, and thus promising candidates for the regulation of blastema formation.
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Affiliation(s)
- James R Monaghan
- Department of Biology, University of Florida , Gainesville, FL 32611 , USA
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Visualization of retinoic acid signaling in transgenic axolotls during limb development and regeneration. Dev Biol 2012; 368:63-75. [PMID: 22627291 DOI: 10.1016/j.ydbio.2012.05.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 04/26/2012] [Accepted: 05/10/2012] [Indexed: 12/16/2022]
Abstract
Retinoic acid (RA) plays a necessary role in limb development and regeneration, but the precise mechanism by which it acts during these processes is unclear. The role of RA in limb regeneration was first highlighted by the remarkable effect that it has on respecifying the proximodistal axis of the regenerating limb so that serially repeated limbs are produced. To facilitate the study of RA signaling during development and then during regeneration of the same structure we have turned to the axolotl, the master of vertebrate regeneration, and generated transgenic animals that fluorescently report RA signaling in vivo. Characterization of these animals identified an anterior segment of the developing embryo where RA signaling occurs revealing conserved features of the early vertebrate embryo. During limb development RA signaling was present in the developing forelimb bud mesenchyme, but was not detected during hindlimb development. During limb regeneration, RA signaling was surprisingly almost exclusively observed in the apical epithelium suggesting a different role of RA during limb regeneration. After the addition of supplemental RA to regenerating limbs that leads to pattern duplications, the fibroblast stem cells of the blastema responded showing that they are capable of transcriptionally responding to RA. These findings are significant because it means that RA signaling may play a multifunctional role during forelimb development and regeneration and that the fibroblast stem cells that regulate proximodistal limb patterning during regeneration are targets of RA signaling.
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Abstract
Salamander limb regeneration is a classical model of tissue morphogenesis and patterning. Through recent advances in cell labeling and molecular analysis, a more precise, mechanistic understanding of this process has started to emerge. Long-standing questions include to what extent limb regeneration recapitulates the events observed in mammalian limb development and to what extent are adult- or salamander- specific aspects deployed. Historically, researchers studying limb development and limb regeneration have proposed different models of pattern formation. Here we discuss recent data on limb regeneration and limb development to argue that although patterning mechanisms are likely to be similar, cell plasticity and signaling from nerves play regeneration-specific roles.
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Affiliation(s)
- Eugen Nacu
- DFG-Center for Regenerative Therapies Dresden, Germany.
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Campbell LJ, Suárez-Castillo EC, Ortiz-Zuazaga H, Knapp D, Tanaka EM, Crews CM. Gene expression profile of the regeneration epithelium during axolotl limb regeneration. Dev Dyn 2011; 240:1826-40. [PMID: 21648017 PMCID: PMC3297817 DOI: 10.1002/dvdy.22669] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2011] [Indexed: 12/11/2022] Open
Abstract
Urodele amphibians are unique among adult vertebrates in their ability to regenerate missing limbs. The process of limb regeneration requires several key tissues including a regeneration-competent wound epidermis called the regeneration epithelium (RE). We used microarray analysis to profile gene expression of the RE in the axolotl, a Mexican salamander. A list of 125 genes and expressed sequence tags (ESTs) showed a ≥1.5-fold expression in the RE than in a wound epidermis covering a lateral cuff wound. A subset of the RE ESTs and genes were further characterized for expression level changes over the time-course of regeneration. This study provides the first large scale identification of specific gene expression in the RE.
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Affiliation(s)
- Leah J. Campbell
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Edna C. Suárez-Castillo
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Humberto Ortiz-Zuazaga
- High Performance Computing facility, Río Piedras Campus, University of Puerto Rico, San Juan, PR, USA
- Department of Computer Science, Río Piedras Campus, University of Puerto Rico, San Juan, PR, USA
| | - Dunja Knapp
- Center for Regenerative Therapies, Dresden, Germany
| | | | - Craig M. Crews
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Department of Chemistry, Yale University, New Haven, CT, USA
- Department of Pharmacology, Yale University, New Haven, CT, USA
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Zattara EE, Bely AE. Evolution of a novel developmental trajectory: fission is distinct from regeneration in the annelid Pristina leidyi. Evol Dev 2011; 13:80-95. [PMID: 21210945 DOI: 10.1111/j.1525-142x.2010.00458.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Understanding how novelty arises has been a major focus of evolutionary developmental biology. While the origin of new genes, gene functions, and morphological features has been studied intensely, the origin of entire developmental trajectories, such as regeneration or agametic reproduction, remains poorly understood. Agametic reproduction by fission is a novel trajectory evolved numerous times among animal phyla, including Annelida, in which it is thought to arise by co-option of regeneration. To gain insight into how a novel trajectory may evolve, we investigated a relatively recent origin of fission. We performed a detailed comparison of morphogenesis during regeneration and fission in the annelid Pristina leidyi (Clitellata, Naididae), from the onset of these trajectories to the achievement of the final morphology. We find extensive similarities between fission and regeneration morphogenesis, and, of particular note, find evidence for a synapomorphy of fission and regeneration (apparently not shared with embryogenesis) in peripheral nervous system development, providing strong support for the hypothesis that fission is derived from regeneration. We also find important differences between fission and regeneration, during development of multiple organ systems. These are manifested by temporal shifts in developmental events and by the presence of elements unique to only one process. Differences are not obviously temporally clustered at the beginning, middle, or end of development but rather occur throughout, indicating that divergence has occurred along the entire developmental course of these trajectories.
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Affiliation(s)
- Eduardo E Zattara
- Biology Department, University of Maryland, College Park, MD 20742, USA
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Abstract
The various Wnt pathways that are related to upper limb anomalies are reviewed. Abnormalities in the Wnt7a pathway (located in the dorsal ectoderm) produce several clinically relevant conditions such as the palmar duplication syndrome, nail patella syndrome, ulnar ray deficiency, limb hypoplasia, polysyndactyly and the palmar nail syndrome. Abnormalities of the Wnt3/3a pathway (located in the apical ectodermal ridge) include tetra-amelia and loss of the distal phalanges/nails. Abnormalities of the Wnt5/5a pathway (located in the apical ectodermal ridge as well as in the mesoderm) will affect chondrogenesis of the developing limb and experimental Wnt5a(-/-) limbs have terminal adactyly. Chondrogenesis and limb muscle differentiation are both affected by several Wnt pathways and these will be reviewed in details. Abnormalities in LRP 5/6 (a co-receptor for Wnts) lead to congenital bone disease and Wnt4 is specifically involved in joint development. Finally, the relationship between the Wnt pathway and SALL4 (mutations of which cause Okihiro/Duane-radial ray deficiency in humans) are discussed.
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Antos CL, Tanaka EM. Vertebrates that regenerate as models for guiding stem cels. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 695:184-214. [PMID: 21222207 DOI: 10.1007/978-1-4419-7037-4_13] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
There are several animal model organisms that have the ability to regenerate severe injuries by stimulating local cells to restore damaged and lost organs and appendages. In this chapter, we will describe how various vertebrate animals regenerate different structures (central nervous system, heart and appendages) as well as detail specific cellular and molecular features concerning the regeneration of these structures.
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Affiliation(s)
- Christopher L Antos
- DFG-Center for Regenerative Therapies Dresden, Technische Universität Dresden, Tatzberg 47/49, 01307, Dresden, Germany,
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Rao N, Jhamb D, Milner DJ, Li B, Song F, Wang M, Voss SR, Palakal M, King MW, Saranjami B, Nye HLD, Cameron JA, Stocum DL. Proteomic analysis of blastema formation in regenerating axolotl limbs. BMC Biol 2009; 7:83. [PMID: 19948009 PMCID: PMC2794268 DOI: 10.1186/1741-7007-7-83] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Accepted: 11/30/2009] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Following amputation, urodele salamander limbs reprogram somatic cells to form a blastema that self-organizes into the missing limb parts to restore the structure and function of the limb. To help understand the molecular basis of blastema formation, we used quantitative label-free liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS)-based methods to analyze changes in the proteome that occurred 1, 4 and 7 days post amputation (dpa) through the mid-tibia/fibula of axolotl hind limbs. RESULTS We identified 309 unique proteins with significant fold change relative to controls (0 dpa), representing 10 biological process categories: (1) signaling, (2) Ca2+ binding and translocation, (3) transcription, (4) translation, (5) cytoskeleton, (6) extracellular matrix (ECM), (7) metabolism, (8) cell protection, (9) degradation, and (10) cell cycle. In all, 43 proteins exhibited exceptionally high fold changes. Of these, the ecotropic viral integrative factor 5 (EVI5), a cell cycle-related oncoprotein that prevents cells from entering the mitotic phase of the cell cycle prematurely, was of special interest because its fold change was exceptionally high throughout blastema formation. CONCLUSION Our data were consistent with previous studies indicating the importance of inositol triphosphate and Ca2+ signaling in initiating the ECM and cytoskeletal remodeling characteristic of histolysis and cell dedifferentiation. In addition, the data suggested that blastema formation requires several mechanisms to avoid apoptosis, including reduced metabolism, differential regulation of proapoptotic and antiapoptotic proteins, and initiation of an unfolded protein response (UPR). Since there is virtually no mitosis during blastema formation, we propose that high levels of EVI5 function to arrest dedifferentiated cells somewhere in the G1/S/G2 phases of the cell cycle until they have accumulated under the wound epidermis and enter mitosis in response to neural and epidermal factors. Our findings indicate the general value of quantitative proteomic analysis in understanding the regeneration of complex structures.
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Affiliation(s)
- Nandini Rao
- Department of Biology and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Deepali Jhamb
- School of Informatics and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Derek J Milner
- Department of Cell and Developmental Biology, and Regeneration Biology and Tissue Engineering Theme, Institute for Genomic Biology, University of Illinois-Urbana Champaign, Urbana, IL, USA
| | - Bingbing Li
- Department of Biology and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Fengyu Song
- Department of Oral Biology, School of Dentistry and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Mu Wang
- Department of Biochemistry, School of Medicine and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - S Randal Voss
- Department of Biology and Spinal Cord and Brain Injury Center, University of Kentucky at Lexington, Lexington, KY, USA
| | - Mathew Palakal
- School of Informatics and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Michael W King
- Department of Biochemistry, School of Medicine and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Behnaz Saranjami
- Department of Biology and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
| | - Holly LD Nye
- Department of Cell and Developmental Biology, and Regeneration Biology and Tissue Engineering Theme, Institute for Genomic Biology, University of Illinois-Urbana Champaign, Urbana, IL, USA
| | - Jo Ann Cameron
- Department of Cell and Developmental Biology, and Regeneration Biology and Tissue Engineering Theme, Institute for Genomic Biology, University of Illinois-Urbana Champaign, Urbana, IL, USA
| | - David L Stocum
- Department of Biology and Center for Regenerative Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN, USA
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Monaghan JR, Epp LG, Putta S, Page RB, Walker JA, Beachy CK, Zhu W, Pao GM, Verma IM, Hunter T, Bryant SV, Gardiner DM, Harkins TT, Voss SR. Microarray and cDNA sequence analysis of transcription during nerve-dependent limb regeneration. BMC Biol 2009; 7:1. [PMID: 19144100 PMCID: PMC2630914 DOI: 10.1186/1741-7007-7-1] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 01/13/2009] [Indexed: 02/01/2023] Open
Abstract
Background Microarray analysis and 454 cDNA sequencing were used to investigate a centuries-old problem in regenerative biology: the basis of nerve-dependent limb regeneration in salamanders. Innervated (NR) and denervated (DL) forelimbs of Mexican axolotls were amputated and transcripts were sampled after 0, 5, and 14 days of regeneration. Results Considerable similarity was observed between NR and DL transcriptional programs at 5 and 14 days post amputation (dpa). Genes with extracellular functions that are critical to wound healing were upregulated while muscle-specific genes were downregulated. Thus, many processes that are regulated during early limb regeneration do not depend upon nerve-derived factors. The majority of the transcriptional differences between NR and DL limbs were correlated with blastema formation; cell numbers increased in NR limbs after 5 dpa and this yielded distinct transcriptional signatures of cell proliferation in NR limbs at 14 dpa. These transcriptional signatures were not observed in DL limbs. Instead, gene expression changes within DL limbs suggest more diverse and protracted wound-healing responses. 454 cDNA sequencing complemented the microarray analysis by providing deeper sampling of transcriptional programs and associated biological processes. Assembly of new 454 cDNA sequences with existing expressed sequence tag (EST) contigs from the Ambystoma EST database more than doubled (3935 to 9411) the number of non-redundant human-A. mexicanum orthologous sequences. Conclusion Many new candidate gene sequences were discovered for the first time and these will greatly enable future studies of wound healing, epigenetics, genome stability, and nerve-dependent blastema formation and outgrowth using the axolotl model.
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Affiliation(s)
- James R Monaghan
- Department of Biology and Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40506, USA.
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48
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Roy S, Gatien S. Regeneration in axolotls: a model to aim for! Exp Gerontol 2008; 43:968-73. [PMID: 18814845 DOI: 10.1016/j.exger.2008.09.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 08/18/2008] [Accepted: 09/02/2008] [Indexed: 10/21/2022]
Abstract
Urodele amphibians such as the axolotl are the champions of tissue regeneration amongst vertebrates. These animals have mastered the ability to repair and replace most of their tissues following damage or amputation even well into adulthood. In fact it seems that the ability of these organisms to regenerate perfectly is not affected by their age. In addition to being able to regenerate, these animals display a remarkable resistance to cancer. They therefore represent a unique model organism to study regeneration and cancer resistance in vertebrates. The need for this research is even more pressing at the dawn of the 21st century as we are faced with an ever aging world population which has to deal with an increase in organ failure and cancer incidence. Hopefully, this mini review will put in perspective some of the reasons why studying tissue regeneration in salamanders could yield significant knowledge to help regenerative medicine achieve the desired goal of allowing humans to repair and regenerate some of their own tissues as they age.
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Affiliation(s)
- Stéphane Roy
- Department of Stomatology, Faculty of Dentistry, Université de Montréal, Down-Town Branch, Montréal, QC, Canada.
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