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Grigoryan EN. Pigment Epithelia of the Eye: Cell-Type Conversion in Regeneration and Disease. Life (Basel) 2022; 12:life12030382. [PMID: 35330132 PMCID: PMC8955580 DOI: 10.3390/life12030382] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 02/28/2022] [Accepted: 03/03/2022] [Indexed: 12/17/2022] Open
Abstract
Pigment epithelial cells (PECs) of the retina (RPE), ciliary body, and iris (IPE) are capable of altering their phenotype. The main pathway of phenotypic switching of eye PECs in vertebrates and humans in vivo and/or in vitro is neural/retinal. Besides, cells of amphibian IPE give rise to the lens and its derivatives, while mammalian and human RPE can be converted along the mesenchymal pathway. The PECs’ capability of conversion in vivo underlies the lens and retinal regeneration in lower vertebrates and retinal diseases such as proliferative vitreoretinopathy and fibrosis in mammals and humans. The present review considers these processes studied in vitro and in vivo in animal models and in humans. The molecular basis of conversion strategies in PECs is elucidated. Being predetermined onto- and phylogenetically, it includes a species-specific molecular context, differential expression of transcription factors, signaling pathways, and epigenomic changes. The accumulated knowledge regarding the mechanisms of PECs phenotypic switching allows the development of approaches to specified conversion for many purposes: obtaining cells for transplantation, creating conditions to stimulate natural regeneration of the retina and the lens, blocking undesirable conversions associated with eye pathology, and finding molecular markers of pathology to be targets of therapy.
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Affiliation(s)
- Eleonora N Grigoryan
- Kol'tsov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia
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2
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Dolmatov IY. Molecular Aspects of Regeneration Mechanisms in Holothurians. Genes (Basel) 2021; 12:250. [PMID: 33578707 PMCID: PMC7916379 DOI: 10.3390/genes12020250] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Revised: 02/05/2021] [Accepted: 02/08/2021] [Indexed: 02/07/2023] Open
Abstract
Holothurians, or sea cucumbers, belong to the phylum Echinodermata. They show good regenerative abilities. The present review provides an analysis of available data on the molecular aspects of regeneration mechanisms in holothurians. The genes and signaling pathways activated during the asexual reproduction and the formation of the anterior and posterior parts of the body, as well as the molecular mechanisms that provide regeneration of the nervous and digestive systems, are considered here. Damage causes a strong stress response, the signs of which are recorded even at late regeneration stages. In holothurian tissues, the concentrations of reactive oxygen species and antioxidant enzymes increase. Furthermore, the cellular and humoral components of the immune system are activated. Extracellular matrix remodeling and Wnt signaling play a major role in the regeneration in holothurians. All available morphological and molecular data show that the dedifferentiation of specialized cells in the remnant of the organ and the epithelial morphogenesis constitute the basis of regeneration in holothurians. However, depending on the type of damage, the mechanisms of regeneration may differ significantly in the spatial organization of regeneration process, the involvement of different cell types, and the depth of reprogramming of their genome (dedifferentiation or transdifferentiation).
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Affiliation(s)
- Igor Yu Dolmatov
- A.V. Zhirmunsky National Scientifc Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Palchevsky 17, 690041 Vladivostok, Russia
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3
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Grigoryan EN. Study of Natural Longlife Juvenility and Tissue Regeneration in Caudate Amphibians and Potential Application of Resulting Data in Biomedicine. J Dev Biol 2021; 9:2. [PMID: 33477527 PMCID: PMC7838874 DOI: 10.3390/jdb9010002] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/07/2021] [Accepted: 01/12/2021] [Indexed: 12/14/2022] Open
Abstract
The review considers the molecular, cellular, organismal, and ontogenetic properties of Urodela that exhibit the highest regenerative abilities among tetrapods. The genome specifics and the expression of genes associated with cell plasticity are analyzed. The simplification of tissue structure is shown using the examples of the sensory retina and brain in mature Urodela. Cells of these and some other tissues are ready to initiate proliferation and manifest the plasticity of their phenotype as well as the correct integration into the pre-existing or de novo forming tissue structure. Without excluding other factors that determine regeneration, the pedomorphosis and juvenile properties, identified on different levels of Urodele amphibians, are assumed to be the main explanation for their high regenerative abilities. These properties, being fundamental for tissue regeneration, have been lost by amniotes. Experiments aimed at mammalian cell rejuvenation currently use various approaches. They include, in particular, methods that use secretomes from regenerating tissues of caudate amphibians and fish for inducing regenerative responses of cells. Such an approach, along with those developed on the basis of knowledge about the molecular and genetic nature and age dependence of regeneration, may become one more step in the development of regenerative medicine.
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Affiliation(s)
- Eleonora N Grigoryan
- Kol'tsov Institute of Developmental Biology, Russian Academy of Sciences, 119334 Moscow, Russia
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Liu Z, Wang R, Lin H, Liu Y. Lens regeneration in humans: using regenerative potential for tissue repairing. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1544. [PMID: 33313289 PMCID: PMC7729322 DOI: 10.21037/atm-2019-rcs-03] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The crystalline lens is an important optic element in human eyes. It is transparent and biconvex, refracting light and accommodating to form a clear retinal image. The lens originates from the embryonic ectoderm. The epithelial cells at the lens equator proliferate, elongate and differentiate into highly aligned lens fiber cells, which are the structural basis for maintaining the transparency of the lens. Cataract refers to the opacity of the lens. Currently, the treatment of cataract is to remove the opaque lens and implant an intraocular lens (IOL). This strategy is inappropriate for children younger than 2 years, because a developing eyeball is prone to have severe complications such as inflammatory proliferation and secondary glaucoma. On the other hand, the absence of the crystalline lens greatly affects visual function rehabilitation. The researchers found that mammalian lenses possess regenerative potential. We identified lens stem cells through linear tracking experiments and designed a minimally invasive lens-content removal surgery (MILS) to remove the opaque lens material while preserving the lens capsule, stem cells and microenvironment. In infants with congenital cataract, functional lens regeneration in situ can be observed after MILS, and the prognosis of visual function is better than that of traditional surgery. Because of insufficient regenerative ability in humans, the morphology and volume of the regenerated lens cannot reach the level of a normal lens. The activation, proliferation and differentiation of lens stem cells and the alignment of lens fibers are regulated by epigenetic factors, growth factors, transcription factors, immune system and other signals and their interactions. The construction of appropriate microenvironment can accelerate lens regeneration and improve its morphology. The therapeutic concept of MILS combined with microenvironment manipulation to activate endogenous stem cells for functional regeneration of organs in situ can be extended to other tissues and organs with strong self-renewal and repair ability.
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Affiliation(s)
- Zhenzhen Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Ruixin Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Haotian Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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5
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Qu P, Zuo Z, Liu Z, Niu Z, Zhang Y, Du Y, Ma X, Qiao F, Wang M, Zhang Y, Qing S, Wang Y. Sperm-borne small RNAs regulate α-tubulin acetylation and epigenetic modification of early bovine somatic cell nuclear transfer embryos. Mol Hum Reprod 2020; 25:471-482. [PMID: 31041452 DOI: 10.1093/molehr/gaz023] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 04/01/2019] [Indexed: 12/12/2022] Open
Abstract
Accumulated evidence indicates that sperm-borne small RNA plays a crucial role in embryonic development, especially the absence of the sperm-borne small RNA might be a major cause of the abnormal development of cloned embryos. In this study, we found that sperm-borne small RNA can affect abnormal pronuclear-like structures, postpone the timing of first embryo cleavage and enhance developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos. In addition, the supplementation of sperm-borne small RNA can significantly increase live birth rates and decrease the birth weights of cloned offspring. To investigate the underlying mechanisms, the levels of α-tubulin K40 acetylation (Ac α-tubulin K40) and histone H3 lysine 9 trimethylation (H3K9me3) during early embryo development were investigated in SCNT embryos with sperm-borne small RNA supplementation (termed as T-NT), compared to those normal SCNT embryos and embryos obtained from standard IVF. The results showed that sperm-borne small RNA can significantly decrease the H3K9me3 levels at the pronuclear and two-cell stages, while significantly increase Ac α-tubulin K40 levels at anaphase and telophase of bovine SCNT embryos during the first cleavage. Collectively, our study for the first time demonstrates that sperm-borne small RNA plays a crucial role in the developmental competence of SCNT embryos by regulating H3K9me3 and Ac α-tubulin K40. Further studies will be required to determine how sperm small RNA regulate the H3K9me3 and Acα-tubulin K40. Our study suggests that the supplementation of sperm-borne small RNA is a potential application to improve the cloning efficiency.
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Affiliation(s)
- Pengxiang Qu
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China.,Laboratory Animal Centre, Xi'an Jiaotong University Health Science Centre, Xi'an, Shaanxi, China
| | - Zhenzi Zuo
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Zhengqing Liu
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Zhihan Niu
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Ying Zhang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yue Du
- The Roslin Institute, University of Edinburgh, Easter Bush Campus, Midlothian, Edinburgh, UK
| | - Xiaonan Ma
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Fang Qiao
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Mengyun Wang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yong Zhang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Suzhu Qing
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Yongsheng Wang
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
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Reprogramming and transdifferentiation - two key processes for regenerative medicine. Eur J Pharmacol 2020; 882:173202. [PMID: 32562801 DOI: 10.1016/j.ejphar.2020.173202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 04/22/2020] [Accepted: 05/13/2020] [Indexed: 12/11/2022]
Abstract
Regenerative medicine based on transplants obtained from donors or foetal and new-born mesenchymal stem cells, encounter important obstacles such as limited availability of organs, ethical issues and immune rejection. The growing demand for therapeutic methods for patients being treated after serious accidents, severe organ dysfunction and an increasing number of cancer surgeries, exceeds the possibilities of the therapies that are currently available. Reprogramming and transdifferentiation provide powerful bioengineering tools. Both procedures are based on the somatic differentiated cells, which are easily and unlimitedly available, like for example: fibroblasts. During the reprogramming procedure mature cells are converted into pluripotent cells - which are capable to differentiate into almost any kind of desired cells. Transdifferentiation directly converts differentiated cells of one type into another differentiated cells type. Both procedures allow to obtained patient's dedicated cells for therapeutic purpose in regenerative medicine. In combination with biomaterials, it is possible to obtain even whole anatomical structures. Those patient's dedicated structures may serve for them upon serious accidents with massive tissue damage but also upon cancer surgeries as a replacement of damaged organ. Detailed information about reprogramming and transdifferentiation procedures as well as the current state of the art are presented in our review.
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7
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Specific activation of the hb4 gene in the Xenopus oocyte through a Nobox-binding element located at the proximal promoter sequence. ZYGOTE 2019; 27:195-202. [PMID: 31250783 DOI: 10.1017/s0967199419000017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We isolated and characterized Xenopus tropicalis hb4 flanking DNA and showed that the -3076/+29 sequence was able to drive stage-specific transcription in the developmental process. Transgenic reporter analysis indicated that green fluorescent protein was expressed in the ovaries of female frogs at 3 months of age and in both the ovaries and testis of frogs at 6 months of age. A series of experiments with deletion of the flanking sequence and a subsequent luciferase reporter assay revealed that there were two positive regulatory regions and that the most proximal sequence of the promoter region had a certain level of transcriptional activity in oocytes. Subsequently, we showed that a conserved sequence containing Nobox-binding element (NBE) was essential for transcriptional activation and that Nobox expressed in the ovary had a crucial role in hb4 transcription through the NBE sequence.
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8
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Vergara MN, Tsissios G, Del Rio-Tsonis K. Lens regeneration: a historical perspective. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2019; 62:351-361. [PMID: 29877565 PMCID: PMC6378223 DOI: 10.1387/ijdb.180084nv] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The idea of regenerating injured body parts has captivated human imagination for centuries, and the topic still remains an area of extensive scientific research. This review focuses on the process of lens regeneration: its history, our current knowledge, and the questions that remain unanswered. By highlighting some of the milestones that have shaped our understanding of this phenomenon and the contributions of scientists who have dedicated their lives to investigating these questions, we explore how regeneration enquiry evolved into the science it is today, and how technological advances accelerated our understanding of these remarkable processes.
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Affiliation(s)
- M Natalia Vergara
- Department of Ophthalmology, University of Colorado Denver School of Medicine, Aurora, CO, USA
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9
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Grigoryan EN. Molecular Factors of the Maintenance and Activation of the Juvenile Phenotype of Cellular Sources for Eye Tissue Regeneration. BIOCHEMISTRY (MOSCOW) 2018; 83:1318-1331. [DOI: 10.1134/s0006297918110032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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10
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Reid A, Tursun B. Transdifferentiation: do transition states lie on the path of development? CURRENT OPINION IN SYSTEMS BIOLOGY 2018; 11:18-23. [PMID: 30386832 PMCID: PMC6202785 DOI: 10.1016/j.coisb.2018.07.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The direct conversion of one differentiated cell fate into another identity is a process known as Transdifferentiation. During Transdifferentiation, cells pass through intermediate states that are not well understood. Given the potential application of transdifferentiation in regenerative medicine and disease modeling, a better understanding of intermediate states is crucial to avoid uncontrolled conversion or proliferation, which pose a risk for patients. Researchers have begun to analyze the transcriptomes of donor, converting and target cells of Transdifferentiation with single cell resolution to compare transitional states to those found along the path of development. Here, we review examples of Transdifferentiation in a range of model systems and organisms. We propose that cells pass either through a mixed, unspecific intermediate or progenitor-like state during Transdifferentiation, which, to varying degrees, resemble states seen during development.
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Affiliation(s)
- Anna Reid
- Berlin Institute for Medical Systems Biology, 13125 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
| | - Baris Tursun
- Berlin Institute for Medical Systems Biology, 13125 Berlin, Germany
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, 13125 Berlin, Germany
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11
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Wang QQ, Zhang YM, Zhong X, Li JW, An XR, Hou J. Dimethylated histone H3 lysine 9 is dispensable for the interaction between developmental pluripotency-associated protein 3 (Dppa3) and ten-eleven translocation 3 (Tet3) in somatic cells. Reprod Fertil Dev 2018; 31:347-356. [PMID: 30099980 DOI: 10.1071/rd18062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 07/11/2018] [Indexed: 01/15/2023] Open
Abstract
Both developmental pluripotency-associated protein 3 (Dppa3/Stella/PGC7) and dioxygenase ten-eleven translocation 3 (Tet3) are maternal factors that regulate DNA methylation reprogramming during early embryogenesis. In the mouse zygote, dimethylated histone H3 lysine 9 (H3K9me2) attracts Dppa3 to prevent Tet3-mediated oxidation of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). Here, we addressed the interplay between Dppa3 and Tet3 or H3K9me2 in somatic cells. In mouse NIH3T3 cells, the exogenously expressed Dppa3 preferentially accumulated in the cytoplasm and had no effect on Tet3-mediated 5hmC generation. In HeLa cells, the expressed Dppa3 was predominantly localised in the nucleus and could partially suppress Tet3-induced 5hmC accumulation, but this suppressive function was not correlated with H3K9me2. Co-immunoprecipitation assays further revealed an interaction of Dppa3 with Tet3 but not with H3K9me2 in HeLa cells. In cloned zygotes from somatic cells, Dppa3 distribution and 5hmC accumulation in nuclei were not affected by H3K9me2 levels. Taken together, these results suggest that H3K9me2 is not functionally associated with Dppa3 and Tet3 in somatic cells or somatic cell cloned embryos.
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Affiliation(s)
- Qian-Qian Wang
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
| | - Yu-Mei Zhang
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
| | - Xia Zhong
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
| | - Jian-Wei Li
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
| | - Xiao-Rong An
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
| | - Jian Hou
- State Key Laboratory of Agrobiotechnology and College of Biological Science, China Agricultural University, #2, Yuan-Ming-Yuan West Road, Haidian District, Beijing, 100193, China
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12
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Chromatin remodeling in Drosophila preblastodermic embryo extract. Sci Rep 2018; 8:10927. [PMID: 30026552 PMCID: PMC6053431 DOI: 10.1038/s41598-018-29129-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 06/13/2018] [Indexed: 01/06/2023] Open
Abstract
Chromatin is known to undergo extensive remodeling during nuclear reprogramming. However, the factors and mechanisms involved in this remodeling are still poorly understood and current experimental approaches to study it are not best suited for molecular and genetic analyses. Here we report on the use of Drosophila preblastodermic embryo extracts (DREX) in chromatin remodeling experiments. Our results show that incubation of somatic nuclei in DREX induces changes in chromatin organization similar to those associated with nuclear reprogramming, such as rapid binding of the germline specific linker histone dBigH1 variant to somatic chromatin, heterochromatin reorganization, changes in the epigenetic state of chromatin, and nuclear lamin disassembly. These results raise the possibility of using the powerful tools of Drosophila genetics for the analysis of chromatin changes associated with this essential process.
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13
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Russell JJ, Theriot JA, Sood P, Marshall WF, Landweber LF, Fritz-Laylin L, Polka JK, Oliferenko S, Gerbich T, Gladfelter A, Umen J, Bezanilla M, Lancaster MA, He S, Gibson MC, Goldstein B, Tanaka EM, Hu CK, Brunet A. Non-model model organisms. BMC Biol 2017; 15:55. [PMID: 28662661 PMCID: PMC5492503 DOI: 10.1186/s12915-017-0391-5] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Model organisms are widely used in research as accessible and convenient systems to study a particular area or question in biology. Traditionally only a handful of organisms have been widely studied, but modern research tools are enabling researchers to extend the set of model organisms to include less-studied and more unusual systems. This Forum highlights a range of 'non-model model organisms' as emerging systems for tackling questions across the whole spectrum of biology (and beyond), the opportunities and challenges, and the outlook for the future.
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Affiliation(s)
- James J Russell
- Department of Biology, Howard Hughes Medical Institute Stanford University, Stanford, CA, 94305, USA
| | - Julie A Theriot
- Departments of Biochemistry and of Microbiology & Immunology, Howard Hughes Medical Institute Stanford University, Stanford, CA, 94305, USA.
| | - Pranidhi Sood
- Department of Biochemistry & Biophysics, University of California San Francisco, 600 16th St, San Francisco, CA, 94158, USA
| | - Wallace F Marshall
- Department of Biochemistry & Biophysics, University of California San Francisco, 600 16th St, San Francisco, CA, 94158, USA.
| | - Laura F Landweber
- Departments of Biochemistry & Molecular Biophysics and Biological Sciences, Columbia University, New York, NY, 10032, USA
| | | | - Jessica K Polka
- Visiting Scholar, Whitehead Institute, 9 Cambridge Center, Cambridge, MA, 02142, USA
| | - Snezhana Oliferenko
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
- Randall Division of Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London, SE1 1UL, UK
| | - Therese Gerbich
- 516 Fordham Hall, University of North Carolina Chapel Hill, Chapel Hill, NC, 27514, USA
| | - Amy Gladfelter
- 516 Fordham Hall, University of North Carolina Chapel Hill, Chapel Hill, NC, 27514, USA
| | - James Umen
- Donald Danforth Plant Science Center, 975 N. Warson Rd, St. Louis, MO, 63132, USA
| | | | - Madeline A Lancaster
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, CB2 0QH, Cambridge, UK
| | - Shuonan He
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
| | - Matthew C Gibson
- Stowers Institute for Medical Research, Kansas City, MO, 64110, USA
- Department of Anatomy and Cell Biology, The University of Kansas School of Medicine, Kansas City, KS, 66160, USA
| | - Bob Goldstein
- Biology Department, The University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Elly M Tanaka
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus Vienna Biocenter 1, 1030, Vienna, Austria
| | - Chi-Kuo Hu
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
| | - Anne Brunet
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
- Glenn Laboratories for the Biology of Aging at Stanford, Stanford, CA, 94305, USA
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14
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Grigoryan EN, Markitantova YV. Cellular and Molecular Preconditions for Retinal Pigment Epithelium (RPE) Natural Reprogramming during Retinal Regeneration in Urodela. Biomedicines 2016; 4:E28. [PMID: 28536395 PMCID: PMC5344269 DOI: 10.3390/biomedicines4040028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 11/26/2016] [Accepted: 11/26/2016] [Indexed: 12/25/2022] Open
Abstract
Many regeneration processes in animals are based on the phenomenon of cell reprogramming followed by proliferation and differentiation in a different specialization direction. An insight into what makes natural (in vivo) cell reprogramming possible can help to solve a number of biomedical problems. In particular, the first problem is to reveal the intrinsic properties of the cells that are necessary and sufficient for reprogramming; the second, to evaluate these properties and, on this basis, to reveal potential endogenous sources for cell substitution in damaged tissues; and the third, to use the acquired data for developing approaches to in vitro cell reprogramming in order to obtain a cell reserve for damaged tissue repair. Normal cells of the retinal pigment epithelium (RPE) in newts (Urodela) can change their specialization and transform into retinal neurons and ganglion cells (i.e., actualize their retinogenic potential). Therefore, they can serve as a model that provides the possibility to identify factors of the initial competence of vertebrate cells for reprogramming in vivo. This review deals mainly with the endogenous properties of native newt RPE cells themselves and, to a lesser extent, with exogenous mechanisms regulating the process of reprogramming, which are actively discussed.
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Affiliation(s)
- Eleonora N Grigoryan
- Kol'tsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow 119334, Russia.
| | - Yuliya V Markitantova
- Kol'tsov Institute of Developmental Biology, Russian Academy of Sciences, Moscow 119334, Russia.
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15
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Grigoryan EN. High regenerative ability of tailed amphibians (Urodela) as a result of the expression of juvenile traits by mature animals. Russ J Dev Biol 2016. [DOI: 10.1134/s1062360416020041] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Adult cell plasticity in vivo: de-differentiation and transdifferentiation are back in style. Nat Rev Mol Cell Biol 2016; 17:413-25. [PMID: 26979497 DOI: 10.1038/nrm.2016.24] [Citation(s) in RCA: 281] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Biologists have long been intrigued by the possibility that cells can change their identity, a phenomenon known as cellular plasticity. The discovery that terminally differentiated cells can be experimentally coaxed to become pluripotent has invigorated the field, and recent studies have demonstrated that changes in cell identity are not limited to the laboratory. Specifically, certain adult cells retain the capacity to de-differentiate or transdifferentiate under physiological conditions, as part of an organ's normal injury response. Recent studies have highlighted the extent to which cell plasticity contributes to tissue homeostasis, findings that have implications for cell-based therapy.
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17
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Ghosh S. Human regeneration: An achievable goal or a dream? J Biosci 2016; 41:157-65. [PMID: 26949097 DOI: 10.1007/s12038-016-9589-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The main objective of regenerative medicine is to replenish cells or tissues or even to restore different body parts that are lost or damaged due to disease, injury and aging. Several avenues have been explored over many decades to address the fascinating problem of regeneration at the cell, tissue and organ levels. Here we discuss some of the primary approaches adopted by researchers in the context of enhancing the regenerating ability of mammals. Natural regeneration can occur in different animal species, and the underlying mechanism is highly relevant to regenerative medicine-based intervention. Significant progress has been achieved in understanding the endogenous regeneration in urodeles and fishes with the hope that they could help to reach our goal of designing future strategies for human regeneration.
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Affiliation(s)
- Sukla Ghosh
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, A. P.C. Road, Kolkata 700 009, India,
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Pérez-Montero S, Carbonell A, Azorín F. Germline-specific H1 variants: the "sexy" linker histones. Chromosoma 2015; 125:1-13. [PMID: 25921218 DOI: 10.1007/s00412-015-0517-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 04/14/2015] [Accepted: 04/15/2015] [Indexed: 01/07/2023]
Abstract
The eukaryotic genome is packed into chromatin, a nucleoprotein complex mainly formed by the interaction of DNA with the abundant basic histone proteins. The fundamental structural and functional subunit of chromatin is the nucleosome core particle, which is composed by 146 bp of DNA wrapped around an octameric protein complex formed by two copies of each core histone H2A, H2B, H3, and H4. In addition, although not an intrinsic component of the nucleosome core particle, linker histone H1 directly interacts with it in a monomeric form. Histone H1 binds nucleosomes near the exit/entry sites of linker DNA, determines nucleosome repeat length and stabilizes higher-order organization of nucleosomes into the ∼30 nm chromatin fiber. In comparison to core histones, histone H1 is less well conserved through evolution. Furthermore, histone H1 composition in metazoans is generally complex with most species containing multiple variants that play redundant as well as specific functions. In this regard, a characteristic feature is the presence of specific H1 variants that replace somatic H1s in the germline and during early embryogenesis. In this review, we summarize our current knowledge about their structural and functional properties.
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Affiliation(s)
- Salvador Pérez-Montero
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028, Barcelona, Spain.,Institute for Research in Biomedicine, IRB Barcelona, Baldiri Reixac, 10, 08028, Barcelona, Spain
| | - Albert Carbonell
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028, Barcelona, Spain.,Institute for Research in Biomedicine, IRB Barcelona, Baldiri Reixac, 10, 08028, Barcelona, Spain
| | - Fernando Azorín
- Institute of Molecular Biology of Barcelona, CSIC, Baldiri Reixac, 4, 08028, Barcelona, Spain. .,Institute for Research in Biomedicine, IRB Barcelona, Baldiri Reixac, 10, 08028, Barcelona, Spain.
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Maki N. Newt lens transdifferentiation: from lentectomy to immuno-FISH. Methods Mol Biol 2015; 1290:81-9. [PMID: 25740478 DOI: 10.1007/978-1-4939-2495-0_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Newt lens regeneration is achieved by a unique cellular regulation of transdifferentiation where the dorsal iris pigmented epithelial cells (PECs) dedifferentiate and redifferentiate into lens cells. Recent studies have shown that nuclear architecture of PECs is dynamically changed and unique epigenetic regulation in somatic nucleus is crucial in the lens transdifferentiation. Immuno-FISH, detection of protein and gene loci in nucleus, is one of the effective tools to analyze nuclear architecture of PECs. In this chapter a whole process from lentectomy to immuno-FISH is described.
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Affiliation(s)
- Nobuyasu Maki
- Institute of Protein Research, Osaka University, 3-2 Yamadaoka, Suita-Shi, Osaka, 565-0871, Japan,
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20
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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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Godwin J. The promise of perfect adult tissue repair and regeneration in mammals: Learning from regenerative amphibians and fish. Bioessays 2014; 36:861-71. [DOI: 10.1002/bies.201300144] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- James Godwin
- The Australian Regenerative Medicine Institute (ARMI); Monash University; Clayton Victoria Australia
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Ferguson DP, Dangott LJ, Lightfoot JT. Lessons learned from vivo-morpholinos: How to avoid vivo-morpholino toxicity. Biotechniques 2014; 56:251-6. [PMID: 24806225 DOI: 10.2144/000114167] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 03/26/2014] [Indexed: 11/23/2022] Open
Abstract
Vivo-morpholinos are a promising tool for gene silencing. These oligonucleotide analogs transiently silence genes by blocking either translation or pre-mRNA splicing. Little to no toxicity has been reported for vivo-morpholino treatment. However, in a recent study conducted in our lab, treatment of mice with vivo-morpholinos resulted in high mortality rates. We hypothesized that the deaths were the result of oligonucleotide hybridization, causing an increased cationic charge associated with the dendrimer delivery moiety of the vivo-morpholino. The cationic charge increased blood clot formation in whole blood treated with vivo-morpholinos, suggesting that clotting could have caused cardiac arrest in the deceased mice. Therefore, we investigate the mechanism by which some vivo-morpholinos increase mortality rates and propose techniques to alleviate vivo-morpholino toxicity.
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Affiliation(s)
- David P Ferguson
- Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX; Biology of Physical Activity Laboratory, Dept. of Health & Kinesiology, Texas A&M University, College Station, TX
| | - Lawrence J Dangott
- Protein Chemistry Laboratory, Dept. of Biochemistry/Biophysics, Texas A&M University, College Station, TX
| | - J Timothy Lightfoot
- Biology of Physical Activity Laboratory, Dept. of Health & Kinesiology, Texas A&M University, College Station, TX
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Abstract
During newt lens regeneration a unique transdifferentiation event occurs. In this process, dorsal iris pigmented epithelial cells transdifferentiate into lens cells. This system should provide a new insight into cellular plasticity in basic and applied research. Recently, a series of approaches to study epigenetic reprogramming during transdifferentiation have been performed. In this review, we introduce the regulation of dynamic regulation of core-histone modifications and the emergence of an oocyte-type linker histone during transdifferentiation. Finally, we show supporting evidence that there are common strategies of reprogramming between newt somatic cell in transdifferentiation and oocytes after somatic cell nuclear transfer.
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Affiliation(s)
- Nobuyasu Maki
- Institute of Protein Research, Osaka University, Osaka, Japan.
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Ferguson DP, Schmitt EE, Lightfoot JT. Vivo-morpholinos induced transient knockdown of physical activity related proteins. PLoS One 2013; 8:e61472. [PMID: 23630592 PMCID: PMC3632599 DOI: 10.1371/journal.pone.0061472] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 03/13/2013] [Indexed: 11/19/2022] Open
Abstract
Physical activity is associated with disease prevention and overall wellbeing. Additionally there has been evidence that physical activity level is a result of genetic influence. However, there has not been a reliable method to silence candidate genes in vivo to determine causal mechanisms of physical activity regulation. Vivo-morpholinos are a potential method to transiently silence specific genes. Thus, the aim of this study was to validate the use of Vivo-morpholinos in a mouse model for voluntary physical activity with several sub-objectives. We observed that Vivo-morpholinos achieved between 60–97% knockdown of Drd1-, Vmat2-, and Glut4-protein in skeletal muscle, the delivery moiety of Vivo-morpholinos (scramble) did not influence physical activity and that a cocktail of multiple Vivo-morpholinos can be given in a single treatment to achieve protein knockdown of two different targeted proteins in skeletal muscle simultaneously. Knocking down Drd1, Vmat2, or Glut4 protein in skeletal muscle did not affect physical activity. Vivo-morpholinos injected intravenously alone did not significantly knockdown Vmat2-protein expression in the brain (p = 0.28). However, the use of a bradykinin analog to increase blood-brain-barrier permeability in conjunction with the Vivo-morpholinos significantly (p = 0.0001) decreased Vmat2-protein in the brain with a corresponding later over-expression of Vmat2 coincident with a significant (p = 0.0016) increase in physical activity. We conclude that Vivo-morpholinos can be a valuable tool in determining causal gene-phenotype relationships in whole animal models.
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Affiliation(s)
- David P Ferguson
- Department of Health and Kinesiology, Texas A&M University, College Station, Texas, United States of America.
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Abstract
Comparative studies of lens and retina regeneration have been conducted within a wide variety of animals over the last 100 years. Although amphibians, fish, birds and mammals have all been noted to possess lens- or retina-regenerative properties at specific developmental stages, lens or retina regeneration in adult animals is limited to lower vertebrates. The present review covers the newest perspectives on lens and retina regeneration from these different model organisms with a focus on future trends in regeneration research.
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Havasi A, Haegele JA, Gall JM, Blackmon S, Ichimura T, Bonegio RG, Panchenko MV. Histone acetyl transferase (HAT) HBO1 and JADE1 in epithelial cell regeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 182:152-62. [PMID: 23159946 DOI: 10.1016/j.ajpath.2012.09.017] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Revised: 09/09/2012] [Accepted: 09/20/2012] [Indexed: 12/31/2022]
Abstract
HBO1 acetylates lysine residues of histones and is involved in DNA replication and gene transcription. Two isoforms of JADE1, JADE1S and JADE1L, bind HBO1 and promote acetylation of histones in chromatin context. We characterized the role of JADE1-HBO1 complexes in vitro and in vivo during epithelial cell replication. Down-regulation of JADE1 by siRNA diminished the rate of DNA synthesis in cultured cells, decreased endogenous HBO1 protein expression, and prevented chromatin recruitment of replication factor Mcm7, demonstrating that JADE1 is required for cell proliferation. We used a murine model of acute kidney injury to examine expression of HBO1-JADE1S/L in injured and regenerating epithelial tissue. In control kidneys, JADE1S, JADE1L, and HBO1 were expressed in nuclei of proximal and distal tubular epithelial cells. Ischemia and reperfusion injury resulted in an initial decrease in JADE1S, JADE1L, and HBO1 protein levels, which returned to baseline during renal recovery. HBO1 and JADE1S recovered as cell proliferation reached its maximum, whereas JADE1L recovered after bulk proliferation had ceased. The temporal expression of JADE1S correlated with the acetylation of histone H4 on lysines 5 and 12, but not with acetylation of histone H3 on lysine 14, demonstrating that the JADE1S-HBO1 complex specifically marks H4 during epithelial cell proliferation. These data implicate JADE1-HBO1 complex in acute kidney injury and suggest distinct roles for JADE1 isoforms during epithelial cell recovery.
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Affiliation(s)
- Andrea Havasi
- Department of Pathology, Boston University School of Medicine, Boston, Massachusetts 02118, USA
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Regeneration and reprogramming. Curr Opin Genet Dev 2012; 22:485-93. [PMID: 23084810 DOI: 10.1016/j.gde.2012.09.006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 08/24/2012] [Accepted: 09/17/2012] [Indexed: 01/14/2023]
Abstract
Recent reprogramming studies indicate that mammalian, somatic cells have the potential to achieve pluripotent states and undergo cell type switching. Such cellular traits are observed under natural conditions in animals that regenerate complex organs. A number of invertebrates display the amazing trait of whole body regeneration. Underlying this trait is the maintenance of pluripotent cells in somatic tissue, and molecular studies indicate the use of common players associated with pluripotency and germ cell properties between these invertebrates and mammalian pluripotent cells. In regenerative vertebrates, heart regeneration, lens regeneration, and retinal regeneration provide good examples of dedifferentiation and transdifferentiation. The molecular factors associated with these phenomena are discussed.
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Rodriguez-Osorio N, Urrego R, Cibelli JB, Eilertsen K, Memili E. Reprogramming mammalian somatic cells. Theriogenology 2012; 78:1869-86. [PMID: 22979962 DOI: 10.1016/j.theriogenology.2012.05.030] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Revised: 05/20/2012] [Accepted: 05/31/2012] [Indexed: 01/23/2023]
Abstract
Somatic cell nuclear transfer (SCNT), the technique commonly known as cloning, permits transformation of a somatic cell into an undifferentiated zygote with the potential to develop into a newborn animal (i.e., a clone). In somatic cells, chromatin is programmed to repress most genes and express some, depending on the tissue. It is evident that the enucleated oocyte provides the environment in which embryonic genes in a somatic cell can be expressed. This process is controlled by a series of epigenetic modifications, generally referred to as "nuclear reprogramming," which are thought to involve the removal of reversible epigenetic changes acquired during cell differentiation. A similar process is thought to occur by overexpression of key transcription factors to generate induced pluripotent stem cells (iPSCs), bypassing the need for SCNT. Despite its obvious scientific and medical importance, and the great number of studies addressing the subject, the molecular basis of reprogramming in both reprogramming strategies is largely unknown. The present review focuses on the cellular and molecular events that occur during nuclear reprogramming in the context of SCNT and the various approaches currently being used to improve nuclear reprogramming. A better understanding of the reprogramming mechanism will have a direct impact on the efficiency of current SCNT procedures, as well as iPSC derivation.
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Inoue T, Inoue R, Tsutsumi R, Tada K, Urata Y, Michibayashi C, Takemura S, Agata K. Lens regenerates by means of similar processes and timeline in adults and larvae of the newt Cynops pyrrhogaster. Dev Dyn 2012; 241:1575-83. [PMID: 22930574 DOI: 10.1002/dvdy.23854] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/09/2012] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND It is widely accepted that juvenile animals can regenerate faster than adults. For example, in the case of lens regeneration of the newt Cynops pyrrhogaster, larvae and adults require approximately 30 and 80 days for completion of lens regeneration, respectively. However, when we carefully observed lens regeneration in C. pyrrhogaster at the cellular level using molecular markers in the present study, we found that lens regeneration during the larval stage proceeded at similar speed and by means of similar steps to those in adults. RESULTS We could not find any drastic difference between regeneration at these two stages, except that the size of the eyes was very different. CONCLUSIONS Our observations suggested that larvae could regenerate a lens of the original size within a shorter time than adults because the larval lens was smaller than the adult lens, but the speed of regeneration was not faster in larvae. In addition, by repeatedly observing the regeneration in one individual transgenic newt that expressed fluorescence specifically in lens fiber cells in vivo and comparing the regeneration process at the embryonic, larval, and postmetamorphosis stages, we confirmed that the regeneration speed was the same at each of these stages in the same individual.
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Affiliation(s)
- Takeshi Inoue
- Department of Biophysics, Graduate School of Science, Kyoto University, Kyoto, Japan.
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Zhu W, Kuo D, Nathanson J, Satoh A, Pao GM, Yeo GW, Bryant SV, Voss SR, Gardiner DM, Hunter T. Retrotransposon long interspersed nucleotide element-1 (LINE-1) is activated during salamander limb regeneration. Dev Growth Differ 2012; 54:673-85. [PMID: 22913491 DOI: 10.1111/j.1440-169x.2012.01368.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 06/20/2012] [Accepted: 07/01/2012] [Indexed: 12/14/2022]
Abstract
Salamanders possess an extraordinary capacity for tissue and organ regeneration when compared to mammals. In our effort to characterize the unique transcriptional fingerprint emerging during the early phase of salamander limb regeneration, we identified transcriptional activation of some germline-specific genes within the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells into a germline-like state. In this work, we focus on one of these genes, the long interspersed nucleotide element-1 (LINE-1) retrotransposon, which is usually active in germ cells and silent in most of the somatic tissues in other organisms. LINE-1 was found to be dramatically upregulated during regeneration. In addition, higher genomic LINE-1 content was also detected in the limb regenerate when compared to that before amputation indicating that LINE-1 retrotransposition is indeed active during regeneration. Active LINE-1 retrotransposition has been suggested to have a potentially deleterious impact on genomic integrity. Silencing of activated LINE-1 by small RNAs has been reported to be part of the machinery aiming to maintain genomic integrity. Indeed, we were able to identify putative LINE-1-related piRNAs in the limb blastema. Transposable element-related piRNAs have been identified frequently in the germline in other organisms. Thus, we present here a scenario in which a unique germline-like state is established during axolotl limb regeneration, and the re-activation of LINE-1 may serve as a marker for cellular dedifferentiation in the early-stage of limb regeneration.
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Affiliation(s)
- Wei Zhu
- Molecular and Cell Biology Laboratory and Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
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Zhu W, Pao GM, Satoh A, Cummings G, Monaghan JR, Harkins TT, Bryant SV, Randal Voss S, Gardiner DM, Hunter T. Activation of germline-specific genes is required for limb regeneration in the Mexican axolotl. Dev Biol 2012; 370:42-51. [PMID: 22841627 DOI: 10.1016/j.ydbio.2012.07.021] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 07/03/2012] [Accepted: 07/10/2012] [Indexed: 11/30/2022]
Abstract
The capacity for tissue and organ regeneration in humans is dwarfed by comparison to that of salamanders. Emerging evidence suggests that mechanisms learned from the early phase of salamander limb regeneration-wound healing, cellular dedifferentiation and blastemal formation-will reveal therapeutic approaches for tissue regeneration in humans. Here we describe a unique transcriptional fingerprint of regenerating limb tissue in the Mexican axolotl (Ambystoma mexicanum) that is indicative of cellular reprogramming of differentiated cells to a germline-like state. Two genes that are required for self-renewal of germ cells in mice and flies, Piwi-like 1 (PL1) and Piwi-like 2 (PL2), are expressed in limb blastemal cells, the basal layer keratinocytes and the thickened apical epithelial cap in the wound epidermis in the regenerating limb. Depletion of PL1 and PL2 by morpholino oligonucleotides decreased cell proliferation and increased cell death in the blastema leading to a significant retardation of regeneration. Examination of key molecules that are known to be required for limb development or regeneration further revealed that FGF8 is transcriptionally downregulated in the presence of the morpholino oligos, indicating PL1 and PL2 might participate in FGF signaling during limb regeneration. Given the requirement for FGF signaling in limb development and regeneration, the results suggest that PL1 and PL2 function to establish a unique germline-like state that is associated with successful regeneration.
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Affiliation(s)
- Wei Zhu
- Salk Institute for Biological Studies, La Jolla, CA 92037, USA
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32
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Ooi J, Liu P. Delineating nuclear reprogramming. Protein Cell 2012; 3:329-45. [PMID: 22467264 DOI: 10.1007/s13238-012-2920-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Accepted: 02/04/2012] [Indexed: 12/13/2022] Open
Abstract
Nuclear reprogramming is described as a molecular switch, triggered by the conversion of one cell type to another. Several key experiments in the past century have provided insight into the field of nuclear reprogramming. Previously deemed impossible, this research area is now brimming with new findings and developments. In this review, we aim to give a historical perspective on how the notion of nuclear reprogramming was established, describing main experiments that were performed, including (1) somatic cell nuclear transfer, (2) exposure to cell extracts and cell fusion, and (3) transcription factor induced lineage switch. Ultimately, we focus on (4) transcription factor induced pluripotency, as initiated by a landmark discovery in 2006, where the process of converting somatic cells to a pluripotent state was narrowed down to four transcription factors. The conception that somatic cells possess the capacity to revert to an immature status brings about huge clinical implications including personalized therapy, drug screening and disease modeling. Although this technology has potential to revolutionize the medical field, it is still impeded by technical and biological obstacles. This review describes the effervescent changes in this field, addresses bottlenecks hindering its advancement and in conclusion, applies the latest findings to overcome these issues.
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Affiliation(s)
- Jolene Ooi
- Wellcome Trust Sanger Institute, Hinxton CB10 1SA, UK
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Abstract
Mammalian preimplantation development is a process of dedifferentiation from the terminally differentiated eggs to the totipotent blastomeres at the cleavage stage, and then to the pluripotent cells at the blastocyst stage. Maternal factors that accumulate during oogenesis dominate early preimplantation development until the embryonic factors gain control after the activation of the embryonic genome. Recently, a handful of maternal factors that are encoded by the maternal-effect genes have been characterized in genetically modified mouse models. These factors are shown to participate in many aspects of preimplantation development, such as the degradation of maternal macromolecues, epigenetic modification, protein translation, cellular signaling transduction, and cell compaction. Even so, little is known about the interactions between different maternal factors. In this chapter, we have summarized the functions of known maternal factors and hopefully this will lead to a better understanding of the regulation of preimplantation embryogenesis by the maternal regulatory network.
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Affiliation(s)
- Wenjing Zheng
- Department of Cell and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
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Notch EG, Shaw JR, Coutermarsh BA, Dzioba M, Stanton BA. Morpholino gene knockdown in adult Fundulus heteroclitus: role of SGK1 in seawater acclimation. PLoS One 2011; 6:e29462. [PMID: 22216285 PMCID: PMC3245286 DOI: 10.1371/journal.pone.0029462] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 11/29/2011] [Indexed: 11/21/2022] Open
Abstract
The Atlantic killifish (Fundulus heteroclitus) is an environmental sentinel organism used extensively for studies on environmental toxicants and salt (NaCl) homeostasis. Previous research in our laboratory has shown that rapid acclimation of killifish to seawater is mediated by trafficking of CFTR chloride channels from intracellular vesicles to the plasma membrane in the opercular membrane within the first hour in seawater, which enhances chloride secretion into seawater, thereby contributing to salt homeostasis. Acute transition to seawater is also marked by an increase in both mRNA and protein levels of serum glucocorticoid kinase 1 (SGK1) within 15 minutes of transfer. Although the rise in SGK1 in gill and its functional analog, the opercular membrane, after seawater transfer precedes the increase in membrane CFTR, a direct role of SGK1 in elevating membrane CFTR has not been established in vivo. To test the hypothesis that SGK1 mediates the increase in plasma membrane CFTR we designed two functionally different vivo-morpholinos to knock down SGK1 in gill, and developed and validated a vivo-morpholino knock down technique for adult killifish. Injection (intraperitoneal, IP) of the splice blocking SGK1 vivo-morpholino reduced SGK1 mRNA in the gill after transition from fresh to seawater by 66%. The IP injection of the translational blocking and splice blocking vivo-morpholinos reduced gill SGK1 protein abundance in fish transferred from fresh to seawater by 64% and 53%, respectively. Moreover, knock down of SGK1 completely eliminated the seawater induced rise in plasma membrane CFTR, demonstrating that the increase in SGK1 protein is required for the trafficking of CFTR from intracellular vesicles in mitochondrion rich cells to the plasma membrane in the gill during acclimation to seawater. This is the first report of the use of vivo-morpholinos in adult killifish and demonstrates that vivo-morpholinos are a valuable genetic tool for this environmentally relevant model organism.
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Affiliation(s)
- Emily G Notch
- Department of Microbiology and Immunology and of Physiology, Dartmouth Medical School, Hanover, New Hampshire, USA.
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36
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Bhavsar RB, Nakamura K, Tsonis PA. A system for culturing iris pigment epithelial cells to study lens regeneration in newt. J Vis Exp 2011:2713. [PMID: 21730940 PMCID: PMC3197043 DOI: 10.3791/2713] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Salamanders like newt and axolotl possess the ability to regenerate many of its lost body parts such as limbs, the tail with spinal cord, eye, brain, heart, the jaw 1. Specifically, newts are unique for its lens regeneration capability. Upon lens removal, IPE cells of the dorsal iris transdifferentiate to lens cells and eventually form a new lens in about a month 2,3. This property of regeneration is never exhibited by the ventral iris cells. The regeneration potential of the iris cells can be studied by making transplants of the in vitro cultured IPE cells. For the culture, the dorsal and ventral iris cells are first isolated from the eye and cultured separately for a time period of 2 weeks (Figure 1). These cultured cells are reaggregated and implanted back to the newt eye. Past studies have shown that the dorsal reaggregate maintains its lens forming capacity whereas the ventral aggregate does not form a lens, recapitulating, thus the in vivo process (Figure 2) 4,5. This system of determining regeneration potential of dorsal and ventral iris cells is very useful in studying the role of genes and proteins involved in lens regeneration.
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Sotillo E, Thomas-Tikhonenko A. Shielding the messenger (RNA): microRNA-based anticancer therapies. Pharmacol Ther 2011; 131:18-32. [PMID: 21514318 DOI: 10.1016/j.pharmthera.2011.04.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2011] [Accepted: 03/29/2011] [Indexed: 02/08/2023]
Abstract
It has been a decade since scientists realized that microRNAs (miRNAs) are not an oddity invented by worms to regulate gene expression at post-transcriptional levels. Rather, many of these 21-22-nucleotide-short RNAs exist in invertebrates and vertebrates alike and some of them are in fact highly conserved. miRNAs are now recognized as an important class of non-coding small RNAs that inhibit gene expression by targeting mRNA stability and translation. In the last ten years, our knowledge of the miRNAs world was expanding at vertiginous speed, propelled by the development of computational engines for miRNA identification and target prediction, biochemical tools and techniques to modulate miRNA activity, and last but not least, the emergence of miRNA-centric animal models. One important conclusion that has emerged from this effort is that many microRNAs and their cognate targets are strongly implicated in cancer, either as oncogenes or tumor and metastasis suppressors. In this review we will discuss the diverse role that miRNAs play in cancer initiation and progression and also the tools with which miRNA expression could be corrected in vivo. While the idea of targeting microRNAs towards therapeutic ends is getting considerable traction, basic, translational, and clinical research done in the next few years will tell whether this promise is well-founded.
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Affiliation(s)
- Elena Sotillo
- Division of Cancer Pathobiology, Department of Pathology & Laboratory Medicine, The Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA, USA
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Abstract
Here we describe a protocol for gene loss of function during regeneration in newts, specifically applied to lens regeneration. Knockdown with the use of morpholinos can be achieved both in vitro and in vivo, depending on the experimental design. These methods achieve desirable levels of gene knockdown, and thus can be compared with methods developed for use in other animals, such as zebrafish. The technology has been applied to study molecular mechanisms during the process of lens regeneration by knocking down genes at specific stages and examining their effects on other genes and lens differentiation. The protocol can take a few days or up to 20 d to complete, depending on the duration of the experiment.
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Sugimoto K, Gordon SP, Meyerowitz EM. Regeneration in plants and animals: dedifferentiation, transdifferentiation, or just differentiation? Trends Cell Biol 2011; 21:212-8. [DOI: 10.1016/j.tcb.2010.12.004] [Citation(s) in RCA: 208] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/30/2010] [Accepted: 12/10/2010] [Indexed: 01/17/2023]
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