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Pérez-Maldonado MA, González-González XA, Chimal-Monroy J, Marín-Llera JC. Influence of DNA-methylation at multiple stages of limb chondrogenesis. Dev Biol 2024; 512:1-10. [PMID: 38657748 DOI: 10.1016/j.ydbio.2024.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 04/05/2024] [Accepted: 04/18/2024] [Indexed: 04/26/2024]
Abstract
Precise regulation of gene expression is of utmost importance during cell fate specification. DNA methylation is a key epigenetic mechanism that plays a significant role in the regulation of cell fate by recruiting repression proteins or inhibiting the binding of transcription factors to DNA to regulate gene expression. Limb development is a well-established model for understanding cell fate decisions, and the formation of skeletal elements is coordinated through a sequence of events that control chondrogenesis spatiotemporally. It has been established that epigenetic control participates in cartilage maturation. However, further investigation is required to determine its role in the earliest stages of chondrocyte differentiation. This study investigates how the DNA methylation environment affects cell fate divergence during the early chondrogenic events. Our research has shown for the first time that inhibiting DNA methylation in interdigital tissue with 5-azacytidine results in the formation of an ectopic digit. This discovery suggested that DNA methylation dynamics could regulate the fate of cells between chondrogenesis and cell death during autopod development. Our in vitro findings indicate that DNA methylation at the early stages of chondrogenesis is integral in regulating condensation by controlling cell adhesion and proapoptotic genes. As a result, the dynamics of methylation and demethylation are crucial in governing chondrogenesis and cell death during different stages of limb chondrogenesis.
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Affiliation(s)
- Mario Alberto Pérez-Maldonado
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228, Ciudad de México, 04510, México
| | - Ximena Alexandra González-González
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228, Ciudad de México, 04510, México
| | - Jesús Chimal-Monroy
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228, Ciudad de México, 04510, México.
| | - Jessica Cristina Marín-Llera
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Apartado Postal 70228, Ciudad de México, 04510, México.
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2
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Tokita M, Matsushita H, Asakura Y. Developmental mechanisms underlying webbed foot morphological diversity in waterbirds. Sci Rep 2020; 10:8028. [PMID: 32415088 PMCID: PMC7229147 DOI: 10.1038/s41598-020-64786-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 04/20/2020] [Indexed: 11/20/2022] Open
Abstract
The webbed feet of waterbirds are morphologically diverse and classified into four types: the palmate foot, semipalmate foot, totipalmate foot, and lobate foot. To understand the developmental mechanisms underlying this morphological diversity, we conducted a series of comparative analyses. Ancestral state reconstruction based on phylogeny assumed that the lobate feet possessed by the common coot and little grebe arose independently, perhaps through distinct developmental mechanisms. Gremlin1, which encodes a bone morphogenetic protein (BMP) antagonist and inhibits interdigital cell death (ICD) in the foot plate of avian embryos, remained expressed in the interdigital tissues of webbed feet in the duck, common coot, little grebe, and great cormorant. Differences in Gremlin1 expression pattern and proliferating cell distribution pattern in the toe tissues of the common coot and little grebe support the convergent evolution of lobate feet. In the totipalmate-footed great cormorant, Gremlin1 was expressed in all interdigital tissues at St. 31, but its expression disappeared except along the toes by St. 33. The webbing of the cormorant's totipalmate foot and duck's palmate foot may have risen from distinct developmental mechanisms.
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Affiliation(s)
- Masayoshi Tokita
- Department of Biology, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan.
| | - Hiroya Matsushita
- Department of Biology, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan
- Department of Polar Science, SOKENDAI (The Graduate University for Advanced Studies), 10-3 Midori-machi, Tachikawa, Tokyo, 190-8518, Japan
| | - Yuya Asakura
- Department of Biology, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba, 274-8510, Japan
- Graduate School of Bioscience and Biotechnology, Fukui Prefectural University, 4-1-1 Kenjojima, Matsuoka, Eiheiji-cho, Fukui, 910-1195, Japan
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3
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Ouyang C, Mu J, Lu Q, Li J, Zhu H, Wang Q, Zou MH, Xie Z. Autophagic degradation of KAT2A/GCN5 promotes directional migration of vascular smooth muscle cells by reducing TUBA/α-tubulin acetylation. Autophagy 2019; 16:1753-1770. [PMID: 31878840 DOI: 10.1080/15548627.2019.1707488] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Macroautophagy/autophagy, a fundamental process for degradation of macromolecules and organelles, occurs constitutively at a basal level and is upregulated in response to stress. Whether autophagy regulates protein acetylation and microtubule stability in vascular smooth muscle cells (VSMCs) migration, however, remains unknown. Here, we demonstrate that the histone acetyltransferase KAT2A/GCN5 (lysine acetyltransferase 2) binds directly to the autophagosome protein MAP1LC3/LC3 (microtubule associated protein 1 light chain 3) via a conserved LC3-interacting region (LIR) domain. This interaction is required for KAT2A sequestration in autophagosomes and degradation by lysosomal acid hydrolases. Suppression of autophagy results in KAT2A accumulation. KAT2A functions as an acetyltransferase to increase TUBA/α-tubulin acetylation, promote microtubule polymerization and stability, ultimately inhibiting directional cell migration. Our findings indicate that deacetylation of TUBA and perturbation of microtubule stability via selective autophagic degradation of KAT2A are essential for autophagy-promoting VSMC migration. Abbreviations: ACTB: actin beta; ATAT1: alpha tubulin acetyltransferase 1; ATG: autophagy-related; BECN1: beclin 1; CQ: chloroquine; FBS: fetal bovine serum; GST: glutathione S-transferase; H4K16ac: histone H4 lysine 16 acetylation; HASMCs: human aortic smooth muscle cells; HBSS: Hank's buffered salt solution; HDAC6: histone deacetylase 6; hMOF: human males absent on the first; IP: immunoprecipitation; KAT2A/GCN5: lysine acetyltransferase 2A; Lacta: lactacystin; LIR: LC3-interaction region; MAP1LC3: microtubule associated protein 1 light chain 3; MEFs: mouse embryonic fibroblasts; MTOC: microtubule-organizing center; PE: phosphatidylethanolamine; PtdIns3K: class III phosphatidylinositol 3-kinase; RUNX2: runt-related transcription factor 2; SIRT1: sirtuin 1; SIRT2: sirtuin 2; SQSTM1/p62: sequestosome 1; ULK1: unc-51 like autophagy activating kinase 1; VSMCs: vascular smooth muscle cells; WT: wild-type.
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Affiliation(s)
- Changhan Ouyang
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Jing Mu
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Qiulun Lu
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Jian Li
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Huaiping Zhu
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Qilong Wang
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Ming-Hui Zou
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
| | - Zhonglin Xie
- Center of Molecular and Translational Medicine, Georgia State University , Atlanta, GA, USA
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MacFarlane EG, Haupt J, Dietz HC, Shore EM. TGF-β Family Signaling in Connective Tissue and Skeletal Diseases. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a022269. [PMID: 28246187 DOI: 10.1101/cshperspect.a022269] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The transforming growth factor β (TGF-β) family of signaling molecules, which includes TGF-βs, activins, inhibins, and numerous bone morphogenetic proteins (BMPs) and growth and differentiation factors (GDFs), has important functions in all cells and tissues, including soft connective tissues and the skeleton. Specific TGF-β family members play different roles in these tissues, and their activities are often balanced with those of other TGF-β family members and by interactions with other signaling pathways. Perturbations in TGF-β family pathways are associated with numerous human diseases with prominent involvement of the skeletal and cardiovascular systems. This review focuses on the role of this family of signaling molecules in the pathologies of connective tissues that manifest in rare genetic syndromes (e.g., syndromic presentations of thoracic aortic aneurysm), as well as in more common disorders (e.g., osteoarthritis and osteoporosis). Many of these diseases are caused by or result in pathological alterations of the complex relationship between the TGF-β family of signaling mediators and the extracellular matrix in connective tissues.
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Affiliation(s)
- Elena Gallo MacFarlane
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
| | - Julia Haupt
- Department of Orthopedic Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104.,Center for Research in FOP and Related Disorders, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Harry C Dietz
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.,Howard Hughes Medical Institute, Bethesda, Maryland 21205
| | - Eileen M Shore
- Department of Orthopedic Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104.,Center for Research in FOP and Related Disorders, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104.,Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104
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Spatiotemporal distribution of proliferation, proapoptotic and antiapoptotic factors in the early human limb development. Acta Histochem 2016; 118:527-36. [PMID: 27282649 DOI: 10.1016/j.acthis.2016.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 05/19/2016] [Accepted: 05/24/2016] [Indexed: 12/28/2022]
Abstract
Involvement of proliferation and apoptosis in the human limb development was analyzed electronmicroscopically and immunohistochemically in histological sections of 8 human embryos, 4(th) -10(th) week old, using apoptotic (caspase-3, AIF, BAX), anti-apoptotic (Bcl-2) and proliferation (Ki-67) markers, and TUNEL method. The data were analyzed by Mann-Whitney test, Kruskal-Wallis and Dunn's post hoc test. Initially, developing human limbs consisted of mesenchymal core and surface ectoderm with apical ectodermal ridge (AER). During progression of development, strong proliferation activity gradually decreased in the mesenchyme (from 78% to 68%) and in the epithelium (from 62% to 42%), while in the differentiating finger cartilages proliferation was constantly low (26-7%). Apoptotic caspase-3 and AIF-positive cells characterized mesenchyme and AER at earliest stages, while during digit separation they appeared in interdigital mesenchyme as well. Strong Bcl-2 expression was observed in AER, subridge mesenchyme and phalanges, while BAX expression charaterized limb areas undergoing apoptosis. Ultrastructurally, proliferating cells showed mitotic figures, while apoptotic cells were characterized by nuclear fragmentation. Macrophages were observed around the apoptotic cells. We suggest that intense proliferation enables growth and elongation of human limb primordia, and differential growth of digits. Both caspase-3 and AIF-dependant pathways of cell death control the extent of AER and numer of cells in the subridge mesenchyme at earliest developmental stages, as well as process of digit separation at later stages of limb development. Spatio-temporal co-expresson of Bcl-2 and BAX indicates their role in suppression of apoptosis and selective stimulation of growth during human limb morphogenesis.
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Elmore SA, Dixon D, Hailey JR, Harada T, Herbert RA, Maronpot RR, Nolte T, Rehg JE, Rittinghausen S, Rosol TJ, Satoh H, Vidal JD, Willard-Mack CL, Creasy DM. Recommendations from the INHAND Apoptosis/Necrosis Working Group. Toxicol Pathol 2016; 44:173-88. [PMID: 26879688 DOI: 10.1177/0192623315625859] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Historically, there has been confusion relating to the diagnostic nomenclature for individual cell death. Toxicologic pathologists have generally used the terms "single cell necrosis" and "apoptosis" interchangeably. Increased research on the mechanisms of cell death in recent years has led to the understanding that apoptosis and necrosis involve different cellular pathways and that these differences can have important implications when considering overall mechanisms of toxicity, and, for these reasons, the separate terms of apoptosis and necrosis should be used whenever differentiation is possible. However, it is also recognized that differentiation of the precise pathway of cell death may not be important, necessary, or possible in routine toxicity studies and so a more general term to indicate cell death is warranted in these situations. Morphological distinction between these two forms of cell death can sometimes be straightforward but can also be challenging. This article provides a brief discussion of the cellular mechanisms and morphological features of apoptosis and necrosis as well as guidance on when the pathologist should use these terms. It provides recommended nomenclature along with diagnostic criteria (in hematoxylin and eosin [H&E]-stained sections) for the most common forms of cell death (apoptosis and necrosis). This document is intended to serve as current guidance for the nomenclature of cell death for the International Harmonization of Nomenclature and Diagnostic Criteria Organ Working Groups and the toxicologic pathology community at large. The specific recommendations are:Use necrosis and apoptosis as separate diagnostic terms.Use modifiers to denote the distribution of necrosis (e.g., necrosis, single cell; necrosis, focal; necrosis, diffuse; etc.).Use the combined term apoptosis/single cell necrosis whenThere is no requirement or need to split the processes, orWhen the nature of cell death cannot be determined with certainty, orWhen both processes are present together. The diagnosis should be based primarily on the morphological features in H&E-stained sections. When needed, additional, special techniques to identify and characterize apoptosis can also be used.
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Affiliation(s)
- Susan A Elmore
- Cellular and Molecular Pathology Branch, National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Darlene Dixon
- Molecular Pathogenesis Group, National Toxicology Program Laboratory, Division of the NTP, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - Takanori Harada
- The Institute of Environmental Toxicology, Joso-shi, Ibaraki, Japan
| | - Ronald A Herbert
- Cellular and Molecular Pathology Branch, National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - Thomas Nolte
- Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Jerold E Rehg
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Susanne Rittinghausen
- Fraunhofer Institute for Toxicology and Experimental Medicine ITEM, Hannover, Germany
| | - Thomas J Rosol
- Department of Veterinary Biosciences, Ohio State University, Columbus, Ohio, USA
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7
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Abstract
Apoptosis is a cellular suicide program, which is on the one hand used to remove superfluous cells thereby promoting tissue or organ morphogenesis. On the other hand, the programmed killing of cells is also critical when potentially harmful cells emerge in a developing or adult organism thereby endangering survival. Due to its critical role apoptosis is tightly controlled, however so far, its regulation on the transcriptional level is less studied and understood. Hox genes, a highly conserved gene family encoding homeodomain transcription factors, have crucial roles in development. One of their prominent functions is to shape animal body plans by eliciting different developmental programs along the anterior-posterior axis. To this end, Hox proteins transcriptionally regulate numerous processes in a coordinated manner, including cell-type specification, differentiation, motility, proliferation as well as apoptosis. In this review, we will focus on how Hox proteins control organismal morphology and function by regulating the apoptotic machinery. We will first focus on well-established paradigms of Hox-apoptosis interactions and summarize how Hox transcription factors control morphological outputs and differentially shape tissues along the anterior-posterior axis by fine-tuning apoptosis in a healthy organism. We will then discuss the consequences when this interaction is disturbed and will conclude with some ideas and concepts emerging from these studies.
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8
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Tower J. Programmed cell death in aging. Ageing Res Rev 2015; 23:90-100. [PMID: 25862945 DOI: 10.1016/j.arr.2015.04.002] [Citation(s) in RCA: 256] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 03/15/2015] [Accepted: 04/01/2015] [Indexed: 02/08/2023]
Abstract
Programmed cell death (PCD) pathways, including apoptosis and regulated necrosis, are required for normal cell turnover and tissue homeostasis. Mis-regulation of PCD is increasingly implicated in aging and aging-related disease. During aging the cell turnover rate declines for several highly-mitotic tissues. Aging-associated disruptions in systemic and inter-cell signaling combined with cell-autonomous damage and mitochondrial malfunction result in increased PCD in some cell types, and decreased PCD in other cell types. Increased PCD during aging is implicated in immune system decline, skeletal muscle wasting (sarcopenia), loss of cells in the heart, and neurodegenerative disease. In contrast, cancer cells and senescent cells are resistant to PCD, enabling them to increase in abundance during aging. PCD pathways limit life span in fungi, but whether PCD pathways normally limit adult metazoan life span is not yet clear. PCD is regulated by a balance of negative and positive factors, including the mitochondria, which are particularly subject to aging-associated malfunction.
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Restelli M, Molinari E, Marinari B, Conte D, Gnesutta N, Costanzo A, Merlo GR, Guerrini L. FGF8, c-Abl and p300 participate in a pathway that controls stability and function of the ΔNp63α protein. Hum Mol Genet 2015; 24:4185-97. [PMID: 25911675 PMCID: PMC4492388 DOI: 10.1093/hmg/ddv151] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/21/2015] [Indexed: 12/22/2022] Open
Abstract
The p63 transcription factor, homolog to the p53 tumor suppressor gene, plays a crucial role in epidermal and limb development, as its mutations are associated to human congenital syndromes characterized by skin, craniofacial and limb defects. While limb and skin-specific p63 transcriptional targets are being discovered, little is known of the post-translation modifications controlling ΔNp63α functions. Here we show that the p300 acetyl-transferase physically interacts in vivo with ΔNp63α and catalyzes its acetylation on lysine 193 (K193) inducing ΔNp63α stabilization and activating specific transcriptional functions. Furthermore we show that Fibroblast Growth Factor-8 (FGF8), a morphogenetic signaling molecule essential for embryonic limb development, increases the binding of ΔNp63α to the tyrosine kinase c-Abl as well as the levels of ΔNp63α acetylation. Notably, the natural mutant ΔNp63α-K193E, associated to the Split-Hand/Foot Malformation-IV syndrome, cannot be acetylated by this pathway. This mutant ΔNp63α protein displays promoter-specific loss of DNA binding activity and consequent altered expression of development-associated ΔNp63α target genes. Our results link FGF8, c-Abl and p300 in a regulatory pathway that controls ΔNp63α protein stability and transcriptional activity. Hence, limb malformation-causing p63 mutations, such as the K193E mutation, are likely to result in aberrant limb development via the combined action of altered protein stability and altered promoter occupancy.
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Affiliation(s)
- Michela Restelli
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Elisa Molinari
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Barbara Marinari
- Dermatology Unit, NESMOS Department, Università di Roma La Sapienza, I-00189 Rome, Italy and
| | - Daniele Conte
- Department of Molecular Biotechnologies and Health Sciences, Università di Torino, I-10126 Torino, Italy
| | - Nerina Gnesutta
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy
| | - Antonio Costanzo
- Dermatology Unit, NESMOS Department, Università di Roma La Sapienza, I-00189 Rome, Italy and
| | - Giorgio Roberto Merlo
- Department of Molecular Biotechnologies and Health Sciences, Università di Torino, I-10126 Torino, Italy
| | - Luisa Guerrini
- Department of Biosciences, Università degli Studi di Milano, 20133 Milano, Italy,
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Mason MK, Hockman D, Curry L, Cunningham TJ, Duester G, Logan M, Jacobs DS, Illing N. Retinoic acid-independent expression of Meis2 during autopod patterning in the developing bat and mouse limb. EvoDevo 2015; 6:6. [PMID: 25861444 PMCID: PMC4389300 DOI: 10.1186/s13227-015-0001-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Accepted: 02/04/2015] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND The bat has strikingly divergent forelimbs (long digits supporting wing membranes) and hindlimbs (short, typically free digits) due to the distinct requirements of both aerial and terrestrial locomotion. During embryonic development, the morphology of the bat forelimb deviates dramatically from the mouse and chick, offering an alternative paradigm for identifying genes that play an important role in limb patterning. RESULTS Using transcriptome analysis of developing Natal long-fingered bat (Miniopterus natalensis) fore- and hindlimbs, we demonstrate that the transcription factor Meis2 has a significantly higher expression in bat forelimb autopods compared to hindlimbs. Validation by reverse transcriptase and quantitative polymerase chain reaction (RT-qPCR) and whole mount in situ hybridisation shows that Meis2, conventionally known as a marker of the early proximal limb bud, is upregulated in the bat forelimb autopod from CS16. Meis2 expression is localised to the expanding interdigital webbing and the membranes linking the wing to the hindlimb and tail. In mice, Meis2 is also expressed in the interdigital region prior to tissue regression. This interdigital Meis2 expression is not activated by retinoic acid (RA) signalling as it is present in the retained interdigital tissue of Rdh10 (trex/trex) mice, which lack RA. Additionally, genes encoding RA-synthesising enzymes, Rdh10 and Aldh1a2, and the RA nuclear receptor Rarβ are robustly expressed in bat fore- and hindlimb interdigital tissues indicating that the mechanism that retains interdigital tissue in bats also occurs independently of RA signalling. CONCLUSIONS Mammalian interdigital Meis2 expression, and upregulation in the interdigital webbing of bat wings, suggests an important role for Meis2 in autopod development. Interdigital Meis2 expression is RA-independent, and retention of interdigital webbing in bat wings is not due to the suppression of RA-induced cell death. Rather, RA signalling may play a role in the thinning (rather than complete loss) of the interdigital tissue in the bat forelimb, while Meis2 may interact with other factors during both bat and mouse autopod development to maintain a pool of interdigital cells that contribute to digit patterning and growth.
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Affiliation(s)
- Mandy K Mason
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701 South Africa
| | - Dorit Hockman
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701 South Africa ; Present address: Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS UK
| | - Lyle Curry
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701 South Africa
| | - Thomas J Cunningham
- Sanford-Burnham Medical Research Institute, Development, Aging, and Regeneration Program, La Jolla, 92037 California USA
| | - Gregg Duester
- Sanford-Burnham Medical Research Institute, Development, Aging, and Regeneration Program, La Jolla, 92037 California USA
| | - Malcolm Logan
- Randall Division, King's College London, London, SE1 1UL UK
| | - David S Jacobs
- Department of Biological Sciences, University of Cape Town, Rondebosch, 7701 South Africa
| | - Nicola Illing
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7701 South Africa
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11
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Molecular Control of Interdigital Cell Death and Cell Differentiation by Retinoic Acid during Digit Development. J Dev Biol 2014. [DOI: 10.3390/jdb2020138] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Kim HS, Montana V, Jang HJ, Parpura V, Kim JA. Epigallocatechin gallate (EGCG) stimulates autophagy in vascular endothelial cells: a potential role for reducing lipid accumulation. J Biol Chem 2013; 288:22693-705. [PMID: 23754277 PMCID: PMC3829354 DOI: 10.1074/jbc.m113.477505] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/28/2013] [Indexed: 12/17/2022] Open
Abstract
Epigallocatechin gallate (EGCG) is a major polyphenol in green tea that has beneficial effects in the prevention of cardiovascular disease. Autophagy is a cellular process that protects cells from stressful conditions. To determine whether the beneficial effect of EGCG is mediated by a mechanism involving autophagy, the roles of the EGCG-stimulated autophagy in the context of ectopic lipid accumulation were investigated. Treatment with EGCG increased formation of LC3-II and autophagosomes in primary bovine aortic endothelial cells (BAEC). Activation of calmodulin-dependent protein kinase kinase β was required for EGCG-induced LC3-II formation, as evidenced by the fact that EGCG-induced LC3-II formation was significantly impaired by knockdown of calmodulin-dependent protein kinase kinase β. This effect is most likely due to cytosolic Ca(2+) load. To determine whether EGCG affects palmitate-induced lipid accumulation, the effects of EGCG on autophagic flux and co-localization of lipid droplets and autophagolysosomes were examined. EGCG normalized the palmitate-induced impairment of autophagic flux. Accumulation of lipid droplets by palmitate was markedly reduced by EGCG. Blocking autophagosomal degradation opposed the effect of EGCG in ectopic lipid accumulation, suggesting the action of EGCG is through autophagosomal degradation. The mechanism for this could be due to the increased co-localization of lipid droplets and autophagolysosomes. Co-localization of lipid droplets with LC3 and lysosome was dramatically increased when the cells were treated with EGCG and palmitate compared with the cells treated with palmitate alone. Collectively, these findings suggest that EGCG regulates ectopic lipid accumulation through a facilitated autophagic flux and further imply that EGCG may be a potential therapeutic reagent to prevent cardiovascular complications.
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Affiliation(s)
- Hae-Suk Kim
- From the Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, and
| | - Vedrana Montana
- Neurobiology, Center for Glial Biology in Medicine, Atomic Force Microscopy and Nanotechnology Laboratories, Civitan International Research Center, Evelyn F. McKnight Brain Institute, and
| | - Hyun-Ju Jang
- From the Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, and
| | - Vladimir Parpura
- Neurobiology, Center for Glial Biology in Medicine, Atomic Force Microscopy and Nanotechnology Laboratories, Civitan International Research Center, Evelyn F. McKnight Brain Institute, and
- the Department of Biotechnology, University of Rijeka, 51000 Rijeka, Croatia
| | - Jeong-a Kim
- From the Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, and
- Departments of Molecular Cellular Pathology and
- Comprehensive Diabetes Center, University of Alabama at Birmingham, Birmingham, Alabama 35294 and
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13
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Díaz-Hernández ME, Bustamante M, Galván-Hernández CI, Chimal-Monroy J. Irx1 and Irx2 are coordinately expressed and regulated by retinoic acid, TGFβ and FGF signaling during chick hindlimb development. PLoS One 2013; 8:e58549. [PMID: 23505533 PMCID: PMC3594311 DOI: 10.1371/journal.pone.0058549] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 02/07/2013] [Indexed: 01/17/2023] Open
Abstract
The Iroquois homeobox (Irx) genes play a crucial role in the regionalization and patterning of tissues and organs during metazoan development. The Irx1 and Irx2 gene expression pattern during hindlimb development has been investigated in different species, but its regulation during hindlimb morphogenesis has not been explored yet. The aim of this study was to evaluate the gene expression pattern of Irx1 and Irx2 as well as their regulation by important regulators of hindlimb development such as retinoic acid (RA), transforming growth factor β (TGFβ) and fibroblast growth factor (FGF) signaling during chick hindlimb development. Irx1 and Irx2 were coordinately expressed in the interdigital tissue, digital primordia, joints and in the boundary between cartilage and non-cartilage tissue. Down-regulation of Irx1 and Irx2 expression at the interdigital tissue coincided with the onset of cell death. RA was found to down-regulate their expression by a bone morphogenetic protein-independent mechanism before any evidence of cell death. Furthermore, TGFβ protein regulated Irx1 and Irx2 in a stage-dependent manner at the interdigital tissue, it inhibited their expression when it was administered to the interdigital tissue at developing stages before their normal down-regulation. TGFβ administered to the interdigital tissue at developing stages after normal down-regulation of Irx1 and Irx2 evidenced that expression of these genes marked the boundary between cartilage tissue and non-cartilage tissue. It was also found that at early stages of hindlimb development FGF signaling inhibited the expression of Irx2. In conclusion, the present study demonstrates that Irx1 and Irx2 are coordinately expressed and regulated during chick embryo hindlimb development as occurs in other species of vertebrates supporting the notion that the genomic architecture of Irx clusters is conserved in vertebrates.
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Affiliation(s)
- Martha Elena Díaz-Hernández
- Departamento de Medicina Genómica y Toxicología Ambiental, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México. México, Distrito Federal, México
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