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Sachslehner AP, Surbek M, Holthaus KB, Steinbinder J, Golabi B, Hess C, Eckhart L. The Evolution of Transglutaminases Underlies the Origin and Loss of Cornified Skin Appendages in Vertebrates. Mol Biol Evol 2024; 41:msae100. [PMID: 38781495 DOI: 10.1093/molbev/msae100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 04/11/2024] [Accepted: 05/20/2024] [Indexed: 05/25/2024] Open
Abstract
Transglutaminases (TGMs) cross-link proteins by introducing covalent bonds between glutamine and lysine residues. These cross-links are essential for epithelial cornification which enables tetrapods to live on land. Here, we investigated which evolutionary adaptations of vertebrates were associated with specific changes in the family of TGM genes. We determined the catalog of TGMs in the main clades of vertebrates, performed a comprehensive phylogenetic analysis of TGMs, and localized the distribution of selected TGMs in tissues. Our data suggest that TGM1 is the phylogenetically oldest epithelial TGM, with orthologs being expressed in the cornified teeth of the lamprey, a basal vertebrate. Gene duplications led to the origin of TGM10 in stem vertebrates, the origin of TGM2 in jawed vertebrates, and an increasing number of epithelium-associated TGM genes in the lineage leading to terrestrial vertebrates. TGM9 is expressed in the epithelial egg tooth, and its evolutionary origin in stem amniotes coincided with the evolution of embryonic development in eggs that are surrounded by a protective shell. Conversely, viviparous mammals have lost both the epithelial egg tooth and TGM9. TGM3 and TGM6 evolved as regulators of cornification in hair follicles and underwent pseudogenization upon the evolutionary loss of hair in cetaceans. Taken together, this study reveals the gain and loss of vertebrate TGM genes in association with the evolution of cornified skin appendages and suggests an important role of TGM9 in the evolution of amniotes.
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Affiliation(s)
| | - Marta Surbek
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
| | | | - Julia Steinbinder
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
| | - Bahar Golabi
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
| | - Claudia Hess
- Clinic for Poultry and Fish Medicine, Department for Farm Animals and Veterinary Public Health, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Leopold Eckhart
- Department of Dermatology, Medical University of Vienna, 1090 Vienna, Austria
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2
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Tagoe H, Hassan S, Bliss E, Youssef G, Heywood W, Mills K, Harper JI, O'Shaughnessy RFL. Chronic activation of Toll-like receptor 2 induces an ichthyotic skin phenotype. Br J Dermatol 2023; 189:91-102. [PMID: 36972303 DOI: 10.1093/bjd/ljad095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 03/06/2023] [Accepted: 03/18/2023] [Indexed: 03/29/2023]
Abstract
BACKGROUND Ichthyosis defines a group of chronic conditions that manifest phenotypically as a thick layer of scales, often affecting the entire skin. While the gene mutations that lead to ichthyosis are well documented, the actual signalling mechanisms that lead to scaling are poorly characterized; however, recent publications suggest that common mechanisms are active in ichthyotic tissue and in analogous models of ichthyosis. OBJECTIVES To determine common mechanisms of hyperkeratosis that may be easily targeted with small-molecule inhibitors. METHODS We combined gene expression analysis of gene-specific short hairpin RNA (shRNA) knockdowns in rat epidermal keratinocytes (REKs) of two genes mutated in autosomal recessive congenital ichthyosis (ARCI), Tgm1 and Alox12b, and proteomic analysis of skin scale from patients with ARCI, as well as RNA sequencing data from rat epidermal keratinocytes treated with the Toll-like receptor 2 (TLR2) agonist Pam3CSK4. RESULTS We identified common activation of the TLR2 pathway. Exogenous TLR2 activation led to increased expression of important cornified envelope genes and, in organotypic culture, caused hyperkeratosis. Conversely, blockade of TLR2 signalling in keratinocytes from patients with ichthyosis and our shRNA models reduced the expression of keratin 1, a structural protein overexpressed in ichthyosis scale. A time course of TLR2 activation in REKs revealed that although there was rapid initial activation of innate immune pathways, this was rapidly superseded by widespread upregulation of epidermal differentiation-related proteins. Both nuclear factor kappa B phosphorylation and GATA3 upregulation was associated with this switch, and GATA3 overexpression was sufficient to increase keratin 1 expression. CONCLUSIONS Taken together, these data define a dual role for TLR2 activation during epidermal barrier repair that may be a useful therapeutic modality in treating diseases of epidermal barrier dysfunction.
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Affiliation(s)
- Hephzi Tagoe
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | - Sakinah Hassan
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | | | - Gehad Youssef
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
- Livingstone Skin Research Centre
| | | | | | - John I Harper
- Livingstone Skin Research Centre
- Department of Immunobiology and Dermatology, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Ryan F L O'Shaughnessy
- Centre for Cell Biology and Cutaneous Research, Queen Mary University of London, London, UK
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3
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Gutiérrez-Cerrajero C, Sprecher E, Paller AS, Akiyama M, Mazereeuw-Hautier J, Hernández-Martín A, González-Sarmiento R. Ichthyosis. Nat Rev Dis Primers 2023; 9:2. [PMID: 36658199 DOI: 10.1038/s41572-022-00412-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/02/2022] [Indexed: 01/20/2023]
Abstract
The ichthyoses are a large, heterogeneous group of skin cornification disorders. They can be inherited or acquired, and result in defective keratinocyte differentiation and abnormal epidermal barrier formation. The resultant skin barrier dysfunction leads to increased transepidermal water loss and inflammation. Disordered cornification is clinically characterized by skin scaling with various degrees of thickening, desquamation (peeling) and erythema (redness). Regardless of the type of ichthyosis, many patients suffer from itching, recurrent infections, sweating impairment (hypohidrosis) with heat intolerance, and diverse ocular, hearing and nutritional complications that should be monitored periodically. The characteristic clinical features are considered to be a homeostatic attempt to repair the skin barrier, but heterogeneous clinical presentation and imperfect phenotype-genotype correlation hinder diagnosis. An accurate molecular diagnosis is, however, crucial for predicting prognosis and providing appropriate genetic counselling. Most ichthyoses severely affect patient quality of life and, in severe forms, may cause considerable disability and even death. So far, treatment provides only symptomatic relief. It is lifelong, expensive, time-consuming, and often provides disappointing results. A better understanding of the molecular mechanisms that underlie these conditions is essential for designing pathogenesis-driven and patient-tailored innovative therapeutic solutions.
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Affiliation(s)
- Carlos Gutiérrez-Cerrajero
- Department of Medicine, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,Biomedical Research Institute of Salamanca (IBSAL), Salamanca, Spain
| | - Eli Sprecher
- Division of Dermatology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amy S Paller
- Departments of Dermatology and Paediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Masashi Akiyama
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | | | | | - Rogelio González-Sarmiento
- Department of Medicine, Faculty of Medicine, University of Salamanca, Salamanca, Spain.,Biomedical Research Institute of Salamanca (IBSAL), Salamanca, Spain
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4
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Murata T, Honda T, Mostafa A, Kabashima K. Stratum corneum as polymer sheet: concept and cornification processes. Trends Mol Med 2022; 28:350-359. [PMID: 35337733 DOI: 10.1016/j.molmed.2022.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/20/2022] [Accepted: 02/22/2022] [Indexed: 12/12/2022]
Abstract
The skin barrier protects our body from external insults and water loss through a specialized layer, the stratum corneum. The stratum corneum, an accumulation of dead keratinocytes (corneocytes), comprises lipids and supporting cell bodies. We propose a framework of lipid-filled polymer sheet of corneocytes, a unique structure that achieves flexibility and robustness, updating the rigid image of the historical bricks-and-mortar model. The polymerization of polymer sheet (cornification) by cell death of keratinocytes (corneoptosis) is delicately and dynamically controlled by cytoplasmic calcium ion and pH. Understanding the structure and formation of the stratum corneum can lead to better treatments for skin diseases and a better understanding of the evolution of the stratum corneum.
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Affiliation(s)
- Teruasa Murata
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| | - Tetsuya Honda
- Department of Dermatology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Alshimaa Mostafa
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kenji Kabashima
- Department of Dermatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan; Singapore Immunology Network (SIgN) and Skin Research Institute of Singapore (SRIS), Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore
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5
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Chulpanova DS, Shaimardanova AA, Ponomarev AS, Elsheikh S, Rizvanov AA, Solovyeva VV. Current Strategies for the Gene Therapy of Autosomal Recessive Congenital Ichthyosis and Other Types of Inherited Ichthyosis. Int J Mol Sci 2022; 23:2506. [PMID: 35269649 PMCID: PMC8910354 DOI: 10.3390/ijms23052506] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 01/27/2023] Open
Abstract
Mutations in genes such as transglutaminase-1 (TGM1), which are responsible for the formation and normal functioning of a lipid barrier, lead to the development of autosomal recessive congenital ichthyosis (ARCI). ARCIs are characterized by varying degrees of hyperkeratosis and the presence of scales on the body surface since birth. The quality of life of patients is often significantly affected, and in order to alleviate the manifestations of the disease, symptomatic therapy with moisturizers, keratolytics, retinoids and other cosmetic substances is often used to improve the condition of the patients' skin. Graft transplantation is commonly used to correct defects of the eye. However, these approaches offer symptomatic treatment that does not restore the lost protein function or provide a long-term skin barrier. Gene and cell therapies are evolving as promising therapy for ARCIs that can correct the functional activity of altered proteins. However, these approaches are still at an early stage of development. This review discusses current studies of gene and cell therapy approaches for various types of ichthyosis and their further prospects for patient treatment.
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Affiliation(s)
- Daria S. Chulpanova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (D.S.C.); (A.A.S.); (A.S.P.); (A.A.R.)
| | - Alisa A. Shaimardanova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (D.S.C.); (A.A.S.); (A.S.P.); (A.A.R.)
| | - Aleksei S. Ponomarev
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (D.S.C.); (A.A.S.); (A.S.P.); (A.A.R.)
| | - Somaia Elsheikh
- Division of Cancer and Stem Cell, University of Nottingham, Nottingham LE12 5RD, UK;
| | - Albert A. Rizvanov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (D.S.C.); (A.A.S.); (A.S.P.); (A.A.R.)
| | - Valeriya V. Solovyeva
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia; (D.S.C.); (A.A.S.); (A.S.P.); (A.A.R.)
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6
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Yamanishi K, Imai Y. Alarmins/stressorins and immune dysregulation in intractable skin disorders. Allergol Int 2021; 70:421-429. [PMID: 34127380 DOI: 10.1016/j.alit.2021.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 04/21/2021] [Indexed: 12/18/2022] Open
Abstract
Unlike other barrier epithelia of internal organs, the stratified squamous epithelium of the skin is always exposed to the external environment. However, the robust barrier structure and function of the skin are highly resistant against external insults so as to not easily allow foreign invasions. Upon sensing danger signals, the innate immunity system is promptly activated. This process is mediated by alarmins, which are released passively from damaged cells. Nuclear alarmins or stressorins are actively released from intact cells in response to various cellular stresses. Alarmins/stressorins are deeply involved in the disease processes of chronic skin disorders of an unknown cause, such as rosacea, psoriasis, and atopic dermatitis. Furthermore, alarmins/stressorins are also induced in the congenital skin disorders of ichthyosis and keratoderma due to defective keratinization. Studies on alarmin activation and its downstream pathways may help develop novel therapeutic agents for intractable skin disorders.
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7
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Identification of Chicken Transglutaminase 1 and In Situ Localization of Transglutaminase Activity in Avian Skin and Esophagus. Genes (Basel) 2021; 12:genes12101565. [PMID: 34680960 PMCID: PMC8535770 DOI: 10.3390/genes12101565] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 12/30/2022] Open
Abstract
Transglutaminase 1 (TGM1) is a membrane-anchored enzyme that cross-links proteins during terminal differentiation of epidermal and esophageal keratinocytes in mammals. The current genome assembly of the chicken, which is a major model for avian skin biology, does not include an annotated region corresponding to TGM1. To close this gap of knowledge about the genetic control of avian cornification, we analyzed RNA-sequencing reads from organotypic chicken skin and identified TGM1 mRNA. By RT-PCR, we demonstrated that TGM1 is expressed in the skin and esophagus of chickens. The cysteine-rich sequence motif required for palmitoylation and membrane anchorage is conserved in the chicken TGM1 protein, and differentiated chicken keratinocytes display membrane-associated transglutaminase activity. Expression of TGM1 and prominent transglutaminase activity in the esophageal epithelium was also demonstrated in the zebra finch. Altogether, the results of this study indicate that TGM1 is conserved among birds and suggest that chicken keratinocytes may be a useful model for the study of TGM1 in non-mammalian cornification.
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8
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Sassa T, Imai Y, Kihara A, Yamanishi K. Protein-bound ceramide levels in the epidermis of transglutaminase 1-deficient mice. J Dermatol 2021; 48:1799-1801. [PMID: 34405428 DOI: 10.1111/1346-8138.16113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/27/2021] [Accepted: 07/31/2021] [Indexed: 11/30/2022]
Affiliation(s)
- Takayuki Sassa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Yasutomo Imai
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - Kiyofumi Yamanishi
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Japan
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9
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Deng Z, Cangkrama M, Butt T, Jane SM, Carpinelli MR. Grainyhead-like transcription factors: guardians of the skin barrier. Vet Dermatol 2021; 32:553-e152. [PMID: 33843098 DOI: 10.1111/vde.12956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/24/2020] [Accepted: 12/14/2020] [Indexed: 01/02/2023]
Abstract
There has been selective pressure to maintain a skin barrier since terrestrial animals evolved 360 million years ago. These animals acquired an unique integumentary system with a keratinized, stratified, squamous epithelium surface barrier. The barrier protects against dehydration and entry of microbes and toxins. The skin barrier centres on the stratum corneum layer of the epidermis and consists of cornified envelopes cemented by the intercorneocyte lipid matrix. Multiple components of the barrier undergo cross-linking by transglutaminase (TGM) enzymes, while keratins provide additional mechanical strength. Cellular tight junctions also are crucial for barrier integrity. The grainyhead-like (GRHL) transcription factors regulate the formation and maintenance of the integument in diverse species. GRHL3 is essential for formation of the skin barrier during embryonic development, whereas GRHL1 maintains the skin barrier postnatally. This is achieved by transactivation of Tgm1 and Tgm5, respectively. In addition to its barrier function, GRHL3 plays key roles in wound repair and as an epidermal tumour suppressor. In its former role, GRHL3 activates the planar cell polarity signalling pathway to mediate wound healing by providing directional migration cues. In squamous epithelium, GRHL3 regulates the balance between proliferation and differentiation, and its loss induces squamous cell carcinoma (SCC). In the skin, this is mediated through increased expression of MIR21, which reduces the expression levels of GRHL3 and its direct target, PTEN, leading to activation of the PI3K-AKT signalling pathway. These data position the GRHL family as master regulators of epidermal homeostasis across a vast gulf of evolutionary history.
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Affiliation(s)
- Zihao Deng
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Michael Cangkrama
- Department of Biology, Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland
| | - Tariq Butt
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Stephen M Jane
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
| | - Marina R Carpinelli
- Department of Medicine, Central Clinical School, Monash University, Melbourne, Australia
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10
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Novel Homozygous Mutations in the Genes TGM1, SULT2B1, SPINK5 and FLG in Four Families Underlying Congenital Ichthyosis. Genes (Basel) 2021; 12:genes12030373. [PMID: 33807935 PMCID: PMC7999895 DOI: 10.3390/genes12030373] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 02/07/2023] Open
Abstract
Background: Ichthyoses are a large group of hereditary cornification disorders, which are both clinically and etiologically heterogeneous and affect mostly all the skin surface of the patients. Ichthyosis has its origin in an ancient Greek word “ichthys” meaning fish, this is because the ichthyosis patients have dry, thickened, and scaly skin. There is an excess accumulation of epidermal cells resulting in the appearance of continuous and widespread scales on the body. There are many varieties of ichthyosis with a broad spectrum of intensity, severity, and associated symptoms, most of them are extremely rare. Ichthyosis vulgaris is the most frequently occurring type of ichthyoses. Method: The present study consists of four Pakistani ichthyosis families (A, B, C, and D). Whole exome sequencing (WES) approach was used to identify the pathogenic sequence variants in probands. The segregation of these variants in other participants was confirmed by Sanger sequencing. Results: Total four variants including, two splice site (TGM1: c.2088 + 1G > A) and (SPINK5: c.882 + 1G > T), a missense (SULT2B1: c.419C > T; p. Ala140Val), and a nonsense (FLG: c.6109C > T; p. Arg2037Ter) variant were identified in families A, C, B, and D, respectively, as causative mutations responsible for ichthyosis in these families. Conclusion: Our study unravels the molecular etiology of the four Pakistani ichthyosis families and validates the involvement of TGM1, SULT2B1, SPINK5, and FLG, in the etiology of different forms of ichthyosis. In addition, this study also aims to give a detailed clinical report of the studied ichthyosis families.
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11
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Transglutaminase 2 as a Marker for Inflammation and Therapeutic Target in Sepsis. Int J Mol Sci 2021; 22:ijms22041897. [PMID: 33672962 PMCID: PMC7918628 DOI: 10.3390/ijms22041897] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/08/2021] [Accepted: 02/11/2021] [Indexed: 02/07/2023] Open
Abstract
Sepsis results in lethal organ malfunction due to dysregulated host response to infection, which is a condition with increasing prevalence worldwide. Transglutaminase 2 (TG2) is a crosslinking enzyme that forms a covalent bond between lysine and glutamine. TG2 plays important roles in diverse cellular processes, including extracellular matrix stabilization, cytoskeletal function, cell motility, adhesion, signal transduction, apoptosis, and cell survival. We have shown that the co-culture of Candida albicans and hepatocytes activates and induces the translocation of TG2 into the nucleus. In addition, the expression and activation of TG2 in liver macrophages was dramatically induced in the lipopolysaccharide-injected and cecal ligation puncture-operated mouse models of sepsis. Based on these findings and recently published research, we have reviewed the current understanding of the relationship between TG2 and sepsis. Following the genetic and pharmacological inhibition of TG2, we also assessed the evidence regarding the use of TG2 as a potential marker and therapeutic target in inflammation and sepsis.
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12
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Ishitsuka Y, Roop DR, Ogawa T. "Structural imprinting" of the cutaneous immune effector function. Tissue Barriers 2021; 9:1851561. [PMID: 33270506 PMCID: PMC7849724 DOI: 10.1080/21688370.2020.1851561] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/07/2020] [Accepted: 11/10/2020] [Indexed: 01/30/2023] Open
Abstract
Keratinization provides tolerance to desiccation and mechanical durability. Loricrin, which is an epidermal thiol-rich protein, efficiently stabilizes terminally differentiated keratinocytes and maintains redox homeostasis. The discovery of the largely asymptomatic loricrin knockout (LKO) phenotype decades ago was rather unpredicted. Nevertheless, when including redox-driven, NF-E2-related factor 2-mediated backup responses, LKO mice provide opportunities for the observation of altered or "quasi-normal" homeostasis. Specifically, given that the tissue structure, as well as the local metabolism, transmits immunological signals, we sought to dissect the consequence of truncated epidermal differentiation program from immunological perspectives. Through a review of the aggregated evidence, we have attempted to generate an integrated view of the regulation of the peripheral immune system, which possibly occurs within the squamous epithelial tissue with truncated differentiation. This synthesis might not only provide insights into keratinization but also lead to the identification of factors intrinsic to the epidermis that imprint the immune effector function.
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Affiliation(s)
- Yosuke Ishitsuka
- Department of Dermatology, Osaka University Graduate School of Medicine, Osaka, Japan
- Department of Dermatology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Dennis R. Roop
- Department of Dermatology and Charles C. Gates Center for Regenerative Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
| | - Tatsuya Ogawa
- Department of Dermatology, Osaka University Graduate School of Medicine, Osaka, Japan
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13
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Chermnykh ES, Alpeeva EV, Vorotelyak EA. Transglutaminase 3: The Involvement in Epithelial Differentiation and Cancer. Cells 2020; 9:cells9091996. [PMID: 32872587 PMCID: PMC7563467 DOI: 10.3390/cells9091996] [Citation(s) in RCA: 20] [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: 06/01/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 12/14/2022] Open
Abstract
Transglutaminases (TGMs) contribute to the formation of rigid, insoluble macromolecular complexes, which are essential for the epidermis and hair follicles to perform protective and barrier functions against the environment. During differentiation, epidermal keratinocytes undergo structural alterations being transformed into cornified cells, which constitute a highly tough outermost layer of the epidermis, the stratum corneum. Similar processes occur during the hardening of the hair follicle and the hair shaft, which is provided by the enzymatic cross-linking of the structural proteins and keratin intermediate filaments. TGM3, also known as epidermal TGM, is one of the pivotal enzymes responsible for the formation of protein polymers in the epidermis and the hair follicle. Numerous studies have shown that TGM3 is extensively involved in epidermal and hair follicle physiology and pathology. However, the roles of TGM3, its substrates, and its importance for the integument system are not fully understood. Here, we summarize the main advances that have recently been achieved in TGM3 analyses in skin and hair follicle biology and also in understanding the functional role of TGM3 in human tumor pathology as well as the reliability of its prognostic clinical usage as a cancer diagnosis biomarker. This review also focuses on human and murine hair follicle abnormalities connected with TGM3 mutations.
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14
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Ishitsuka Y, Ogawa T, Roop D. The KEAP1/NRF2 Signaling Pathway in Keratinization. Antioxidants (Basel) 2020; 9:E751. [PMID: 32823937 PMCID: PMC7465315 DOI: 10.3390/antiox9080751] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/09/2020] [Accepted: 08/10/2020] [Indexed: 12/18/2022] Open
Abstract
Keratinization is a tissue adaptation, but aberrant keratinization is associated with skin disorders such as ichthyoses, atopic dermatitis, psoriasis, and acne. The disease phenotype stems from the interaction between genes and the environment; therefore, an understanding of the adaptation machinery may lead to a new appreciation of pathomechanisms. The KEAP1/NRF2 signaling pathway mediates the environmental responses of squamous epithelial tissue. The unpredicted outcome of the Keap1-null mutation in mice allowed us to revisit the basic principle of the biological process of keratinization: sulfur metabolism establishes unparalleled cytoprotection in the body wall of terrestrial mammals. We summarize the recent understanding of the KEAP1/NRF2 signaling pathway, which is a thiol-based sensor-effector apparatus, with particular focuses on epidermal differentiation in the context of the gene-environment interaction, the structure/function principles involved in KEAP1/NRF2 signaling, lessons from mouse models, and their pathological implications. This synthesis may provide insights into keratinization, which provides physical insulation and constitutes an essential innate integumentary defense system.
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Affiliation(s)
- Yosuke Ishitsuka
- Department of Dermatology, Faculty of Medicine, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan;
| | - Tatsuya Ogawa
- Department of Dermatology, Faculty of Medicine, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan;
| | - Dennis Roop
- Department of Dermatology and Charles C. Gates Center for Regenerative Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
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15
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Abstract
The terminal differentiation of the epidermis is a complex physiological process. During the past few decades, medical genetics has shown that defects in the stratum corneum (SC) permeability barrier cause a myriad of pathological conditions, ranging from common dry skin to lethal ichthyoses. Contrarily, molecular phylogenetics has revealed that amniotes have acquired a specialized form of cytoprotection cornification that provides mechanical resilience to the SC. This superior biochemical property, along with desiccation tolerance, is attributable to the proper formation of the macromolecular protein-lipid complex termed cornified cell envelopes (CE). Cornification largely depends on the peculiar biochemical and biophysical properties of loricrin, which is a major CE component. Despite its quantitative significance, loricrin knockout (LKO) mice have revealed it to be dispensable for the SC permeability barrier. Nevertheless, LKO mice have brought us valuable lessons. It is also becoming evident that absent loricrin affects skin homeostasis more profoundly in many more aspects than previously expected. Through an extensive review of aggregate evidence, we discuss herein the functional significance of the thiol-rich protein loricrin from a biochemical, genetic, pathological, metabolic, or immunological aspect with some theoretical and speculative perspectives.
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Affiliation(s)
- Yosuke Ishitsuka
- Department of Dermatology, Faculty of Medicine, University of Tsukuba 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan
| | - Dennis R. Roop
- Department of Dermatology and Charles C. Gates Center for Regenerative Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
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Chiba T, Nakahara T, Kohda F, Ichiki T, Manabe M, Furue M. Measurement of trihydroxy-linoleic acids in stratum corneum by tape-stripping: Possible biomarker of barrier function in atopic dermatitis. PLoS One 2019; 14:e0210013. [PMID: 30608955 PMCID: PMC6319710 DOI: 10.1371/journal.pone.0210013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/14/2018] [Indexed: 12/19/2022] Open
Abstract
Epidermal ceramides are indispensable lipids that maintain the functions of the stratum corneum. Esterified omega-hydroxyacyl-sphingosine (EOS) ceramide with a linoleate moiety is one of the most important ceramide species for forming cornified lipid envelopes. This linoleate moiety is eventually metabolized to trihydroxy-linoleic acid (triol, 9,10,13-trihydroxy-11E-octadecenoic acid). Thus, we assumed that a decrease of triols might reflect skin barrier dysfunction. Against this background, the purposes of this study were to measure the triols by a simple tape-stripping method and to determine the correlation between the amount of triols and transepidermal water loss (TEWL) as an indicator of barrier dysfunction in atopic dermatitis patients. Twenty Japanese subjects with normal skin and 20 atopic dermatitis patients were enrolled in this study. TEWL was measured and triols of the stratum corneum were analyzed by tape-stripping. The results showed for the first time that triols in the stratum corneum could be simply measured using the tape-stripping method. The triol levels in atopic dermatitis patients were much higher than those in healthy subjects. Moreover, the triol levels correlated with TEWL of non-lesional forearm skin in patients with atopic dermatitis. The results suggest that the assaying of triol levels via non-invasive tape-stripping could be beneficial for monitoring barrier function in atopic dermatitis.
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Affiliation(s)
- Takahito Chiba
- Department of Dermatology and Plastic Surgery, Akita University Graduate School of Medicine, Akita, Japan
- * E-mail:
| | - Takeshi Nakahara
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Futoshi Kohda
- Department of Dermatology, Aso Iizuka Hospital, Fukuoka, Japan
| | - Toshio Ichiki
- Department of Dermatology, Aso Iizuka Hospital, Fukuoka, Japan
| | - Motomu Manabe
- Department of Dermatology and Plastic Surgery, Akita University Graduate School of Medicine, Akita, Japan
| | - Masutaka Furue
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Zhang H, Ericsson M, Weström S, Vahlquist A, Virtanen M, Törmä H. Patients with congenital ichthyosis and TGM1 mutations overexpress other ARCI genes in the skin: Part of a barrier repair response? Exp Dermatol 2018; 28:1164-1171. [PMID: 30372788 PMCID: PMC7379499 DOI: 10.1111/exd.13813] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 10/16/2018] [Accepted: 10/22/2018] [Indexed: 12/14/2022]
Abstract
Autosomal recessive congenital ichthyosis (ARCI) is a group of monogenic skin disorders caused by mutations in any of at least 12 different genes, many of which are involved in the epidermal synthesis of ω-O-acylceramides (acylCer). AcylCer are essential precursors of the corneocyte lipid envelope crosslinked by transglutaminase-1 (TGm-1), or a yet unidentified enzyme, for normal skin barrier formation. We hypothesized that inactivating TGM1 mutations will lead to a compensatory overexpression of the transcripts involved in skin barrier repair, including many other ARCI-causing genes. Using microarray, we examined the global mRNA expression profile in skin biopsies from five ARCI patients with TGM1 mutations and four healthy controls. There were a total of 599 significantly differentially expressed genes (adjusted P < 0.05), out of which 272 showed more than 1.5 log2fold-change (FC) up- or down-regulation. Functional classification of the latter group of transcripts showed enrichment of mRNA encoding proteins mainly associated with biological pathways involved in keratinocyte differentiation and immune response. Moreover, the expression of seven out of twelve ARCI-causing genes was significantly increased (FC = 0.98-2.05). Also, many of the genes involved in keratinocyte differentiation (cornified envelope formation) and immune response (antimicrobial peptides and proinflammatory cytokines) were upregulated. The results from the microarray analysis were also verified for selected genes at the mRNA level by qPCR and at the protein level by semi-quantitative immunofluorescence. The upregulation of these genes might reflect a compensatory induction of acylCer biosynthesis as a part of a global barrier repair response in the patient's epidermis.
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Affiliation(s)
- Hanqian Zhang
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
| | - Maja Ericsson
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
| | - Simone Weström
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
| | - Anders Vahlquist
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
| | - Marie Virtanen
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
| | - Hans Törmä
- Department of Medical Sciences, Dermatology and Venereology, Uppsala University, Uppsala, Sweden
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18
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Affiliation(s)
- Laszlo Lorand
- Department of Cell and Molecular BiologyNorthwestern University Feinberg School of Medicine Chicago Illinois USA
| | - Siiri E. Iismaa
- Molecular Cardiology and Biophysics DivisionVictor Chang Cardiac Research Institute Darlinghurst New South Wales Australia
- St Vincent's Clinical SchoolUniversity of New South Wales Kensington New South Wales Australia
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Kárpáti S, Sárdy M, Németh K, Mayer B, Smyth N, Paulsson M, Traupe H. Transglutaminases in autoimmune and inherited skin diseases: The phenomena of epitope spreading and functional compensation. Exp Dermatol 2018; 27:807-814. [PMID: 28940785 DOI: 10.1111/exd.13449] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2017] [Indexed: 02/06/2023]
Abstract
Transglutaminases (TGs) are structurally and functionally related enzymes that modify the post-translational structure and activity of proteins or peptides, and thus are able to turn on or switch off their function. Depending on location and activities, TGs are able to modify the signalling, the function and the fate of cells and extracellular connective tissues. Besides mouse models, human diseases enable us to appreciate the function of various TGs. In this study, skin diseases induced by genetic damages or autoimmune targeting of these enzymes will be discussed. TG1, TG3 and TG5 contribute to the cutaneous barrier and thus to the integrity and function of epidermis. TGM1 mutations related to autosomal recessive ichthyosis subtypes, TGM5 mutations to a mild epidermolysis bullosa phenotype and as novelty TGM3 mutation to uncombable hair syndrome will be discussed. Autoimmunity to TG2, TG3 and TG6 may develop in a few of those genetically determined individuals who lost tolerance to gluten, and manifest as coeliac disease, dermatitis herpetiformis or gluten-dependent neurological symptoms, respectively. These gluten responder diseases commonly occur in combination. In autoimmune diseases, the epitope spreading is remarkable, while in some inherited pathologies, a unique compensation of the lost enzyme function is noted.
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Affiliation(s)
- Sarolta Kárpáti
- Dermatology, Venereology and Dermatooncology, Semmelweis University, Budapest, Hungary
| | - Miklós Sárdy
- Dermatology, Venereology and Dermatooncology, Semmelweis University, Budapest, Hungary
| | - Krisztián Németh
- Dermatology, Venereology and Dermatooncology, Semmelweis University, Budapest, Hungary
| | - Balázs Mayer
- Dermatology, Venereology and Dermatooncology, Semmelweis University, Budapest, Hungary
| | - Neil Smyth
- Biological Sciences, University of Southampton, Southampton, UK
| | - Mats Paulsson
- Center for Biochemistry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Heiko Traupe
- Department of Dermatology, University of Münster, Münster, Germany
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20
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Vahlquist A, Fischer J, Törmä H. Inherited Nonsyndromic Ichthyoses: An Update on Pathophysiology, Diagnosis and Treatment. Am J Clin Dermatol 2018; 19:51-66. [PMID: 28815464 PMCID: PMC5797567 DOI: 10.1007/s40257-017-0313-x] [Citation(s) in RCA: 107] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hereditary ichthyoses are due to mutations on one or both alleles of more than 30 different genes, mainly expressed in the upper epidermis. Syndromic as well as nonsyndromic forms of ichthyosis exist. Irrespective of etiology, virtually all types of ichthyosis exhibit a defective epidermal barrier that constitutes the driving force for hyperkeratosis, skin scaling, and inflammation. In nonsyndromic forms, these features are most evident in severe autosomal recessive congenital ichthyosis (ARCI) and epidermolytic ichthyosis, but to some extent also occur in the common type of non-congenital ichthyosis. A correct diagnosis of ichthyosis-essential not only for genetic counseling but also for adequate patient information about prognosis and therapeutic options-is becoming increasingly feasible thanks to recent progress in genetic knowledge and DNA sequencing methods. This paper reviews the most important aspects of nonsyndromic ichthyoses, focusing on new knowledge about the pathophysiology of the disorders, which will hopefully lead to novel ideas about therapy.
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Affiliation(s)
- Anders Vahlquist
- Department of Medical Sciences, Dermatology, Uppsala University, Uppsala, Sweden
| | - Judith Fischer
- Institute of Human Genetics, University Medical Centre, Freiburg, Germany
| | - Hans Törmä
- Department of Medical Sciences, Dermatology, Uppsala University, Uppsala, Sweden.
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21
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Grond S, Radner FPW, Eichmann TO, Kolb D, Grabner GF, Wolinski H, Gruber R, Hofer P, Heier C, Schauer S, Rülicke T, Hoefler G, Schmuth M, Elias PM, Lass A, Zechner R, Haemmerle G. Skin Barrier Development Depends on CGI-58 Protein Expression during Late-Stage Keratinocyte Differentiation. J Invest Dermatol 2016; 137:403-413. [PMID: 27725204 PMCID: PMC5551682 DOI: 10.1016/j.jid.2016.09.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 08/02/2016] [Accepted: 09/27/2016] [Indexed: 12/12/2022]
Abstract
Adipose triglyceride lipase (ATGL) and its coactivator comparative gene identification-58 (CGI-58) are limiting in cellular triglyceride catabolism. Although ATGL deficiency is compatible with normal skin development, mice globally lacking CGI-58 die postnatally and exhibit a severe epidermal permeability barrier defect, which may originate from epidermal and/or peripheral changes in lipid and energy metabolism. Here, we show that epidermis-specific disruption of CGI-58 is sufficient to provoke a defect in the formation of a functional corneocyte lipid envelope linked to impaired ω-O-acylceramide synthesis. As a result, epidermis-specific CGI-58-deficient mice show severe skin dysfunction, arguing for a tissue autonomous cause of disease development. Defective skin permeability barrier formation in global CGI-58-deficient mice could be reversed via transgenic restoration of CGI-58 expression in differentiated but not basal keratinocytes suggesting that CGI-58 is essential for lipid metabolism in suprabasal epidermal layers. The compatibility of ATGL deficiency with normal epidermal function indicated that CGI-58 may stimulate an epidermal triglyceride lipase beyond ATGL required for the adequate provision of fatty acids as a substrate for ω-O-acylceramide synthesis. Pharmacological inhibition of ATGL enzyme activity similarly reduced triglyceride-hydrolytic activities in wild-type and CGI-58 overexpressing epidermis implicating that CGI-58 participates in ω-O-acylceramide biogenesis independent of its role as a coactivator of epidermal triglyceride catabolism.
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Affiliation(s)
- Susanne Grond
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Franz P W Radner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Thomas O Eichmann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Dagmar Kolb
- Center for Medical Research/Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria
| | - Gernot F Grabner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioTechMed-Graz, Microscopy Facility, University of Graz, Graz, Austria
| | - Robert Gruber
- Department of Dermatology, Venereology and Allergology, University of Innsbruck, Innsbruck, Austria
| | - Peter Hofer
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Christoph Heier
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Silvia Schauer
- Institute of Pathology, Medical University of Graz, Graz, Austria; Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Thomas Rülicke
- Institute of Pathology, Medical University of Graz, Graz, Austria
| | - Gerald Hoefler
- BioTechMed-Graz, Microscopy Facility, University of Graz, Graz, Austria; Institute of Pathology, Medical University of Graz, Graz, Austria; Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Matthias Schmuth
- Department of Dermatology, Venereology and Allergology, University of Innsbruck, Innsbruck, Austria
| | - Peter M Elias
- Department of Dermatology, University of California San Francisco, San Francisco, California, USA
| | - Achim Lass
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Graz, Austria.
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22
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Haneda T, Imai Y, Uchiyama R, Jitsukawa O, Yamanishi K. Activation of Molecular Signatures for Antimicrobial and Innate Defense Responses in Skin with Transglutaminase 1 Deficiency. PLoS One 2016; 11:e0159673. [PMID: 27442430 PMCID: PMC4956052 DOI: 10.1371/journal.pone.0159673] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/06/2016] [Indexed: 01/01/2023] Open
Abstract
Mutations of the transglutaminase 1 gene (TGM1) are a major cause of autosomal recessive congenital ichthyoses (ARCIs) that are associated with defects in skin barrier structure and function. However, the molecular processes induced by the transglutaminase 1 deficiency are not fully understood. The aim of the present study was to uncover those processes by analysis of cutaneous molecular signatures. Gene expression profiles of wild-type and Tgm1-/-epidermis were assessed using microarrays. Gene ontology analysis of the data showed that genes for innate defense responses were up-regulated in Tgm1-/-epidermis. Based on that result, the induction of Il1b and antimicrobial peptide genes, S100a8, S100a9, Defb14, Camp, Slpi, Lcn2, Ccl20 and Wfdc12, was confirmed by quantitative real-time PCR. A protein array revealed that levels of IL-1β, G-CSF, GM-CSF, CXCL1, CXCL2, CXCL9 and CCL2 were increased in Tgm1-/-skin. Epidermal growth factor receptor (EGFR) ligand genes, Hbegf, Areg and Ereg, were activated in Tgm1-/-epidermis. Furthermore, the antimicrobial activity of an epidermal extract from Tgm1-/-mice was significantly increased against both Escherichia coli and Staphylococcus aureus. In the epidermis of ichthyosiform skins from patients with TGM1 mutations, S100A8/9 was strongly positive. The expression of those antimicrobial and defense response genes was also increased in the lesional skin of an ARCI patient with TGM1 mutations. These results suggest that the up-regulation of molecular signatures for antimicrobial and innate defense responses is characteristic of skin with a transglutaminase 1 deficiency, and this autonomous process might be induced to reinforce the defective barrier function of the skin.
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Affiliation(s)
- Takashi Haneda
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Yasutomo Imai
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Ryosuke Uchiyama
- Department of Microbiology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Orie Jitsukawa
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
| | - Kiyofumi Yamanishi
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan
- * E-mail:
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23
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Kumar V, Bouameur JE, Bär J, Rice RH, Hornig-Do HT, Roop DR, Schwarz N, Brodesser S, Thiering S, Leube RE, Wiesner RJ, Vijayaraj P, Brazel CB, Heller S, Binder H, Löffler-Wirth H, Seibel P, Magin TM. A keratin scaffold regulates epidermal barrier formation, mitochondrial lipid composition, and activity. J Cell Biol 2016; 211:1057-75. [PMID: 26644517 PMCID: PMC4674273 DOI: 10.1083/jcb.201404147] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epidermal keratin filaments are important components and organizers of the cornified envelope and regulate mitochondrial metabolism by modulating their membrane composition. Keratin intermediate filaments (KIFs) protect the epidermis against mechanical force, support strong adhesion, help barrier formation, and regulate growth. The mechanisms by which type I and II keratins contribute to these functions remain incompletely understood. Here, we report that mice lacking all type I or type II keratins display severe barrier defects and fragile skin, leading to perinatal mortality with full penetrance. Comparative proteomics of cornified envelopes (CEs) from prenatal KtyI−/− and KtyII−/−K8 mice demonstrates that absence of KIF causes dysregulation of many CE constituents, including downregulation of desmoglein 1. Despite persistence of loricrin expression and upregulation of many Nrf2 targets, including CE components Sprr2d and Sprr2h, extensive barrier defects persist, identifying keratins as essential CE scaffolds. Furthermore, we show that KIFs control mitochondrial lipid composition and activity in a cell-intrinsic manner. Therefore, our study explains the complexity of keratinopathies accompanied by barrier disorders by linking keratin scaffolds to mitochondria, adhesion, and CE formation.
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Affiliation(s)
- Vinod Kumar
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Jamal-Eddine Bouameur
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Janina Bär
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Robert H Rice
- Department of Environmental Toxicology, University of California, Davis, Davis, CA 95616
| | - Hue-Tran Hornig-Do
- Center for Physiology and Pathophysiology, Institute for Vegetative Physiology, University of Cologne, 50931 Cologne, Germany
| | - Dennis R Roop
- Department of Dermatology, University of Colorado, Denver, CO 80045 Charles C. Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado, Denver, CO 80045
| | - Nicole Schwarz
- Institute of Molecular and Cellular Anatomy, Rheinisch-Westfälische Technische Hochschule Aachen University, 52074 Aachen, Germany
| | - Susanne Brodesser
- Center for Physiology and Pathophysiology, Institute for Vegetative Physiology, University of Cologne, 50931 Cologne, Germany Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, Medical Faculty, University of Cologne, 50931 Cologne, Germany Center for Molecular Medicine Cologne, 50931 Cologne, Germany
| | - Sören Thiering
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Rudolf E Leube
- Institute of Molecular and Cellular Anatomy, Rheinisch-Westfälische Technische Hochschule Aachen University, 52074 Aachen, Germany
| | - Rudolf J Wiesner
- Center for Physiology and Pathophysiology, Institute for Vegetative Physiology, University of Cologne, 50931 Cologne, Germany Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases, Medical Faculty, University of Cologne, 50931 Cologne, Germany Center for Molecular Medicine Cologne, 50931 Cologne, Germany
| | | | - Christina B Brazel
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
| | - Sandra Heller
- Center for Biotechnology and Biomedicine, 04103 Leipzig, Germany
| | - Hans Binder
- Interdisciplinary Centre for Bioinformatics, University of Leipzig, 04107 Leipzig, Germany
| | - Henry Löffler-Wirth
- Interdisciplinary Centre for Bioinformatics, University of Leipzig, 04107 Leipzig, Germany
| | - Peter Seibel
- Center for Biotechnology and Biomedicine, 04103 Leipzig, Germany
| | - Thomas M Magin
- Translational Centre for Regenerative Medicine Leipzig, University of Leipzig, 04103 Leipzig, Germany Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, 04103 Leipzig, Germany
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24
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The role of barrier genes in epidermal malignancy. Oncogene 2016; 35:5705-5712. [PMID: 27041586 DOI: 10.1038/onc.2016.84] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 02/17/2016] [Accepted: 02/18/2016] [Indexed: 12/24/2022]
Abstract
The outermost layer of the mammalian skin, the epidermis, forms a protective barrier against pathogenic microbes and tissue dehydration. This barrier is formed and maintained by complex genetic networks that connect cellular differentiation processes, enzymatic activities and cellular junctions. Disruption in these networks affects the balance between keratinocyte proliferation and differentiation resulting in barrier function impairment, epidermal hyperproliferation and in some cases, squamous cell carcinoma (SCC). Recent studies in wound-induced inflammation-mediated cancers in mice have identified dysregulation of core barrier components as tumor drivers. We therefore propose a hypothesis in which loss of key barrier genes, induce barrier dysfunction, and promote inflammation-driven epidermal hyperplasia and carcinogenesis over time. This emerging vision suggests that under specific genetic circumstances, localized barrier impairment could be considered as a hallmark of initiating lesions in epidermal SCC.
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25
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Cyclic Alopecia and Abnormal Epidermal Cornification in Zdhhc13-Deficient Mice Reveal the Importance of Palmitoylation in Hair and Skin Differentiation. J Invest Dermatol 2015; 135:2603-2610. [PMID: 26121212 DOI: 10.1038/jid.2015.240] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 05/28/2015] [Accepted: 06/16/2015] [Indexed: 12/11/2022]
Abstract
Many biochemical pathways involved in hair and skin development have not been investigated. Here, we reported on the lesions and investigated the mechanism underlying hair and skin abnormalities in Zdhhc13(skc4) mice with a deficiency in DHHC13, a palmitoyl-acyl transferase encoded by Zdhhc13. Homozygous affected mice showed ragged and dilapidated cuticle of the hair shaft (CUH, a hair anchoring structure), poor hair anchoring ability, and premature hair loss at early telogen phase of the hair cycle, resulting in cyclic alopecia. Furthermore, the homozygous affected mice exhibited hyperproliferation of the epidermis, disturbed cornification, fragile cornified envelope (CE, a skin barrier structure), and impaired skin barrier function. Biochemical investigations revealed that cornifelin, which contains five palmitoylation sites at cysteine residues (C58, C59, C60, C95, and C101), was a specific substrate of DHHC13 and that it was absent in the CUH and CE structures of the affected mice. Furthermore, cornifelin levels were markedly reduced when two palmitoylated cysteines were replaced with serine (C95S and C101S). Taken together, our results suggest that DHHC13 is important for hair anchoring and skin barrier function and that cornifelin deficiency contributes to cyclic alopecia and skin abnormalities in Zdhhc13(skc4) mice.
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26
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Kim J, Liu Y, Qiu M, Xu Y. Pluripotency factor Nanog is tumorigenic by deregulating DNA damage response in somatic cells. Oncogene 2015; 35:1334-40. [DOI: 10.1038/onc.2015.205] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 03/27/2015] [Accepted: 04/14/2015] [Indexed: 12/19/2022]
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Muenyi CS, Carrion SL, Jones LA, Kennedy LH, Slominski AT, Sutter CH, Sutter TR. Effects of in utero exposure of C57BL/6J mice to 2,3,7,8-tetrachlorodibenzo-p-dioxin on epidermal permeability barrier development and function. ENVIRONMENTAL HEALTH PERSPECTIVES 2014; 122:1052-1058. [PMID: 24904982 PMCID: PMC4181931 DOI: 10.1289/ehp.1308045] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 06/04/2014] [Indexed: 05/29/2023]
Abstract
BACKGROUND Development of the epidermal permeability barrier (EPB) is essential for neonatal life. Defects in this barrier are found in many skin diseases such as atopic dermatitis. OBJECTIVE We investigated the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the development and function of the EPB. METHODS Timed-pregnant C57BL/6J mice were gavaged with corn oil or TCDD (10 μg/kg body weight) on gestation day 12. Embryos were harvested on embryonic day (E) 15, E16, E17, and postnatal day (PND) 1. RESULTS A skin permeability assay showed that TCDD accelerated the development of the EPB, beginning at E15. This was accompanied by a significant decrease in transepidermal water loss (TEWL), enhanced stratification, and formation of the stratum corneum (SC). The levels of several ceramides were significantly increased at E15 and E16. PND1 histology revealed TCDD-induced acanthosis and epidermal hyperkeratosis. This was accompanied by disrupted epidermal tight junction (TJ) function, with increased dye leakage at the terminal claudin-1-staining TJs of the stratum granulosum. Because the animals did not have enhanced rates of TEWL, a commonly observed phenotype in animals with TJ defects, we performed tape-stripping. Removal of most of the SC resulted in a significant increase in TEWL in TCDD-exposed PND1 pups compared with their control group. CONCLUSIONS These findings demonstrate that in utero exposure to TCDD accelerates the formation of an abnormal EPB with leaky TJs, warranting further study of environmental exposures, epithelial TJ integrity, and atopic disease.
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Bains W. Transglutaminse 2 and EGGL, the protein cross-link formed by transglutaminse 2, as therapeutic targets for disabilities of old age. Rejuvenation Res 2013; 16:495-517. [PMID: 23968147 PMCID: PMC3869435 DOI: 10.1089/rej.2013.1452] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 08/22/2013] [Indexed: 12/17/2022] Open
Abstract
Aging of the extracellular matrix (ECM), the protein matrix that surrounds and penetrates the tissues and binds the body together, contributes significantly to functional aging of tissues. ECM proteins become increasingly cross-linked with age, and this cross-linking is probably important in the decline of the ECM's function. This article reviews the role of ε-(γ-glutamyl)-lysine (EGGL), a cross-link formed by transglutaminase enzymes, and particularly the widely expressed isozyme transglutaminase 2 (TG2), in the aging ECM. There is little direct data on EGGL accumulation with age, and no direct evidence of a role of EGGL in the aging of the ECM with pathology. However, several lines of circumstantial evidence suggest that EGGL accumulates with age, and its association with pathology suggests that this might reflect degradation of ECM function. TG activity increases with age in many circumstances. ECM protein turnover is such that some EGGL made by TG is likely to remain in place for years, if not decades, in healthy tissue, and both EGGL and TG levels are enhanced by age-related diseases. If further research shows EGGL does accumulate with age, removing it could be of therapeutic benefit. Also reviewed is the blockade of TG and active removal of EGGL as therapeutic strategies, with the conclusion that both have promise. EGGL removal may have benefit for acute fibrotic diseases, such as tendinopathy, and for treating generalized decline in ECM function with old age. Extracellular TG2 and EGGL are therefore therapeutic targets both for specific and more generalized diseases of aging.
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Affiliation(s)
- William Bains
- SRF Laboratory, Department of Chemical Engineering and Biotechnology, University of Cambridge , Cambridge, United Kingdom
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Eckhart L, Lippens S, Tschachler E, Declercq W. Cell death by cornification. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:3471-3480. [DOI: 10.1016/j.bbamcr.2013.06.010] [Citation(s) in RCA: 288] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 06/07/2013] [Accepted: 06/08/2013] [Indexed: 01/05/2023]
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Traupe H, Fischer J, Oji V. Nonsyndromic types of ichthyoses - an update. J Dtsch Dermatol Ges 2013; 12:109-21. [DOI: 10.1111/ddg.12229] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 08/29/2013] [Indexed: 01/05/2023]
Affiliation(s)
- Heiko Traupe
- Department of Dermatology; University of Münster; Germany
| | - Judith Fischer
- Institute for Human Genetics; University Hospital of Freiburg, Freiburg im Breisgau; Germany
| | - Vinzenz Oji
- Department of Dermatology; University of Münster; Germany
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Aufenvenne K, Larcher F, Hausser I, Duarte B, Oji V, Nikolenko H, Del Rio M, Dathe M, Traupe H. Topical enzyme-replacement therapy restores transglutaminase 1 activity and corrects architecture of transglutaminase-1-deficient skin grafts. Am J Hum Genet 2013; 93:620-30. [PMID: 24055110 DOI: 10.1016/j.ajhg.2013.08.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Revised: 07/17/2013] [Accepted: 08/01/2013] [Indexed: 11/19/2022] Open
Abstract
Transglutaminase-1 (TG1)-deficient autosomal-recessive congenital ichthyosis (ARCI) is a rare and severe genetic skin disease caused by mutations in TGM1. It is characterized by collodion babies at birth, dramatically increased transepidermal water loss (TEWL), and lifelong pronounced scaling. The disease has a tremendous burden, including the problem of stigmatization. Currently, no therapy targeting the molecular cause is available, and the therapeutic situation is deplorable. In this study, we developed the basis for a causative therapy aiming at the delivery of the enzyme to the inner site of the keratinocytes' plasma membrane. We prepared sterically stabilized liposomes with encapsulated recombinant human TG1 (rhTG1) and equipped with a highly cationic lipopeptide vector to mediate cellular uptake. The liposomes overcame the problems of insufficient cutaneous delivery and membrane penetration and provided excellent availability and activity of rhTG1 in primary keratinocytes. To demonstrate the general feasibility of this therapeutic approach in a humanized context, we used a skin-humanized mouse model. Treatment with rhTG1 liposomes resulted in considerable improvement of the ichthyosis phenotype and in normalization of the regenerated ARCI skin: in situ monitoring showed a restoration of TG1 activity, and cholesterol clefts vanished ultrastructurally. Measurement of TEWL revealed a restoration of epidermal barrier function. We regard this aspect as a major advance over available nonspecific approaches making use of, for example, retinoid creams. We conclude that this topical approach is a promising strategy for restoring epidermal integrity and barrier function and provides a causal cure for individuals with TG1 deficiency.
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Affiliation(s)
- Karin Aufenvenne
- Department of Dermatology, University Hospital Münster, 48149 Münster, Germany.
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Identifying a hyperkeratosis signature in autosomal recessive congenital ichthyosis: Mdm2 inhibition prevents hyperkeratosis in a rat ARCI model. J Invest Dermatol 2013; 134:858-861. [PMID: 24005053 DOI: 10.1038/jid.2013.374] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Terrinoni A, Serra V, Codispoti A, Talamonti E, Bui L, Palombo R, Sette M, Campione E, Didona B, Annicchiarico-Petruzzelli M, Zambruno G, Melino G, Candi E. Novel transglutaminase 1 mutations in patients affected by lamellar ichthyosis. Cell Death Dis 2012; 3:e416. [PMID: 23096117 PMCID: PMC3481139 DOI: 10.1038/cddis.2012.152] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Lamellar Ichthyosis (LI) is a form of congenital ichthyosis that is caused by mutations in the TGM1 gene that encodes for the transglutaminase 1 (TG1) enzyme. Functional inactivation of TG1 could be due to mutations, deletion or insertions. In this study, we have screened 16 patients affected by LI and found six new mutations: two transition/transversion (R37G, V112A), two nonsense mutations and two putative splice site both leading to a premature stop codon. The mutations are localized in exons 2 (N-terminal domain), 5, 11 (central catalytic domain), and none is located in the two beta-barrel C-terminal domains. In conclusion, this study expands the current knowledge on TGM1 mutation spectrum, increasing the characterization of mutations would provide more accurate prenatal genetic counselling for parents at-risk individuals.
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Affiliation(s)
- A Terrinoni
- IDI-IRCCS c/o Department of Experimental Medicine and Surgery, University of Tor Vergata, Rome, Italy
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Mulder KW, Wang X, Escriu C, Ito Y, Schwarz RF, Gillis J, Sirokmány G, Donati G, Uribe-Lewis S, Pavlidis P, Murrell A, Markowetz F, Watt FM. Diverse epigenetic strategies interact to control epidermal differentiation. Nat Cell Biol 2012; 14:753-63. [PMID: 22729083 DOI: 10.1038/ncb2520] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 05/10/2012] [Indexed: 12/13/2022]
Abstract
It is becoming clear that interconnected functional gene networks, rather than individual genes, govern stem cell self-renewal and differentiation. To identify epigenetic factors that impact on human epidermal stem cells we performed siRNA-based genetic screens for 332 chromatin modifiers. We developed a Bayesian mixture model to predict putative functional interactions between epigenetic modifiers that regulate differentiation. We discovered a network of genetic interactions involving EZH2, UHRF1 (both known to regulate epidermal self-renewal), ING5 (a MORF complex component), BPTF and SMARCA5 (NURF complex components). Genome-wide localization and global mRNA expression analysis revealed that these factors impact two distinct but functionally related gene sets, including integrin extracellular matrix receptors that mediate anchorage of epidermal stem cells to their niche. Using a competitive epidermal reconstitution assay we confirmed that ING5, BPTF, SMARCA5, EZH2 and UHRF1 control differentiation under physiological conditions. Thus, regulation of distinct gene expression programs through the interplay between diverse epigenetic strategies protects epidermal stem cells from differentiation.
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Affiliation(s)
- Klaas W Mulder
- Epithelial Cell Biology Group, Cancer Research UK Cambridge Research Institute, Robinson Way, Cambridge CB2 0RE, UK.
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Franzke CW, Cobzaru C, Triantafyllopoulou A, Löffek S, Horiuchi K, Threadgill DW, Kurz T, van Rooijen N, Bruckner-Tuderman L, Blobel CP. Epidermal ADAM17 maintains the skin barrier by regulating EGFR ligand-dependent terminal keratinocyte differentiation. ACTA ACUST UNITED AC 2012; 209:1105-19. [PMID: 22565824 PMCID: PMC3371728 DOI: 10.1084/jem.20112258] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
ADAM17 (a disintegrin and metalloproteinase 17) is ubiquitously expressed and cleaves membrane proteins, such as epidermal growth factor receptor (EGFR) ligands, l-selectin, and TNF, from the cell surface, thus regulating responses to tissue injury and inflammation. However, little is currently known about its role in skin homeostasis. We show that mice lacking ADAM17 in keratinocytes (A17(ΔKC)) have a normal epidermal barrier and skin architecture at birth but develop pronounced defects in epidermal barrier integrity soon after birth and develop chronic dermatitis as adults. The dysregulated expression of epidermal differentiation proteins becomes evident 2 d after birth, followed by reduced transglutaminase (TGM) activity, transepidermal water loss, up-regulation of the proinflammatory cytokine IL-36α, and inflammatory immune cell infiltration. Activation of the EGFR was strongly reduced in A17(ΔKC) skin, and topical treatment of A17(ΔKC) mice with recombinant TGF-α significantly improved TGM activity and decreased skin inflammation. Finally, we show that mice lacking the EGFR in keratinocytes (Egfr(ΔKC)) closely resembled A17(ΔKC) mice. Collectively, these results identify a previously unappreciated critical role of the ADAM17-EGFR signaling axis in maintaining the homeostasis of the postnatal epidermal barrier and suggest that this pathway could represent a good target for treatment of epidermal barrier defects.
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Affiliation(s)
- Claus-Werner Franzke
- Department of Dermatology, University Freiburg Medical Center, D-79104 Freiburg, Germany.
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Hou M, Man M, Man W, Zhu W, Hupe M, Park K, Crumrine D, Elias PM, Man MQ. Topical hesperidin improves epidermal permeability barrier function and epidermal differentiation in normal murine skin. Exp Dermatol 2012; 21:337-40. [PMID: 22509829 PMCID: PMC3335754 DOI: 10.1111/j.1600-0625.2012.01455.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Orange peel extract appears to exhibit beneficial effects on skin whitening, inflammation, UVB protection, as well as keratinocyte proliferation. In the present study, we determine whether topical hesperidin influences epidermal permeability barrier function and its underlying mechanisms. Hairless mice were treated topically with 2% hesperidin or 70% ethanol alone twice daily for 6 days. At the end of treatment, basal transepidermal water loss (TEWL) was measured 2 and 4 h post barrier disruption. Epidermal proliferation and differentiation were evaluated by immunohistochemical staining and Western blot analysis. Additionally, lamellar body density and secretion were assessed by electron microscopy. Although there were no significant differences in basal barrier function, in comparison with control animals, topical hesperidin significantly accelerated barrier recovery at both 2 and 4 h after acute barrier abrogation. Enhanced barrier function in hesperidin-treated skin correlated with stimulation of both epidermal proliferation and differentiation, as well as enhanced lamellar body secretion. These results indicate that topical hesperidin enhances epidermal permeability barrier homeostasis at least in part due to stimulation of epidermal proliferation, differentiation, as well as lamellar body secretion.
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Affiliation(s)
- Maihua Hou
- Department of Dermatology, Nanjing Medical University, Nanjing, P. R. China
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Mona Man
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Wenyan Man
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Wenyuan Zhu
- Department of Dermatology, Nanjing Medical University, Nanjing, P. R. China
| | - Melanie Hupe
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Kyungho Park
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Debra Crumrine
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Peter M. Elias
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
| | - Mao-Qiang Man
- Dermatology Service, Veterans Affairs Medical Center, and Department of Dermatology, University of California, San Francisco, CA 94121, USA
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John S, Thiebach L, Frie C, Mokkapati S, Bechtel M, Nischt R, Rosser-Davies S, Paulsson M, Smyth N. Epidermal transglutaminase (TGase 3) is required for proper hair development, but not the formation of the epidermal barrier. PLoS One 2012; 7:e34252. [PMID: 22496784 PMCID: PMC3319564 DOI: 10.1371/journal.pone.0034252] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 02/24/2012] [Indexed: 02/07/2023] Open
Abstract
Transglutaminases (TGase), a family of cross-linking enzymes present in most cell types, are important in events as diverse as cell-signaling and matrix stabilization. Transglutaminase 1 is crucial in developing the epidermal barrier, however the skin also contains other family members, in particular TGase 3. This isoform is highly expressed in the cornified layer, where it is believed to stabilize the epidermis and its reduction is implicated in psoriasis. To understand the importance of TGase 3 in vivo we have generated and analyzed mice lacking this protein. Surprisingly, these animals display no obvious defect in skin development, no overt changes in barrier function or ability to heal wounds. In contrast, hair lacking TGase 3 is thinner, has major alterations in the cuticle cells and hair protein cross-linking is markedly decreased. Apparently, while TGase 3 is of unique functional importance in hair, in the epidermis loss of TGase 3 can be compensated for by other family members.
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Affiliation(s)
- Susan John
- Center for Biochemistry, University of Cologne, Cologne, North Rhine-Westphalia, Germany.
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38
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Long-term faithful recapitulation of transglutaminase 1-deficient lamellar ichthyosis in a skin-humanized mouse model, and insights from proteomic studies. J Invest Dermatol 2012; 132:1918-21. [PMID: 22437313 PMCID: PMC3375344 DOI: 10.1038/jid.2012.65] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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Nakagawa N, Yamamoto M, Imai Y, Sakaguchi Y, Takizawa T, Ohta N, Yagi N, Hatta I, Hitomi K, Takizawa T, Takeda J, Tsuda T, Matsuki M, Yamanishi K. Knocking-in the R142C mutation in transglutaminase 1 disrupts the stratum corneum barrier and postnatal survival of mice. J Dermatol Sci 2011; 65:196-206. [PMID: 22258055 DOI: 10.1016/j.jdermsci.2011.12.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 11/18/2011] [Accepted: 12/07/2011] [Indexed: 10/14/2022]
Abstract
BACKGROUND Mutations in the gene encoding transglutaminase 1 (TG1) are responsible for various types of autosomal recessive congenital ichthyosis (ARCI), such as lamellar ichthyosis (LI), congenital ichthyosiform erythroderma (CIE) and some minor variants of ARCI. A point mutation of R143C in the β-sandwich domain of TG1 has been often identified in patients with LI or CIE. OBJECTIVE To elucidate the effect of that point mutation on skin barrier structures and functions, we generated mice with a point mutation of R142C, which corresponds to the R143C mutation in human TG1. METHODS A mouse line with the R142C point mutation in TG1 was established using a gene targeting technique and the Cre-loxP system. The skin phenotypes were analyzed in homozygous mutant Tgm1(R142C/R142C) mice. RESULTS In the skin of Tgm1(R142C/R142C) mice, expression of the mutant transcripts was comparable with wild-type or Tgm1(+/R142C) mice. However, the amount of mutated protein in the skin was markedly decreased in Tgm1(R142C/R142C) mice, and the TG1 activity of Tgm1(R142C/R142C) keratinocytes was almost lost. Tgm1(R142C/R142C) mice exhibited morphological and functional skin barrier defects and neonatal lethality. The stratum corneum of those mice lacked cornified envelopes, and loricrin, the major structural component, failed to assemble at the corneocyte cell periphery. Tgm1(R142C/R142C) mice showed a marked increase in transepidermal water loss and their skin was easily permeable to toluidine blue dye. The intercellular lipid lamellar structures of the stratum corneum were irregular and the 13-nm periodic X-ray diffractions from the stratum corneum lipid molecules were lost in vivo. CONCLUSION From these results, we suggest that the R142C mutation of TG1 reduces the enzyme stability which is indispensable for development of the stratum corneum and skin barrier function and for postnatal survival of mice.
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Affiliation(s)
- Noboru Nakagawa
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Hyogo 663-8501, Japan
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Deasey S, Shanmugasundaram S, Nurminskaya M. Tissue-specific responses to loss of transglutaminase 2. Amino Acids 2011; 44:179-87. [PMID: 22194042 DOI: 10.1007/s00726-011-1183-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 11/22/2011] [Indexed: 11/27/2022]
Abstract
Of the eight catalytic transglutaminases (TGs), transglutaminase 2 (TG2) has been the most comprehensively studied due to its ubiquitous expression in multiple cell types. Despite the observed critical role for this enzyme in multiple biological processes in vitro, TG2 knockout mouse models have shown no severe developmental phenotypes, suggesting compensation by other TGs. To begin characterization of the compensating mechanisms, we analyzed total transamidating activity and expression patterns of all catalytically active TGs in seven different tissues/organs from wild-type and TG2 knockout mice. Inhibitory analysis with TG2-specific inhibitor KCC-009 suggests that relative contribution of TG2 in total transamidating activity differs in various tissues. Accordingly, our data indicate tissue-specific mechanisms of compensation for the loss of TG2, including transcriptional compensation in heart and liver versus functional compensation in aorta, kidney and skeletal/cartiagenous tissues. On the contrary, no compensation has been detected in skeletal muscle, suggesting a limited role for the TG2-mediated transamidation in normal development of this tissue.
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Affiliation(s)
- Stephanie Deasey
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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Blanchet-Bardon C, Tadini G, Machado Matos M, Delarue A. Association of glycerol and paraffin in the treatment of ichthyosis in children: an international, multicentric, randomized, controlled, double-blind study. J Eur Acad Dermatol Venereol 2011; 26:1014-9. [PMID: 22118417 DOI: 10.1111/j.1468-3083.2011.04304.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Efficacy and tolerance should be considered in topical treatments of chronicle affections with impaired skin barrier function such as ichthyosis. OBJECTIVES To demonstrate the efficacy of Dexeryl in reducing severity of ichthyosis. METHODS A prospective, multicentre, randomized, placebo controlled study was performed with patients under 18 years suffering from a non-bullous form of ichthyosis. A double-blind period using Dexeryl (an emollient cream containing glycerol 15% and paraffin 10%) or placebo (its vehicle) during 4 weeks followed by an open label period with all patients treated by Dexeryl for 8 weeks. Improvement of ichthyosis was assessed by cutaneous xerosis evolution (SRRC score): the percentage of patients with 50% reduction of the SRRC score at D28 was the primary criterion. The assessment of pruritus [visual analogue scale (VAS)], global evaluation and safety were secondary. RESULTS The percentage of patients with at least 50% reduction of SRRC score at D28 was significantly higher in Dexeryl group (60.3%) vs. vehicle group (43.5%; P = 0.008). Reduction of pruritus on VAS was significantly higher at D28 with Dexeryl (-2.16) compared to that in placebo (-1.49), P < 0.05. The improvement continues through the open label period: at D84 we observed -2.5 of SRRC score in the Dexeryl group vs.-1.8 for the group previously treated by vehicle. Investigators found Dexeryl efficacy as satisfying for about 80% of treated patients vs. 50% with vehicle. Concerning safety, most of the adverse events were not related to treatment. CONCLUSIONS Dexeryl showed a significant improvement of xerosis and related symptoms in children with ichthyosis and was well tolerated.
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Affiliation(s)
- K Natsuga
- Department of Dermatology, Hokkaido University Graduate School of Medicine, North 15 West 7, Sapporo 060-8638, Japan.
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Abstract
Upon barrier disturbance, adult CD44 knockout (KO) mice show delayed recovery of epidermal barrier function. This correlates with the loss of apical polarization of lamellar body (LB) secretion. As tight junctions (TJs) are crucial for barrier function and regulate polarized targeting of vesicles, we hypothesized that CD44 regulates TJs and associated cell polarity complexes, which in turn contributes to altered skin barrier function in CD44 KO mice. We show a delay in embryonic barrier formation associated with a loss of apical LB localization in CD44 KO mice, which correlates with alterations in TJ proteins and Par3. Simultaneously, the activity of Rac1, a major regulator of TJ barrier function, was reduced. Importantly, normalization of barrier function at E18.5 coincided with the recovery of these proteins. Tape-stripping experiments revealed that the loss of CD44 also affected TJ proteins upon induced disturbance of the barrier in adult mice. In CD44 KO keratinocytes, cell polarization and TJ barrier function were impaired. An alteration of differentiation markers was also observed, but was less pronounced than alterations of TJ proteins. Taken together, the results reveal an important function for CD44 in the assembly and function of TJs, suggesting their involvement in the skin barrier phenotype of CD44 KO mice.
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44
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Jiang H, Jans R, Xu W, Rorke EA, Lin CY, Chen YW, Fang S, Zhong Y, Eckert RL. Type I transglutaminase accumulation in the endoplasmic reticulum may be an underlying cause of autosomal recessive congenital ichthyosis. J Biol Chem 2010; 285:31634-46. [PMID: 20663883 DOI: 10.1074/jbc.m110.128645] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Type I transglutaminase (TG1) is an enzyme that is responsible for assembly of the keratinocyte cornified envelope. Although TG1 mutation is an underlying cause of autosomal recessive congenital ichthyosis, a debilitating skin disease, the pathogenic mechanism is not completely understood. In the present study we show that TG1 is an endoplasmic reticulum (ER) membrane-associated protein that is trafficked through the ER for ultimate delivery to the plasma membrane. Mutation severely attenuates this processing and a catalytically inactive point mutant, TG1-FLAG(C377A), accumulates in the endoplasmic reticulum and in aggresome-like structures where it is ubiquitinylated. This accumulation results from protein misfolding, as treatment with a chemical chaperone permits it to exit the endoplasmic reticulum and travel to the plasma membrane. ER accumulation is also observed for ichthyosis-associated TG1 mutants. Our findings suggest that misfolding of TG1 mutants leads to ubiquitinylation and accumulation in the ER and aggresomes, and that abnormal intracellular processing of TG1 mutants may be an underlying cause of ichthyosis.
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Affiliation(s)
- Haibing Jiang
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA
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Yanagi T, Akiyama M, Nishihara H, Ishikawa J, Sakai K, Miyamura Y, Naoe A, Kitahara T, Tanaka S, Shimizu H. Self-improvement of keratinocyte differentiation defects during skin maturation in ABCA12-deficient harlequin ichthyosis model mice. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:106-18. [PMID: 20489143 DOI: 10.2353/ajpath.2010.091120] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Harlequin ichthyosis (HI) is caused by loss-of-function mutations in the keratinocyte lipid transporter ABCA12. The patients often die in the first 1 or 2 weeks of life, although HI survivors' phenotypes improve within several weeks after birth. In order to clarify the mechanisms of phenotypic recovery, we studied grafted skin and keratinocytes from Abca12-disrupted (Abca12(-/-)) mice showing abnormal lipid transport. Abca12(-/-) neonatal epidermis showed significantly reduced total ceramide amounts and aberrant ceramide composition. Immunofluorescence and immunoblotting of Abca12(-/-) neonatal epidermis revealed defective profilaggrin/filaggrin conversion and reduced protein expression of the differentiation-specific molecules, loricrin, kallikrein 5, and transglutaminase 1, although their mRNA expression was up-regulated. In contrast, Abca12(-/-) skin grafts kept in a dry environment exhibited dramatic improvements in all these abnormalities. Increased transepidermal water loss, a parameter representing barrier defect, was remarkably decreased in grafted Abca12(-/-) skin. Ten-passage sub-cultured Abca12(-/-) keratinocytes showed restoration of intact ceramide distribution, differentiation-specific protein expression and profilaggrin/filaggrin conversion, which were defective in primary-cultures. Using cDNA microarray analysis, lipid transporters including four ATP-binding cassette transporters were up-regulated after sub-culture of Abca12(-/-) keratinocytes compared with primary-culture. These results indicate that disrupted keratinocyte differentiation during the fetal development is involved in the pathomechanism of HI and, during maturation, Abca12(-/-) epidermal keratinocytes regain normal differentiation processes. This restoration may account for the skin phenotype improvement observed in HI survivors.
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Affiliation(s)
- Teruki Yanagi
- Department of Dermatology, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo 060-8638, Japan
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O'Shaughnessy RF, Choudhary I, Harper JI. Interleukin-1 alpha blockade prevents hyperkeratosis in an in vitro model of lamellar ichthyosis. Hum Mol Genet 2010; 19:2594-605. [DOI: 10.1093/hmg/ddq145] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Kongsuwan K, Josh P, Colgrave ML, Bagnall NH, Gough J, Burns B, Pearson R. Activation of several key components of the epidermal differentiation pathway in cattle following infestation with the cattle tick, Rhipicephalus (Boophilus) microplus. Int J Parasitol 2010; 40:499-507. [DOI: 10.1016/j.ijpara.2009.10.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Revised: 10/04/2009] [Accepted: 10/08/2009] [Indexed: 12/26/2022]
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O'Shaughnessy RFL, Welti JC, Sully K, Byrne C. Akt-dependent Pp2a activity is required for epidermal barrier formation during late embryonic development. Development 2009; 136:3423-31. [PMID: 19762425 DOI: 10.1242/dev.037010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Acquisition of epidermal barrier function occurs late in mouse gestation. Several days before birth a wave of barrier acquisition sweeps across murine fetal skin, converging on dorsal and ventral midlines. We investigated the molecular pathways active during epidermal barrier formation. Akt signaling increased as the barrier wave crossed epidermis and Jun was transiently dephosphorylated. Inhibitor experiments on embryonic explants showed that the dephosphorylation of Jun was dependent on both Akt and protein phosphatase 2A (Pp2a). Inhibition of Pp2a and Akt signaling also caused defects in epidermal barrier formation. These data are compatible with a model for developmental barrier acquisition mediated by Pp2a regulation of Jun dephosphorylation, downstream of Akt signaling. Support for this model was provided by siRNA-mediated knockdown of Ppp2r2a (Pr55alpha or B55alpha), a regulatory subunit of Pp2a expressed in an Akt-dependent manner in epidermis during barrier formation. Ppp2r2a reduction caused significant increase in Jun phosphorylation and interfered with the acquisition of barrier function, with barrier acquisition being restored by inhibition of Jun phosphorylation. Our data provide strong evidence that Ppp2r2a is a regulatory subunit of Pp2a that targets this phosphatase to Jun, and that Pp2a action is necessary for barrier formation. We therefore describe a novel Akt-dependent Pp2a activity that acts at least partly through Jun to affect initial barrier formation during late embryonic epidermal development.
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Affiliation(s)
- Ryan F L O'Shaughnessy
- Centre for Cutaneous Research, Institute of Cell and Molecular Science, Barts and the London School of Medicine and Dentistry, London, UK.
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Iismaa SE, Mearns BM, Lorand L, Graham RM. Transglutaminases and disease: lessons from genetically engineered mouse models and inherited disorders. Physiol Rev 2009; 89:991-1023. [PMID: 19584319 DOI: 10.1152/physrev.00044.2008] [Citation(s) in RCA: 263] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The human transglutaminase (TG) family consists of a structural protein, protein 4.2, that lacks catalytic activity, and eight zymogens/enzymes, designated factor XIII-A (FXIII-A) and TG1-7, that catalyze three types of posttranslational modification reactions: transamidation, esterification, and hydrolysis. These reactions are essential for biological processes such as blood coagulation, skin barrier formation, and extracellular matrix assembly but can also contribute to the pathophysiology of various inflammatory, autoimmune, and degenerative conditions. Some members of the TG family, for example, TG2, can participate in biological processes through actions unrelated to transamidase catalytic activity. We present here a comprehensive review of recent insights into the physiology and pathophysiology of TG family members that have come from studies of genetically engineered mouse models and/or inherited disorders. The review focuses on FXIII-A, TG1, TG2, TG5, and protein 4.2, as mice deficient in TG3, TG4, TG6, or TG7 have not yet been reported, nor have mutations in these proteins been linked to human disease.
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Affiliation(s)
- Siiri E Iismaa
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute and Universityof New South Wales, Sydney, New South Wales 2010, Australia
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Demehri S, Turkoz A, Kopan R. Epidermal Notch1 loss promotes skin tumorigenesis by impacting the stromal microenvironment. Cancer Cell 2009; 16:55-66. [PMID: 19573812 PMCID: PMC2705757 DOI: 10.1016/j.ccr.2009.05.016] [Citation(s) in RCA: 211] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2008] [Revised: 12/10/2008] [Accepted: 05/05/2009] [Indexed: 01/05/2023]
Abstract
Notch1 is a proto-oncogene in several organs. In the skin, however, Notch1 deletion leads to tumor formation, suggesting that Notch1 is a "tumor suppressor" within this context. Here we demonstrate that, unlike classical tumor suppressors, Notch1 loss in epidermal keratinocytes promotes tumorigenesis non-cell autonomously by impairing skin-barrier integrity and creating a wound-like microenvironment in the skin. Using mice with a chimeric pattern of Notch1 deletion, we determined that Notch1-expressing keratinocytes in this microenvironment readily formed papillomas, showing that Notch1 was insufficient to suppress this tumor-promoting effect. Accordingly, loss of other Notch paralogues that impaired the skin barrier also predisposed Notch1-expressing skin to tumorigenesis, demonstrating that the tumor-promoting effect of Notch1 loss involves a crosstalk between barrier-defective epidermis and its stroma.
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Affiliation(s)
- Shadmehr Demehri
- Department of Developmental Biology and Division of Dermatology, Washington University School of Medicine, Box 8103, 660 South Euclid Avenue, Saint Louis, Missouri 63110-1095, USA
| | - Ahu Turkoz
- Department of Developmental Biology and Division of Dermatology, Washington University School of Medicine, Box 8103, 660 South Euclid Avenue, Saint Louis, Missouri 63110-1095, USA
| | - Raphael Kopan
- Department of Developmental Biology and Division of Dermatology, Washington University School of Medicine, Box 8103, 660 South Euclid Avenue, Saint Louis, Missouri 63110-1095, USA
- Corresponding Author:
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