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Chua CJ, Morrissette-McAlmon J, Tung L, Boheler KR. Understanding Arrhythmogenic Cardiomyopathy: Advances through the Use of Human Pluripotent Stem Cell Models. Genes (Basel) 2023; 14:1864. [PMID: 37895213 PMCID: PMC10606441 DOI: 10.3390/genes14101864] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/11/2023] [Accepted: 09/16/2023] [Indexed: 10/29/2023] Open
Abstract
Cardiomyopathies (CMPs) represent a significant healthcare burden and are a major cause of heart failure leading to premature death. Several CMPs are now recognized to have a strong genetic basis, including arrhythmogenic cardiomyopathy (ACM), which predisposes patients to arrhythmic episodes. Variants in one of the five genes (PKP2, JUP, DSC2, DSG2, and DSP) encoding proteins of the desmosome are known to cause a subset of ACM, which we classify as desmosome-related ACM (dACM). Phenotypically, this disease may lead to sudden cardiac death in young athletes and, during late stages, is often accompanied by myocardial fibrofatty infiltrates. While the pathogenicity of the desmosome genes has been well established through animal studies and limited supplies of primary human cells, these systems have drawbacks that limit their utility and relevance to understanding human disease. Human induced pluripotent stem cells (hiPSCs) have emerged as a powerful tool for modeling ACM in vitro that can overcome these challenges, as they represent a reproducible and scalable source of cardiomyocytes (CMs) that recapitulate patient phenotypes. In this review, we provide an overview of dACM, summarize findings in other model systems linking desmosome proteins with this disease, and provide an up-to-date summary of the work that has been conducted in hiPSC-cardiomyocyte (hiPSC-CM) models of dACM. In the context of the hiPSC-CM model system, we highlight novel findings that have contributed to our understanding of disease and enumerate the limitations, prospects, and directions for research to consider towards future progress.
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Affiliation(s)
- Christianne J. Chua
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (C.J.C.); (J.M.-M.); (L.T.)
| | - Justin Morrissette-McAlmon
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (C.J.C.); (J.M.-M.); (L.T.)
| | - Leslie Tung
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (C.J.C.); (J.M.-M.); (L.T.)
| | - Kenneth R. Boheler
- Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; (C.J.C.); (J.M.-M.); (L.T.)
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Mingorance Álvarez E, Martínez Quintana R, Pérez Pico AM, Mayordomo R. Predictive Model of Nail Consistency Using Scanning Electron Microscopy with Energy-Dispersive X-Ray. BIOLOGY 2021; 10:biology10010053. [PMID: 33445794 PMCID: PMC7828269 DOI: 10.3390/biology10010053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/11/2021] [Indexed: 11/22/2022]
Abstract
Simple Summary Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) is a useful technique to analyse elemental composition in the nail plate. The dorsal, intermediate, and ventral layers are differentiated by the levels of the elements present in each layer. The level of calcium in the dorsal layer is the main predictive variable in calculating the predictive model of consistency. This model will provide further knowledge of the factors that determine nail consistency in individuals and help health professionals to better understand nail characteristics and objectively determine nail consistency. Abstract The nail plate is made up of tightly packed keratin-rich cells. Factors such as the special distribution of the intermediate filaments in each layer (dorsal, intermediate, and ventral), the relative thickness of the layers, and their chemical composition define the characteristics of each nail. The main objective of this study is to determine nail consistency by calculating a predictive model based on elemental composition analysis using scanning electron microscopy. Nail consistency was determined in 57 participants (29 women and 28 men) in two age groups (young people and adults). Elemental composition was analysed in each layer using scanning SEM-EDS, and nail plate thickness was measured by image analysis. A total of 12 elements were detected in nail plates, of which carbon, nitrogen, phosphorus, sulphur, and calcium showed significant differences between layers (p-values ≤ 0.01). The level of calcium in the dorsal layer was the main predictive variable in calculating the predictive model of consistency, with 75.4% correctly classified cases. Elemental analysis in each layer of the nail plate by SEM-EDS can be used to develop a predictive model of nail consistency that will help health professionals to objectively determine nail consistency.
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Affiliation(s)
- Esther Mingorance Álvarez
- Department of Anatomy and Cell Biology, University Center of Plasencia, University of Extremadura, Avda. Virgen del Puerto 2, 10600 Plasencia, Cáceres, Spain;
| | - Rodrigo Martínez Quintana
- Department of Mathematics, University Center of Plasencia, University of Extremadura, Avda. Virgen del Puerto 2, 10600 Plasencia, Cáceres, Spain;
| | - Ana Mª Pérez Pico
- Department of Nursing, University Center of Plasencia, University of Extremadura, Avda. Virgen del Puerto 2, 10600 Plasencia, Cáceres, Spain;
| | - Raquel Mayordomo
- Department of Anatomy and Cell Biology, University Center of Plasencia, University of Extremadura, Avda. Virgen del Puerto 2, 10600 Plasencia, Cáceres, Spain;
- Correspondence: ; Tel.: +34-636526498; Fax: +34-927425209
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Desmoglein1 Deficiency Is a Potential Cause of Cutaneous Eruptions Induced by Shuanghuanglian Injection. Molecules 2018; 23:molecules23061477. [PMID: 29921748 PMCID: PMC6099613 DOI: 10.3390/molecules23061477] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 06/13/2018] [Indexed: 12/15/2022] Open
Abstract
Cutaneous eruption is a common drug-adverse reaction, characterised by keratinocytes inflammation and apoptosis. Shuanghuanglian injeciton (SHLI) is a typical Chinese medicine injection, which is used to treat influenza. It has been reported that SHLI has the potential to induce cutaneous adverse eruptions. However, the mechanisms remain unclear. Since desmoglein 1 (DSG1) shows a crucial role in maintaining skin barrier function and cell susceptibility, we assume that DSG1 plays a critical role in the cutaneous eruptions induced by SHLI. In our study, retinoic acid (RA) was selected to downregulate the DSG1 expression, and lipopolysaccharide (LPS) was first used to identify the susceptibility of the DSG1-deficiency Hacat cells. Then, SHLI was administrated to normal or DSG1-deficient Hacat cells and mice. The inflammatory factors and apoptosis rate were evaluated by RT-PCR and flow cytometry. The skin pathological morphology was observed by hematoxylin and eosin (HE) staining. Our results show that treated only with SHLI could not cause IL-4 and TNF-α mRNA increases in normal Hacat cells. However, in the DSG1-deficient Hacat cells or mice, SHLI induced an extreme increase of IL-4 and TNF-α mRNA levels, as well as in the apoptosis rate. The skin tissue showed a local inflammatory cell infiltration when treated with SHIL in the DSG1-deficient mice. Thus, we concluded that DSG1 deficiency was a potential causation of SHLI induced eruptions. These results indicated that keratinocytes with DSG1 deficiency were likely to induce the cutaneous eruptions when stimulated with other medicines.
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Bokstad M, Sabanay H, Dahan I, Geiger B, Medalia O. Reconstructing adhesion structures in tissues by cryo-electron tomography of vitrified frozen sections. J Struct Biol 2011; 178:76-83. [PMID: 22085747 DOI: 10.1016/j.jsb.2011.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 10/27/2011] [Accepted: 10/30/2011] [Indexed: 01/15/2023]
Abstract
Cryo-electron tomography enables three-dimensional insights into the macromolecular architecture of cells in a close-to-life state. However, it is limited to thin specimens, <1.0 μm in thickness, typically restricted to the peripheral areas of intact eukaryotic cells. Analysis of tissue ultrastructure, on the other hand, requires physical sectioning approaches, preferably cryo-sectioning, following which electron tomography (ET) may be performed. Nevertheless, cryo-electron microscopy of vitrified sections is a demanding technique and typically cannot be used to examine thick sections, >80-100 nm, due to surface crevasses. Here, we explore the potential use of cryo-ET of vitrified frozen sections (VFSs) for imaging cell adhesions in chicken smooth muscle and mouse epithelial tissues. By investigating 300-400 nm thick sections, which are collected on the EM grid and re-vitrified, we resolved fine 3D structural details of the membrane-associated dense plaques and flanking caveoli in smooth muscle tissue, and desmosomal adhesions in stratified epithelium. Technically, this method offers a simple approach for reconstructing thick volumes of hydrated frozen sections.
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Affiliation(s)
- Melanie Bokstad
- Department of Life Sciences, Ben-Gurion University of the Negev, BeerSheva 84105, Israel
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Mutations in the desmoglein 1 gene in five Pakistani families with striate palmoplantar keratoderma. J Dermatol Sci 2009; 53:192-7. [PMID: 19157795 DOI: 10.1016/j.jdermsci.2008.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 11/09/2008] [Accepted: 11/13/2008] [Indexed: 11/24/2022]
Abstract
BACKGROUND Striate palmoplantar keratoderma (SPPK; OMIM #148700) is a rare autosomal dominant genodermatosis characterized by linear hyperkeratosis on the digits and hyperkeratosis on the palms and soles. SPPK is known to be caused by heterozygous mutations in either the desmoglein 1 (DSG1), desmoplakin (DSP), or keratin 1 (KRT1) genes. OBJECTIVE To define the molecular basis of SPPK in five Pakistani families showing a clear autosomal dominant inheritance pattern of SPPK. METHODS Based on previous reports of DSG1 mutations in SPPK, we performed direct sequencing of the DSG1 gene of all five families. RESULTS Mutation analysis resulted in the identification of one recurrent mutation (p.R26X) and four novel mutations (c.Ivs4-2A>G, c.515C>T, c.Ivs9-3C>G, and c.1399delA) in the DSG1 gene. Each mutation is predicted to cause haploinsufficiency of DSG1 protein. CONCLUSION The results of our study further underscore the significance of the desmoglein gene family in diseases of epidermal integrity.
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Barber AG, Wajid M, Columbo M, Lubetkin J, Christiano AM. Striate palmoplantar keratoderma resulting from a frameshift mutation in the desmoglein 1 gene. J Dermatol Sci 2006; 45:161-6. [PMID: 17194569 PMCID: PMC2914539 DOI: 10.1016/j.jdermsci.2006.11.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 11/10/2006] [Accepted: 11/14/2006] [Indexed: 10/23/2022]
Abstract
BACKGROUND Striate keratodermas (PPKS) are a group of rare autosomal dominant palmoplantar keratodermas, characterized by a thickening of the skin on the palms and soles. PPKS is characterized by hyperkeratosis extending along the length of each finger and on the palm of the hand, as well as by patches of hyperkeratosis on the soles. OBJECTIVE We report a four-generation Pakistani kindred in which 11 members were affected with PPKS. METHODS Based on previous reports of DSG1 mutations in PPKS, we performed direct DNA sequencing analysis. RESULTS Clinically, these patients presented with hyperkeratotic palms and with linear hyperkeratosis on the fingers. Additionally, focal hyperkeratosis was seen on the sole of the toes as well as the ball and heel of the foot. DNA sequencing analysis revealed a heterozygous G-to-T transversion in the 3' splice acceptor site of intron 11 of the DSG1 gene designated 1688 -1 G>T. We predict that this mutation will lead to the skipping of exon 12 which is out of frame (134nt), subsequent degradation of the mutant mRNA by non-sense mediated RNA decay, and haploinsufficiency for DSG1. CONCLUSION We report a novel splice site mutation in the DSG1 gene in PPKS, which further underscores the significance of the desmoglein gene family in diseases of epidermal integrity.
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Affiliation(s)
- Alison G. Barber
- Department of Genetics & Development, Columbia University, New York, NY USA
| | - Muhammad Wajid
- Department of Dermatology, Columbia University, New York, NY USA
| | - Morgana Columbo
- Department of Dermatology, Columbia University, New York, NY USA
| | - Jillian Lubetkin
- Department of Dermatology, Columbia University, New York, NY USA
| | - Angela M. Christiano
- Department of Genetics & Development, Columbia University, New York, NY USA
- Department of Dermatology, Columbia University, New York, NY USA
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Badeloe S, van Geel M, van Steensel MAM, Bastida J, Ferrando J, Steijlen PM, Frank J, Poblete-Gutiérrez P. Diffuse and segmental variants of cutaneous leiomyomatosis: novel mutations in the fumarate hydratase gene and review of the literature. Exp Dermatol 2006; 15:735-41. [PMID: 16881969 DOI: 10.1111/j.1600-0625.2006.00470.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Multiple cutaneous and uterine leiomyomatosis (MCUL; OMIM 150800) is an autosomal dominantly inherited disease characterized by leiomyomas of the skin and uterine leiomyomas. Recently, association of MCUL with different forms of renal cancer has been described. This syndrome is referred to as hereditary leiomyomatosis and renal cell cancer (OMIM 605839). Both disorders result from heterozygous germline mutations in the fumarate hydratase (FH) gene that may function as a tumor suppressor. Interestingly, cutaneous leiomyomas do not only manifest in a diffuse and symmetric fashion. Rather frequently, a segmental or band-like manifestation pattern can be observed, usually following the lines of Blaschko. Here, we sought to elucidate the molecular basis of diffuse and segmental cutaneous leiomyomatosis in six unrelated Dutch and Spanish patients and their families. We identified six novel FH mutations, including one missense and one nonsense mutation, two deletions and two splice-site mutations. The segmental phenotype that was observed in various patients with FH mutations most likely reflects a type 2 segmental manifestation of cutaneous leiomyomatosis as previously also described for other autosomal dominantly inherited skin diseases. The results presented here extend the current data on the molecular basis of familial cutaneous leiomyomatosis and comprise, to the best of our knowledge, the first genetic study in Dutch and Spanish patients with this disorder. In addition, we review the clinical and molecular aspects of the disease.
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Affiliation(s)
- Sadhanna Badeloe
- Department of Dermatology, University Hospital Maastricht, Maastricht, The Netherlands
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Yiu WH, Poon JWM, Tsui SKW, Fung KP, Waye MMY. Cloning and characterization of a novel endoplasmic reticulum localized G-patch domain protein, IER3IP1. Gene 2004; 337:37-44. [PMID: 15276200 DOI: 10.1016/j.gene.2004.04.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Revised: 04/04/2004] [Accepted: 04/26/2004] [Indexed: 11/28/2022]
Abstract
The endoplasmic reticulum (ER) is the site of protein synthesis, folding, post-translational modifications and export. The ER membrane and its lumen contain various chaperones and enzymes that are involved in every aspect of the ER function. In this report, we identified a novel endoplasmic reticulum protein (immediate early response 3 interacting protein 1, IER3IP1) during the large-scale partial sequencing of a liver cDNA library. The full-length 1304 bp IER3IP1 cDNA has a predicted open reading frame (ORF), which encodes an 82 amino-acid protein possessing a G-patch domain. This domain is found in several RNA associated proteins and has been suggested to be involved in RNA binding. IER3IP1 gene was mapped to the chromosome 18q12 by radiation hybrid analysis. In northern blot hybridization, it was shown that IER3IP1 gene has a high expression in heart, skeletal muscle and kidney, a moderate expression in liver and brain and a low expression in placenta, lung and peripheral blood leukocyte. With the presence of transmembrane domain at the C-terminal, the translated IER3IP1 protein was localized to endoplasmic reticulum of HepG2 cells and was confirmed by co-localization with ER specific marker.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Binding Sites/genetics
- Blotting, Northern
- Carrier Proteins/genetics
- Cell Line, Tumor
- Chromosomes, Human, Pair 18/genetics
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- Endoplasmic Reticulum/metabolism
- Female
- Gene Expression Profiling
- Green Fluorescent Proteins
- Humans
- Luminescent Proteins/genetics
- Luminescent Proteins/metabolism
- Membrane Proteins/genetics
- Microscopy, Fluorescence
- Molecular Sequence Data
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Radiation Hybrid Mapping
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- Wai Han Yiu
- Department of Biochemistry, The Chinese University of Hong Kong, Mong Man Wai Building, Shatin, N.T., Hong Kong, China
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Kljuic A, Gilead L, Martinez-Mir A, Frank J, Christiano AM, Zlotogorski A. A nonsense mutation in the desmoglein 1 gene underlies striate keratoderma. Exp Dermatol 2003; 12:523-7. [PMID: 12930313 DOI: 10.1034/j.1600-0625.2003.00017.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Striate keratodermas (PPKS) (OMIM 148700) are a rare group of autosomal dominant genodermatoses characterized by palmoplantar keratoderma typified by streaking hyperkeratosis along each finger and extending onto the palm of the hand. We report a four-generation kindred originating from Iran-Syria in which three members were affected with PPKS. Clinically, these patients present with hyperkeratotic palms and plantar plaques. Direct DNA sequencing analysis revealed a heterozygous C-to-A transversion at nt 395 of the DSG1 gene. This mutation converted a serine residue (TCA) in exon 5 to a nonsense mutation (TAA) designated S132X. The mutation identified in this study is a novel mutation in the DSG1 gene and extends the body of evidence implicating the desmoglein gene family in the pathogenesis of human skin disorders.
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Affiliation(s)
- Ana Kljuic
- Department of Genetics and Development, Columbia University, New York, NY, USA
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Whittock NV. Genomic Sequence Analysis of the Mouse Desmoglein Cluster Reveals Evidence for Six Distinct Genes: Characterization of Mouse DSG4, DSG5, and DSG6. J Invest Dermatol 2003. [DOI: 10.1038/jid.2003.10] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
Desmosomes are essential adhesion structures in most epithelia that link the intermediate filament network of one cell to its neighbor, thereby forming a strong bond. The molecular components of desmosomes belong to the cadherin superfamily, the plakin family, and the armadillo repeat protein family. The desmosomal cadherins are calcium-dependent transmembrane adhesion molecules and comprise the desmogleins and desmocollins. To date, three human desmoglein isoforms have been characterized, namely desmogleins 1, 2, and 3 that are expressed in a tissue- and differentiation-specific manner. Here we have identified and characterized, at the genetic level, a novel human desmoglein cDNA sharing homology with desmogleins 1, 2, 3 and we name this desmoglein 4. The human desmoglein 4 cDNA (3.6 kb) contains an open reading frame of 3120 bp that encodes a precursor protein of 1040 amino acids. The predicted mature protein comprises 991 amino acids with a molecular weight of 107822 Da at pI 4.38. Human desmoglein 4 shares 41% identity with human desmoglein 1, 37% with human desmoglein 2, and 50% with human desmoglein 3. Analysis of the exon/intron organization of the human desmoglein 4 gene (DSG4) demonstrates that it is composed of 16 exons spanning approximately 37 kb of 18q12 and is situated between DSG1 and DSG3. We have demonstrated using RT-PCR on multiple tissue cDNA samples that desmoglein 4 has very specific tissue expression in salivary gland, testis, prostate, and skin.
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Affiliation(s)
- Neil V Whittock
- Institute of Biomedical and Clinical Science, Peninsula Medical School, Exeter, United Kingdom.
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Affiliation(s)
- Ken Ishii
- Keio University School of Medicine, Tokyo, Japan
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Abstract
The mouse desmogleins are members of the desmosomal cadherin superfamily, and are critical structural components of the desmosome. The genes encoding mouse desmogleins are tightly clustered within 600 kb of chromosome 18, within a desmosomal cadherin gene family also containing the three desmocollin genes. In this study, we have characterized a novel mouse desmoglein gene, highly homologous to both mouse and human Dsg1, designated desmoglein 1 gamma (Dsg1c). Dsg1 gamma shares 83% amino acid identity to the previously described mouse Dsg1, now designated as Dsg1 alpha, and 32% and 40% identity to mouse Dsg2 and 3, respectively. The Dsg1 gamma gene maps within the desmosomal gene cluster, between Dsc1 and Dsg1 alpha. Comparison of its exon-intron structure revealed a high level of evolutionary conservation with related family members. In contrast to Dsg1 alpha and Dsg3 whose expression is largely restricted to the skin, Dsg1 gamma is also expressed in the brain, skeletal muscle, and liver, among other tissues, and is thus more similar to Dsg2 in its tissue distribution. Interestingly, an orthologous Dsg1 gamma was not found in the human genome, suggesting that the desmosomal cadherin gene cluster contracted during mammalian evolution.
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Affiliation(s)
- A Kljuic
- Department of Genetics and Development, Columbia University, New York, NY 10032, USA
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Mahoney MG, Simpson A, Aho S, Uitto J, Pulkkinen L. Interspecies conservation and differential expression of mouse desmoglein gene family. Exp Dermatol 2002; 11:115-25. [PMID: 11994138 DOI: 10.1034/j.1600-0625.2002.110203.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Epithelial cell adhesion is mediated by intercellular junctions, called desmosomes. Desmogleins (Dsg; Dsg1, Dsg2 and Dsg3) are calcium-dependent transmembrane adhesion components of the desmosomes. While Dsg1 and Dsg3 are mainly restricted to stratified squamous epithelia, Dsg2 is expressed in essentially all desmosome-containing epithelia. In the epidermis, Dsg2 and Dsg3 are expressed in the basal keratinocytes while Dsg1 is expressed throughout the upper differentiating cell layers. To date, in mouse, only Dsg3 has been characterized by molecular cloning. In this study, we have cloned and characterized the mouse Dsg1 and Dsg2 genes. The full-length mouse Dsg1 cDNA (5.5 kb) contains an open reading frame (ORF) of 3171 bp encoding a precursor protein of 1057 amino acids. The Dsg2 cDNA (6.3 kb) has an ORF of 3366 bp coding for a precursor protein of 1122 amino acids. Mouse Dsg2 protein shares 76% identity with human DSG2 but only 26% and 33% identity with mouse Dsg1 and Dsg3, respectively. Analysis of intron/exon organization of the desmoglein genes revealed significant conservation. However, the mRNA expression patterns of these desmogleins during mouse embryonic development and in various adult tissues are variable. While Dsg2 and Dsg3 are expressed in all developmental stages, Dsg1 expression is delayed until day 15 of mouse embryos. In adult mouse tissues, Dsg2 is widely expressed while the expression of Dsg1 and Dsg3 is restricted to select tissues. In summary, while desmogleins share high homology at both the gene and protein level, their expression is spatially and temporally regulated, potentially contributing to their significant role in cell-cell adhesion during development.
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Affiliation(s)
- My G Mahoney
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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