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Mao L, Wang Y, An L, Zeng B, Wang Y, Frishman D, Liu M, Chen Y, Tang W, Xu H. Molecular Mechanisms and Clinical Phenotypes of GJB2 Missense Variants. Biology 2023; 12:biology12040505. [PMID: 37106706 PMCID: PMC10135792 DOI: 10.3390/biology12040505] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 03/29/2023]
Abstract
The GJB2 gene is the most common gene responsible for hearing loss (HL) worldwide, and missense variants are the most abundant type. GJB2 pathogenic missense variants cause nonsyndromic HL (autosomal recessive and dominant) and syndromic HL combined with skin diseases. However, the mechanism by which these different missense variants cause the different phenotypes is unknown. Over 2/3 of the GJB2 missense variants have yet to be functionally studied and are currently classified as variants of uncertain significance (VUS). Based on these functionally determined missense variants, we reviewed the clinical phenotypes and investigated the molecular mechanisms that affected hemichannel and gap junction functions, including connexin biosynthesis, trafficking, oligomerization into connexons, permeability, and interactions between other coexpressed connexins. We predict that all possible GJB2 missense variants will be described in the future by deep mutational scanning technology and optimizing computational models. Therefore, the mechanisms by which different missense variants cause different phenotypes will be fully elucidated.
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Affiliation(s)
- Lu Mao
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yueqiang Wang
- Basecare Medical Device Co., Ltd., Suzhou 215000, China
| | - Lei An
- Translational Medicine Center, Huaihe Hospital of Henan University, Kaifeng 475000, China
| | - Beiping Zeng
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yanyan Wang
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
| | - Dmitrij Frishman
- Wissenschaftszentrum Weihenstephan, Technische Universitaet Muenchen, Am Staudengarten 2, 85354 Freising, Germany
| | - Mengli Liu
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Yanyu Chen
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
| | - Wenxue Tang
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
| | - Hongen Xu
- Precision Medicine Center, Academy of Medical Science, Zhengzhou University, Zhengzhou 450052, China
- The Research and Application Center of Precision Medicine, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou 450014, China
- Correspondence:
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Chen Y, Wang Z, Song Y, Chen N, Guo J, Liu W, Guo K, Ling X, Zhang L. 4-octyl itaconate improves the viability of D66H cells by regulating the KEAP1-NRF2-GCLC/HO-1 pathway. J Cell Mol Med 2023; 27:962-975. [PMID: 36916028 PMCID: PMC10064036 DOI: 10.1111/jcmm.17708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 02/18/2023] [Accepted: 02/22/2023] [Indexed: 03/16/2023] Open
Abstract
As a novel nuclear factor E2-related factor 2 (NRF2) activator, the itaconate has shown significant therapeutic potential for oxidative stress diseases. However, its role in Vohwinkel syndrome in relation to the gap junction protein beta 2 (GJB2) mutation is still unclear. This study aimed at investigating the effect of 4-octyl itaconate (OI) on HaCaT and D66H cells and clarify its potential mechanism in vitro. The optimal concentration and treatment time of OI on HaCaT cells and D66H cells were determined by CCK-8 and LDH experiments. The effect of OI on cell proliferation was detected by EdU staining and FACS analysis of PI, while the apoptosis was evaluated by TUNEL staining and FACS analysis of Annexin V. The ROS staining was performed, and the levels of SOD, MDA, GSH and GSH/GSSG were detected to evaluate the effect of OI on oxidative damage induced by D66H-type mutation. CO-IP, Western blot, immunofluorescence and qPCR analyses were employed to detect the activation of KEAP1-NRF2-GCLC/HO-1 pathway by OI. Finally, sh-NRF2 was used to confirm the activation of this pathway by OI. Results showed that OI could improve the cell viability decreased by GJB2 gene mutation by regulating the balance between cell growth and apoptosis induced by oxidative damage. Furthermore, this alleviation process was regulated by the KEAP1-NRF2-HO-1/GCLC pathway. In conclusion, OI could improve the viability of HaCaT and D66H cells via regulating the KEAP1-NRF2-GCLC/HO-1 pathway, which provided a wide spectrum of potential targets for effective therapeutic treatments of Vohwinkel syndrome in the clinic.
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Affiliation(s)
- Yanrui Chen
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Zhenying Wang
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yali Song
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Nan Chen
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Jing Guo
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Wenmin Liu
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Keying Guo
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Xia Ling
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Li Zhang
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.,Department of Dermatology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
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3
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Ling X, Dong S, Zhang L. Low dose TGF-β1 can improve vohwinkel syndrome by promoting the proliferation of keratinocytes. Acta Histochem 2023; 125:152010. [PMID: 36738515 DOI: 10.1016/j.acthis.2023.152010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 01/19/2023] [Accepted: 01/27/2023] [Indexed: 02/05/2023]
Abstract
Vohwinkel syndrome (VS) is a very rare autosomal dominant disorder that can cause disability and deformity in severe cases. Mutations of the LOR (loricrin) and GJB2 (Cx26) genes have been found in VS so far. Many studies have indicated that the differentiation and growth of epidermal keratinocytes are regulated by mutant Cx26, and it may explain the pathogenesis of VS. It has been found that transforming growth factor β1 (TGF-β1) expression was lower in G130V (OE1) and D66H (OE2) mutant keratinocytes in the VS model with GJB2 mutation as compared to normal keratinocytes (NC). TGF-β is a cytokine involved in the regulation of processes like cell proliferation and differentiation in different types of cells. At present, many in vitro studies focus on TGF- β 1 inhibition of keratinocyte growth.However, the relationship between TGF-β1 and VS remains unknown. This study aimed at elucidating the role and potential pathogenic mechanism of TGF-β in VS. The results indicated that the down-regulation expression of TGF-β1 in VS was linked to cell proliferation inhibition through p-Smad3/c-myc. In contrast, low-dose TGF-β1 treatment of VS keratinocytes can improve their proliferation inhibition and up-regulate the expression Cyclin D1. This suggests that low doses of TGF-β1 can improve the proliferation of VS and provide new insights into its treatment.
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Affiliation(s)
- Xia Ling
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan 250021, Shandong, China; Shandong First Medical University, Jinan 250117, Shandong, China
| | - Shujing Dong
- Department of Dermatology, Affiliated Hospital of Shandong University of traditional Chinese Medicine, Jinan 250012, Shandong, China
| | - Li Zhang
- Department of Dermatology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan 250021, Shandong, China.
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Baaniya B, Agrawal S. Exploring Pseudoainhum in Camisa syndrome. Clin Case Rep 2021; 9:e04995. [PMID: 34721860 PMCID: PMC8538013 DOI: 10.1002/ccr3.4995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 10/12/2021] [Indexed: 11/23/2022] Open
Abstract
Immediate treatment of Camisa syndrome with systemic retinoids or surgery helps to prevent loss of digits. Here, we report a case of Camisa syndrome with pseudoainhum in the fifth toe leading to amputation as timely treatment was not sought.
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Affiliation(s)
- Bibisha Baaniya
- Junior ResidentB.P. Koirala Institute of Health SciencesDharanNepal
| | - Sudha Agrawal
- Department of Dermatology and VenerologyB.P. Koirala Institute of Health SciencesDharanNepal
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King DR, Sedovy MW, Leng X, Xue J, Lamouille S, Koval M, Isakson BE, Johnstone SR. Mechanisms of Connexin Regulating Peptides. Int J Mol Sci 2021; 22:ijms221910186. [PMID: 34638526 PMCID: PMC8507914 DOI: 10.3390/ijms221910186] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/16/2021] [Accepted: 09/17/2021] [Indexed: 12/22/2022] Open
Abstract
Gap junctions (GJ) and connexins play integral roles in cellular physiology and have been found to be involved in multiple pathophysiological states from cancer to cardiovascular disease. Studies over the last 60 years have demonstrated the utility of altering GJ signaling pathways in experimental models, which has led to them being attractive targets for therapeutic intervention. A number of different mechanisms have been proposed to regulate GJ signaling, including channel blocking, enhancing channel open state, and disrupting protein-protein interactions. The primary mechanism for this has been through the design of numerous peptides as therapeutics, that are either currently in early development or are in various stages of clinical trials. Despite over 25 years of research into connexin targeting peptides, the overall mechanisms of action are still poorly understood. In this overview, we discuss published connexin targeting peptides, their reported mechanisms of action, and the potential for these molecules in the treatment of disease.
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Affiliation(s)
- D. Ryan King
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
| | - Meghan W. Sedovy
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Translational Biology, Medicine, and Health Graduate Program, Virginia Tech, Blacksburg, VA 24061, USA
| | - Xinyan Leng
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
| | - Jianxiang Xue
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (J.X.); (B.E.I.)
| | - Samy Lamouille
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA 24016, USA
| | - Michael Koval
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA;
| | - Brant E. Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA; (J.X.); (B.E.I.)
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Scott R. Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion School of Medicine, Virginia Tech, Roanoke, VA 24016, USA; (D.R.K.); (M.W.S.); (X.L.); (S.L.)
- Center for Vascular and Heart Research, Virginia Tech, Roanoke, VA 24016, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
- Correspondence:
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Peracchia C. Gap Junction Channelopathies and Calmodulinopathies. Do Disease-Causing Calmodulin Mutants Affect Direct Cell-Cell Communication? Int J Mol Sci 2021; 22:9169. [PMID: 34502077 DOI: 10.3390/ijms22179169] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/19/2021] [Accepted: 08/21/2021] [Indexed: 11/24/2022] Open
Abstract
The cloning of connexins cDNA opened the way to the field of gap junction channelopathies. Thus far, at least 35 genetic diseases, resulting from mutations of 11 different connexin genes, are known to cause numerous structural and functional defects in the central and peripheral nervous system as well as in the heart, skin, eyes, teeth, ears, bone, hair, nails and lymphatic system. While all of these diseases are due to connexin mutations, minimal attention has been paid to the potential diseases of cell–cell communication caused by mutations of Cx-associated molecules. An important Cx accessory protein is calmodulin (CaM), which is the major regulator of gap junction channel gating and a molecule relevant to gap junction formation. Recently, diseases caused by CaM mutations (calmodulinopathies) have been identified, but thus far calmodulinopathy studies have not considered the potential effect of CaM mutations on gap junction function. The major goal of this review is to raise awareness on the likely role of CaM mutations in defects of gap junction mediated cell communication. Our studies have demonstrated that certain CaM mutants affect gap junction channel gating or expression, so it would not be surprising to learn that CaM mutations known to cause diseases also affect cell communication mediated by gap junction channels.
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Yoneda K, Kubo A, Nomura T, Ishida-Yamamoto A, Suga Y, Akiyama M, Kanazawa N, Hashimoto T. Japanese guidelines for the management of palmoplantar keratoderma. J Dermatol 2021; 48:e353-e367. [PMID: 34121213 DOI: 10.1111/1346-8138.15850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 11/27/2022]
Abstract
Palmoplantar keratoderma (PPK) is a collective term for keratinizing disorders in which the main clinical symptom is hyperkeratosis on the palms and soles. To establish the first Japanese guidelines approved by the Japanese Dermatological Association for the management of PPKs, the Committee for the Management of PPKs was founded as part of the Study Group for Rare Intractable Diseases. These guidelines aim to provide current information for the management of PPKs in Japan. Based on evidence, they summarize the clinical manifestations, pathophysiologies, diagnostic criteria, disease severity determination criteria, treatment, and treatment recommendations. Because of the rarity of PPKs, there are only few clinical studies with a high degree of evidence. Therefore, several parts of these guidelines were established based on the opinions of the committee. To further optimize the guidelines, periodic revision in line with new evidence is necessary.
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Affiliation(s)
- Kozo Yoneda
- Department of Clinical Pharmacology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Japan
| | - Akiharu Kubo
- Department of Dermatology, Keio University Graduate School of Medicine, Tokyo, Japan
| | | | | | - Yasushi Suga
- Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Japan
| | - Masashi Akiyama
- Department of Dermatology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Nobuo Kanazawa
- Department of Dermatology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Takashi Hashimoto
- Department of Dermatology, Osaka City University Graduate School of Medicine, Osaka, Japan
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Rovere G, Stramazzo L, Cioffi A, Galvano N, Pavan D, Restuccia G, D'Arienzo A, Capanna R, Maccauro G, D'Arienzo M, Camarda L. What's the resolutive surgery for pseudo-ainhum in Vohwinkel syndrome? A case report and review of the literature. Orthop Rev (Pavia) 2021; 12:8868. [PMID: 33633820 PMCID: PMC7883105 DOI: 10.4081/or.2020.8868] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/22/2020] [Indexed: 11/22/2022] Open
Abstract
Vohwinkel Syndrome, also known as Keratoderma Hereditarium Mutilans, is an extremely rare dominant autosomal keratosis. It typically presents with “starfish” keratoses on the knuckles, palmoplantar keratoderma (PPK), hearing impairment and mutilating digital constriction bands (pseudoainhum) that cause strangulation, often leading to autoamputation of the affected digit. Both medical and surgical treatment haven’t shown to date consistent results, in the treatment of pseudoainhum. In this study we present the case of a woman with Vohwinkel syndrome who showed constriction bands causing ischemic changes of the 5th digit of the right hand for which she was treated with surgery. We also present a review of the literature for the management of this disease.
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Affiliation(s)
- Giuseppe Rovere
- Department of Orthopaedics and Traumatology, Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore, Rome
| | - Leonardo Stramazzo
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
| | - Alessio Cioffi
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
| | - Nicolò Galvano
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
| | - Davide Pavan
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
| | | | | | - Rodolfo Capanna
- Department of Orthopaedic Surgery, University of Pisa, Italy
| | - Giulio Maccauro
- Department of Orthopaedics and Traumatology, Fondazione Policlinico Universitario A. Gemelli IRCCS - Università Cattolica del Sacro Cuore, Rome
| | - Michele D'Arienzo
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
| | - Lawrence Camarda
- Department of Orthopaedic Surgery (DICHIRONS), Università degli Studi di Palermo
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Garcia-Vega L, O’Shaughnessy EM, Albuloushi A, Martin PE. Connexins and the Epithelial Tissue Barrier: A Focus on Connexin 26. Biology (Basel) 2021; 10:biology10010059. [PMID: 33466954 PMCID: PMC7829877 DOI: 10.3390/biology10010059] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/11/2021] [Accepted: 01/12/2021] [Indexed: 12/15/2022]
Abstract
Simple Summary Tissues that face the external environment are known as ‘epithelial tissue’ and form barriers between different body compartments. This includes the outer layer of the skin, linings of the intestine and airways that project into the lumen connecting with the external environment, and the cornea of the eye. These tissues do not have a direct blood supply and are dependent on exchange of regulatory molecules between cells to ensure co-ordination of tissue events. Proteins known as connexins form channels linking cells directly and permit exchange of small regulatory signals. A range of environmental stimuli can dysregulate the level of connexin proteins and or protein function within the epithelia, leading to pathologies including non-healing wounds. Mutations in these proteins are linked with hearing loss, skin and eye disorders of differing severity. As such, connexins emerge as prime therapeutic targets with several agents currently in clinical trials. This review outlines the role of connexins in epithelial tissue and how their dysregulation contributes to pathological pathways. Abstract Epithelial tissue responds rapidly to environmental triggers and is constantly renewed. This tissue is also highly accessible for therapeutic targeting. This review highlights the role of connexin mediated communication in avascular epithelial tissue. These proteins form communication conduits with the extracellular space (hemichannels) and between neighboring cells (gap junctions). Regulated exchange of small metabolites less than 1kDa aide the co-ordination of cellular activities and in spatial communication compartments segregating tissue networks. Dysregulation of connexin expression and function has profound impact on physiological processes in epithelial tissue including wound healing. Connexin 26, one of the smallest connexins, is expressed in diverse epithelial tissue and mutations in this protein are associated with hearing loss, skin and eye conditions of differing severity. The functional consequences of dysregulated connexin activity is discussed and the development of connexin targeted therapeutic strategies highlighted.
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Maslova EA, Orishchenko KE, Posukh OL. Functional Evaluation of a Rare Variant c.516G>C (p.Trp172Cys) in the GJB2 (Connexin 26) Gene Associated with Nonsyndromic Hearing Loss. Biomolecules 2021; 11:61. [PMID: 33466560 PMCID: PMC7824951 DOI: 10.3390/biom11010061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/03/2021] [Accepted: 01/04/2021] [Indexed: 01/05/2023] Open
Abstract
Mutations in the GJB2 gene encoding transmembrane protein connexin 26 (Cx26) are the most common cause for hearing loss worldwide. Cx26 plays a crucial role in the ionic and metabolic homeostasis in the inner ear, indispensable for normal hearing process. Different pathogenic mutations in the GJB2 gene can affect all stages of the Cx26 life cycle and result in nonsyndromic autosomal recessive (DFNB1) or dominant (DFNA3) deafness and syndromes associating hearing loss with skin disorders. This study aims to elucidate the functional consequences of a rare GJB2 variant c.516G>C (p.Trp172Cys) found with high frequency in deaf patients from indigenous populations of Southern Siberia (Russia). The substitution c.516G>C leads to the replacement of tryptophan at a conserved amino acid position 172 with cysteine (p.Trp172Cys) in the second extracellular loop of Cx26 protein. We analyzed the subcellular localization of mutant Cx26-p.Trp172Cys protein by immunocytochemistry and the hemichannels permeability by dye loading assay. The GJB2 knockout HeLa cell line has been generated using CRISPR/Cas9 genome editing tool. Subsequently, the HeLa transgenic cell lines stably expressing different GJB2 variants (wild type and mutations associated with hearing loss) were established based on knockout cells and used for comparative functional analysis. The impaired trafficking of mutant Cx26-p.Trp172Cys protein to the plasma membrane and reduced hemichannels permeability support the pathogenic effect of the c.516G>C (p.Trp172Cys) variant and its association with nonsyndromic hearing loss. Our data contribute to a better understanding of the role of mutations in the second extracellular loop of Cx26 protein in pathogenesis of deafness.
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Affiliation(s)
- Ekaterina A. Maslova
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia; (E.A.M.); (K.E.O.)
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Konstantin E. Orishchenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia; (E.A.M.); (K.E.O.)
- Novosibirsk State University, Novosibirsk 630090, Russia
| | - Olga L. Posukh
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk 630090, Russia; (E.A.M.); (K.E.O.)
- Novosibirsk State University, Novosibirsk 630090, Russia
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11
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Lee TL, Lin PH, Chen PL, Hong JB, Wu CC. Hereditary Hearing Impairment with Cutaneous Abnormalities. Genes (Basel) 2020; 12:43. [PMID: 33396879 PMCID: PMC7823799 DOI: 10.3390/genes12010043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/25/2020] [Accepted: 12/26/2020] [Indexed: 12/15/2022] Open
Abstract
Syndromic hereditary hearing impairment (HHI) is a clinically and etiologically diverse condition that has a profound influence on affected individuals and their families. As cutaneous findings are more apparent than hearing-related symptoms to clinicians and, more importantly, to caregivers of affected infants and young individuals, establishing a correlation map of skin manifestations and their underlying genetic causes is key to early identification and diagnosis of syndromic HHI. In this article, we performed a comprehensive PubMed database search on syndromic HHI with cutaneous abnormalities, and reviewed a total of 260 relevant publications. Our in-depth analyses revealed that the cutaneous manifestations associated with HHI could be classified into three categories: pigment, hyperkeratosis/nail, and connective tissue disorders, with each category involving distinct molecular pathogenesis mechanisms. This outline could help clinicians and researchers build a clear atlas regarding the phenotypic features and pathogenetic mechanisms of syndromic HHI with cutaneous abnormalities, and facilitate clinical and molecular diagnoses of these conditions.
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Affiliation(s)
- Tung-Lin Lee
- Department of Medical Education, National Taiwan University Hospital, Taipei City 100, Taiwan;
| | - Pei-Hsuan Lin
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
| | - Pei-Lung Chen
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Internal Medicine, National Taiwan University Hospital, Taipei 10041, Taiwan
| | - Jin-Bon Hong
- Graduate Institute of Medical Genomics and Proteomics, National Taiwan University College of Medicine, Taipei City 100, Taiwan
- Department of Dermatology, National Taiwan University Hospital, Taipei City 100, Taiwan
| | - Chen-Chi Wu
- Department of Otolaryngology, National Taiwan University Hospital, Taipei 11556, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei City 100, Taiwan;
- Department of Medical Genetics, National Taiwan University Hospital, Taipei 10041, Taiwan
- Department of Medical Research, National Taiwan University Biomedical Park Hospital, Hsinchu City 300, Taiwan
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12
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Ikeda K, Takeichi T, Ito Y, Kawakami Y, Nakagawa Y, Naito S, Yamasaki O, Akiyama M, Morizane S. Classical Vohwinkel syndrome with heterozygous p.Asp66His mutation in
GJB2
gene: Second Asian case. J Dermatol 2020; 47:e352-e354. [DOI: 10.1111/1346-8138.15513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Kenta Ikeda
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
| | - Takuya Takeichi
- Department of Dermatology Nagoya University Graduate School of Medicine Nagoya Japan
| | - Yasutoshi Ito
- Department of Dermatology Nagoya University Graduate School of Medicine Nagoya Japan
| | - Yoshio Kawakami
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
| | - Yuki Nakagawa
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
| | - Seiko Naito
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
| | - Osamu Yamasaki
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
| | - Masashi Akiyama
- Department of Dermatology Nagoya University Graduate School of Medicine Nagoya Japan
| | - Shin Morizane
- Department of Dermatology Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Okayama Japan
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13
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Cocozzelli AG, White TW. Connexin 43 Mutations Lead to Increased Hemichannel Functionality in Skin Disease. Int J Mol Sci 2019; 20:ijms20246186. [PMID: 31817921 PMCID: PMC6940829 DOI: 10.3390/ijms20246186] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/29/2019] [Accepted: 12/04/2019] [Indexed: 12/22/2022] Open
Abstract
Gap junctional channels are specialized components of the cellular membrane that allow the intercellular passage of small metabolites, ions, and second messengers to maintain homeostasis. They are comprised of members of the connexin gene family that encode a wide array of proteins that are expressed in nearly every tissue type. Cx43 is perceived to be the most broadly expressed connexin in humans, with several genetic skin diseases being linked to Cx43 mutations specifically. These mutations, in large, produce a gain of functional hemichannels that contribute to the phenotypes of Erythrokeratoderma Variabilis et Progressiva (EKVP), Palmoplantar Keratodemra Congenital Alopecia-1 (PPKCA1), and others that produce large conductance and increased permselectivity in otherwise quiescent structures. Gaining functional hemichannels can have adverse effects in the skin, inducing apoptosis via Ca2+ overload or increased ATP permeability. Here, we review the link between Cx43 and skin disease. We aim to provide insight into the mechanisms regulating the normal and pathophysiological gating of these essential proteins, as well as address current therapeutic strategies. We also demonstrate that transient transfection of neuro-2a (N2a) cells with mutant Cx43 cDNA resulted in increased hemichannel activity compared to wild-type Cx43 and untransfected cells, which is consistent with other studies in the current literature.
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14
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Stylianaki EA, Karpouzis A, Tripsianis G, Veletza S. Assessment of Gap Junction Protein Beta-2 rs3751385 Gene Polymorphism in Psoriasis Vulgaris. J Clin Med Res 2019; 11:642-650. [PMID: 31523338 PMCID: PMC6731047 DOI: 10.14740/jocmr3845] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 06/25/2019] [Indexed: 02/05/2023] Open
Abstract
Background Gap junction protein beta 2 (GJB2) upregulation in psoriasis transcriptome analysis as well as connexin 26 (Cx26, encoded by GJB2) expression upregulation in psoriatic plaques has already been substantiated. GJB2 rs72474224 and rs3751385 have been correlated with psoriasis vulgaris incidence in Chinese populations. Here we study the effect of rs3751385 in patients suffering from psoriasis vulgaris in a Caucasian Greek population at the prefecture of Thrace in Northern Greece. Methods One hundred and seventy-three (111 males and 62 females) psoriatic patients (108 were of early-onset psoriasis) and 171 matched controls were included in the study. Genomic DNA was extracted from peripheral blood leukocytes and genotyping was carried out by polymerase chain reaction-restriction-fragment length polymorphism (PCR-RFLP). Results A statistically significant lower frequency of C/T genotype in late-onset male psoriasis vulgaris (P = 0.029) as well as of T allele in female early-onset psoriasis vulgaris (P = 0.049) were ascertained. Conclusions On condition that all other genetic or environmental factors remain stable, the existence and possible interaction between GJB2 rs3751385 C and T alleles in male psoriatic patients may be considered as protective gene component against late-onset psoriasis appearance, while presence of the T allele in female might block the histogenetic mechanisms of early-onset psoriasis lesions.
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Affiliation(s)
- Elli-Anna Stylianaki
- Department of Biology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Anthony Karpouzis
- Department of Dermatology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Gregory Tripsianis
- Department of Medical Statistics, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
| | - Stavroula Veletza
- Department of Biology, Faculty of Medicine, Democritus University of Thrace, Alexandroupolis, Greece
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15
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Abstract
Connexin 26 and connexin 30 are the prevailing isoforms in the epithelial and connective tissue gap junction systems of the developing and mature cochlea. The most frequently encountered variants of the genes that encode these connexins, which are transcriptionally coregulated, determine complete loss of protein function and are the predominant cause of prelingual hereditary deafness. Reducing connexin 26 expression by Cre/loxP recombination in the inner ear of adult mice results in a decreased endocochlear potential, increased hearing thresholds, and loss of >90% of outer hair cells, indicating that this connexin is essential for maintenance of cochlear function. In the developing cochlea, connexins are necessary for intercellular calcium signaling activity. Ribbon synapses and basolateral membrane currents fail to mature in inner hair cells of mice that are born with reduced connexin expression, even though hair cells do not express any connexin. In contrast, pannexin 1, an alternative mediator of intercellular signaling, is dispensable for hearing acquisition and auditory function.
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16
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Xie MX, Yang WP, Luo HJ, Ismail F, Hao YY, Yang JQ. G59S mutation in the GJB2 gene in a Chinese family with classic Vohwinkel syndrome. J Dermatol 2019; 46:154-157. [PMID: 30565282 DOI: 10.1111/1346-8138.14727] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 11/05/2018] [Indexed: 11/28/2022]
Abstract
Vohwinkel syndrome (VS) is a rare autosomal dominant condition, also known as mutilating palmoplantar keratoderma accompanied by sensorineural deafness. The LOR and GJB2 genes are reported to be responsible for VS. The GJB2 gene encodes connexin 26, a component of intercellular gap junctions expressed in various tissues. We report the case of a 31-year-old Chinese woman with classic VS characterized by sensorineural deafness and mutilating palmoplantar keratoderma. Further genetic studies demonstrated a nucleotide change (c.175G>A) in the GJB2 gene, leading to an amino acid alteration (G59S). This identical missense mutation (G59S) has also been reported in a patient with Bart-Pumphrey syndrome. Together with our findings and previous studies, we conclude that the identical mutation (G59S) in the GJB2 gene contributes to various manifestations.
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Affiliation(s)
- Ming-Xing Xie
- Department of Dermatology, Changxing Hospital, Huzhou, China
| | - Wei-Ping Yang
- Department of Stomatology, The First Affiliated Hospital of Huzhou University, Huzhou, China
| | - Hao-Jie Luo
- Department of Dermatology, The First Affiliated Hospital of Huzhou University, Huzhou, China
| | - Ferina Ismail
- Department of Dermatology, The Royal London Hospital, London, UK
| | - Yang-Yang Hao
- Department of Dermatology, The First Affiliated Hospital of Huzhou University, Huzhou, China
| | - Jian-Qiang Yang
- Department of Dermatology, The First Affiliated Hospital of Huzhou University, Huzhou, China
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17
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Youssefian L, Vahidnezhad H, Saeidian AH, Mahmoudi H, Karamzadeh R, Kariminejad A, Huang J, Li L, Jannace TF, Fortina P, Zeinali S, White TW, Uitto J. A novel autosomal recessive GJB2-associated disorder: Ichthyosis follicularis, bilateral severe sensorineural hearing loss, and punctate palmoplantar keratoderma. Hum Mutat 2018; 40:217-229. [PMID: 30431684 DOI: 10.1002/humu.23686] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 10/26/2018] [Accepted: 10/30/2018] [Indexed: 11/07/2022]
Abstract
Ichthyosis follicularis, a distinct cutaneous entity reported in combination with atrichia, and photophobia has been associated with mutations in MBTPS2. We sought the genetic cause of a novel syndrome of ichthyosis follicularis, bilateral severe sensorineural hearing loss and punctate palmoplantar keratoderma in two families. We performed whole exome sequencing on three patients from two families. The pathogenicity and consequences of mutations were studied in the Xenopus oocyte expression system and by molecular modeling analysis. Compound heterozygous mutations in the GJB2 gene were discovered: a pathogenic c.526A>G; p.Asn176Asp, and a common frameshift mutation, c.35delG; p.Gly12Valfs*2. The p.Asn176Asp missense mutation was demonstrated to significantly reduce the cell-cell gap junction channel activity and increase the nonjunctional hemichannel activity in the Xenopus oocyte expression system. Molecular modeling analyses of the mutant Cx26 protein revealed significant changes in the structural characteristics and electrostatic potential of the Cx26, either in hemichannel or gap junction conformation. Thus, association of a new syndrome of an autosomal recessive disorder of ichthyosis follicularis, bilateral severe sensorineural hearing loss and punctate palmoplantar keratoderma with mutations in GJB2, expands the phenotypic spectrum of the GJB2-associated disorders. The findings attest to the complexity of the clinical consequences of different mutations in GJB2.
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Affiliation(s)
- Leila Youssefian
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Genetics, Genomics and Cancer Biology PhD Program, Thomas Jefferson University, Philadelphia, PA, USA
| | - Hassan Vahidnezhad
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
- Biotechnology Research Center, Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran
| | - Amir Hossein Saeidian
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
- Genetics, Genomics and Cancer Biology PhD Program, Thomas Jefferson University, Philadelphia, PA, USA
| | - Hamidreza Mahmoudi
- Department of Dermatology, Razi Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Razieh Karamzadeh
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | | | - Jianhe Huang
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
| | - Leping Li
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Thomas F Jannace
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Paolo Fortina
- Department of Cancer Biology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
- Department of Molecular Medicine, Sapienza University, Rome, Italy
| | - Sirous Zeinali
- Biotechnology Research Center, Department of Molecular Medicine, Pasteur Institute of Iran, Tehran, Iran
| | - Thomas W White
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, USA
| | - Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
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18
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Guerra L, Castori M, Didona B, Castiglia D, Zambruno G. Hereditary palmoplantar keratodermas. Part II: syndromic palmoplantar keratodermas - Diagnostic algorithm and principles of therapy. J Eur Acad Dermatol Venereol 2018; 32:899-925. [DOI: 10.1111/jdv.14834] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 01/05/2018] [Indexed: 12/19/2022]
Affiliation(s)
- L. Guerra
- Laboratory of Molecular and Cell Biology; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - M. Castori
- Division of Medical Genetics; Casa Sollievo della Sofferenza-IRCCS; San Giovanni Rotondo Italy
| | - B. Didona
- Rare Skin Disease Center; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - D. Castiglia
- Laboratory of Molecular and Cell Biology; Istituto Dermopatico dell'Immacolata-IRCCS; Rome Italy
| | - G. Zambruno
- Genetic and Rare Diseases Research Area and Dermatology Unit; Bambino Gesù Children's Hospital-IRCCS; Rome Italy
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19
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Thiagarajan PS, Sinyuk M, Turaga SM, Mulkearns-Hubert EE, Hale JS, Rao V, Demelash A, Saygin C, China A, Alban TJ, Hitomi M, Torre-Healy LA, Alvarado AG, Jarrar A, Wiechert A, Adorno-Cruz V, Fox PL, Calhoun BC, Guan JL, Liu H, Reizes O, Lathia JD. Cx26 drives self-renewal in triple-negative breast cancer via interaction with NANOG and focal adhesion kinase. Nat Commun 2018; 9:578. [PMID: 29422613 PMCID: PMC5805730 DOI: 10.1038/s41467-018-02938-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 01/09/2018] [Indexed: 12/18/2022] Open
Abstract
Tumors adapt their phenotypes during growth and in response to therapies through dynamic changes in cellular processes. Connexin proteins enable such dynamic changes during development, and their dysregulation leads to disease states. The gap junction communication channels formed by connexins have been reported to exhibit tumor-suppressive functions, including in triple-negative breast cancer (TNBC). However, we find that connexin 26 (Cx26) is elevated in self-renewing cancer stem cells (CSCs) and is necessary and sufficient for their maintenance. Cx26 promotes CSC self-renewal by forming a signaling complex with the pluripotency transcription factor NANOG and focal adhesion kinase (FAK), resulting in NANOG stabilization and FAK activation. This FAK/NANOG-containing complex is not formed in mammary epithelial or luminal breast cancer cells. These findings challenge the paradigm that connexins are tumor suppressors in TNBC and reveal a unique function for Cx26 in regulating the core self-renewal signaling that controls CSC maintenance. Connexin proteins are usually considered as tumor suppressors. Here, the authors show that connexin 26 (Cx26) regulates the self-renewal of breast cancer stem cells via a ternary complex with FAK and NANOG.
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Affiliation(s)
- Praveena S Thiagarajan
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Maksim Sinyuk
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Soumya M Turaga
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Erin E Mulkearns-Hubert
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - James S Hale
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Vinay Rao
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Abeba Demelash
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Caner Saygin
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Arnab China
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Tyler J Alban
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Masahiro Hitomi
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Luke A Torre-Healy
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Alvaro G Alvarado
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Awad Jarrar
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Andrew Wiechert
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Valery Adorno-Cruz
- Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.,Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.,Departments of Pharmacology and Medicine, Northwestern University School of Medicine, Chicago, IL, 60611, USA
| | - Paul L Fox
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA.,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA
| | | | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Huiping Liu
- Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.,Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.,Departments of Pharmacology and Medicine, Northwestern University School of Medicine, Chicago, IL, 60611, USA
| | - Ofer Reizes
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA. .,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA. .,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.
| | - Justin D Lathia
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA. .,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA. .,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.
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20
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del Castillo FJ, del Castillo I. DFNB1 Non-syndromic Hearing Impairment: Diversity of Mutations and Associated Phenotypes. Front Mol Neurosci 2017; 10:428. [PMID: 29311818 PMCID: PMC5743749 DOI: 10.3389/fnmol.2017.00428] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 12/07/2017] [Indexed: 02/02/2023] Open
Abstract
The inner ear is a very complex sensory organ whose development and function depend on finely balanced interactions among diverse cell types. The many different kinds of inner ear supporting cells play the essential roles of providing physical and physiological support to sensory hair cells and of maintaining cochlear homeostasis. Appropriately enough, the gene most commonly mutated among subjects with hereditary hearing impairment (HI), GJB2, encodes the connexin-26 (Cx26) gap-junction channel protein that underlies both intercellular communication among supporting cells and homeostasis of the cochlear fluids, endolymph and perilymph. GJB2 lies at the DFNB1 locus on 13q12. The specific kind of HI associated with this locus is caused by recessively-inherited mutations that inactivate the two alleles of the GJB2 gene, either in homozygous or compound heterozygous states. We describe the many diverse classes of genetic alterations that result in DFNB1 HI, such as large deletions that either destroy the GJB2 gene or remove a regulatory element essential for GJB2 expression, point mutations that interfere with promoter function or splicing, and small insertions or deletions and nucleotide substitutions that target the GJB2 coding sequence. We focus on how these alterations disrupt GJB2 and Cx26 functions and on their different effects on cochlear development and physiology. We finally discuss the diversity of clinical features of DFNB1 HI as regards severity, age of onset, inner ear malformations and vestibular dysfunction, highlighting the areas where future research should be concentrated.
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Affiliation(s)
- Francisco J. del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
| | - Ignacio del Castillo
- Servicio de Genética, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Madrid, Spain
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21
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Leclère JC, Le Gac MS, Le Maréchal C, Ferec C, Marianowski R. GJB2 mutations: Genotypic and phenotypic correlation in a cohort of 690 hearing-impaired patients, toward a new mutation? Int J Pediatr Otorhinolaryngol 2017; 102:80-85. [PMID: 29106882 DOI: 10.1016/j.ijporl.2017.09.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 09/10/2017] [Accepted: 09/11/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To analyze the clinical features of hearing impairment and to search for correlations with the genotype in patients with GJB2 mutations. DESIGN Case series. SETTING Collaborative study in referral centers, institutional practice. PATIENTS A total of 690 hearing-impaired patients were genotypically and phenotypically described. The mutations of GJB2 and GJB6 were studied. Heterozygous patients were searched for another mutation by microsatellite approach. MAIN OUTCOME MEASURES Prevalence of GJB2 mutations, microsatellite approach, hearing-impairment. RESULTS In 498 patients (72,17% of the cohort), no mutation was found. Homozygotous patients were 59 (8,55%), with 51 for c.35delG, 6 for p.M34T and 2 for GJB6. Compound heterozygous were 64 (9,28%) with 56 c.35delG-others mutations. Genotypes with biallelic non sense mutations had a high risk of severe to profound hearing impairment. It was frequently milder in compound heterozygotes than in c.35delG homozygotes. Heterozygous patients were 69 (10%) with 21 c.35delG, 20 p.M34T and 28 others mutations. We selected patients with a complete historical medical file (clinical and audiometric data). Then, we performed a microsatellite approach (multiplex PCR of short DNA fragments) to localize a new pathologic allele. Seventeen heterozygous patients were studied. Six patients (35%) showed the same haplotype. They were compound heterozygous bearing a new pathologic allele. CONCLUSION Genotype may affect deafness severity, but environmental and other genetic factors may also modulate the severity and evolution of GJB2-GJB6 deafness. A new haplotype for GJB2 is described but the exact mutation remains unknown.
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Affiliation(s)
- Jean-Christophe Leclère
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France
| | - Marie-Suzanne Le Gac
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France
| | | | - Claude Ferec
- Genetic Department, University Hospital CHU Brest, France
| | - Rémi Marianowski
- Department of Otorhinolaryngology-Head and Neck Surgery, University Hospital CHU Brest, France.
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22
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Press E, Alaga KC, Barr K, Shao Q, Bosen F, Willecke K, Laird DW. Disease-linked connexin26 S17F promotes volar skin abnormalities and mild wound healing defects in mice. Cell Death Dis 2017; 8:e2845. [PMID: 28569788 PMCID: PMC5520893 DOI: 10.1038/cddis.2017.234] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/20/2017] [Accepted: 03/21/2017] [Indexed: 12/11/2022]
Abstract
Several mutant mice have been generated to model connexin (Cx)-linked skin diseases; however, the role of connexins in skin maintenance and during wound healing remains to be fully elucidated. Here we generated a novel, viable, and fertile mouse (Cx26CK14-S17F/+) with the keratitis-ichthyosis-deafness mutant (Cx26S17F) driven by the cytokeratin 14 promoter. This mutant mouse mirrors several Cx26-linked human skin pathologies suggesting that the etiology of Cx26-linked skin disease indeed stems from epidermal expression of the Cx26 mutant. Cx26CK14-S17F/+ foot pad epidermis formed severe palmoplantar keratoderma, which expressed elevated levels of Cx26 and filaggrin. Primary keratinocytes isolated from Cx26CK14-S17F/+ neonates exhibited reduced gap junctional intercellular communication and migration. Furthermore, Cx26CK14-S17F/+ mouse skin wound closure was normal but repaired epidermis appeared hyperplastic with elevated expression of cytokeratin 6. Taken together, we suggest that the Cx26S17F mutant disturbs keratinocyte differentiation and epidermal remodeling following wound closure. We further posit that Cx26 contributes to epidermal homeostasis by regulating keratinocyte differentiation, and that mice harboring a disease-linked Cx26 mutant display epidermal abnormalities yet retain most wound healing properties.
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Affiliation(s)
- Eric Press
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Katanya C Alaga
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Kevin Barr
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Qing Shao
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Felicitas Bosen
- LIMES (Life and Medical Sciences Institute), Molecular Genetics, University of Bonn, Bonn, Germany
| | - Klaus Willecke
- LIMES (Life and Medical Sciences Institute), Molecular Genetics, University of Bonn, Bonn, Germany
| | - Dale W Laird
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
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23
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Srinivas M, Verselis VK, White TW. Human diseases associated with connexin mutations. Biochim Biophys Acta Biomembr 2017; 1860:192-201. [PMID: 28457858 DOI: 10.1016/j.bbamem.2017.04.024] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 04/20/2017] [Accepted: 04/25/2017] [Indexed: 01/11/2023]
Abstract
Gap junctions and hemichannels comprised of connexins impact many cellular processes. Significant advances in our understanding of the functional role of these channels have been made by the identification of a host of genetic diseases caused by connexin mutations. Prominent features of connexin disorders are the inability of other connexins expressed in the same cell type to compensate for the mutated one, and the ability of connexin mutants to dominantly influence the activity of other wild-type connexins. Functional studies have begun to identify some of the underlying mechanisms whereby connexin channel mutation contributes to the disease state. Detailed mechanistic understanding of these functional differences will help to facilitate new pathophysiology driven therapies for the diverse array of connexin genetic disorders. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve.
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Affiliation(s)
- Miduturu Srinivas
- Department of Biological and Vision Sciences, SUNY College of Optometry, New York, NY 10036, USA
| | - Vytas K Verselis
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Thomas W White
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY 11794, USA.
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24
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Gruber R, Rogerson C, Windpassinger C, Banushi B, Straatman-Iwanowska A, Hanley J, Forneris F, Strohal R, Ulz P, Crumrine D, Menon GK, Blunder S, Schmuth M, Müller T, Smith H, Mills K, Kroisel P, Janecke AR, Gissen P. Autosomal Recessive Keratoderma-Ichthyosis-Deafness (ARKID) Syndrome Is Caused by VPS33B Mutations Affecting Rab Protein Interaction and Collagen Modification. J Invest Dermatol 2017; 137:845-854. [PMID: 28017832 PMCID: PMC5358661 DOI: 10.1016/j.jid.2016.12.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/30/2016] [Accepted: 12/02/2016] [Indexed: 12/21/2022]
Abstract
In this paper, we report three patients with severe palmoplantar keratoderma associated with ichthyosis and sensorineural deafness. Biallelic mutations were found in VPS33B, encoding VPS33B, a Sec1/Munc18 family protein that interacts with Rab11a and Rab25 proteins and is involved in trafficking of the collagen-modifying enzyme LH3. Two patients were homozygous for the missense variant p.Gly131Glu, whereas one patient was compound heterozygous for p.Gly131Glu and the splice site mutation c.240-1G>C, previously reported in patients with arthrogryposis renal dysfunction and cholestasis syndrome. We demonstrated the pathogenicity of variant p.Gly131Glu by assessing the interactions of the mutant VPS33B construct and its ability to traffic LH3. Compared with wild-type VPS33B, the p.Gly131Glu mutant VPS33B had reduced coimmunoprecipitation and colocalization with Rab11a and Rab25 and did not rescue LH3 trafficking. Confirming the cell-based experiments, we found deficient LH3-specific collagen lysine modifications in patients' urine and skin fibroblasts. Additionally, the epidermal ultrastructure of the p.Gly131Glu patients mirrored defects in tamoxifen-inducible VPS33B-deficient Vps33bfl/fl-ERT2 mice. Both patients and murine models revealed an impaired epidermal structure, ascribed to aberrant secretion of lamellar bodies, which are essential for epidermal barrier formation. Our results demonstrate that p.Gly131Glu mutant VPS33B causes an autosomal recessive keratoderma-ichthyosis-deafness syndrome.
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Key Words
- arc, arthrogryposis renal dysfunction and cholestasis
- arkid, autosomal recessive keratoderma-ichthyosis-deafness
- co-ip, co-immunoprecipitation
- corvet, core vacuole/endosome tethering
- hops, homotypic fusion and vacuole protein sorting
- lb, lamellar body
- mimcd3, murine inner medullary collecting duct 3
- ppk, palmoplantar keratoderma
- snp, single nucleotide polymorphism
- vws, vohwinkel syndrome
- wt, wild type
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Affiliation(s)
- Robert Gruber
- Department of Dermatology, Medical University of Innsbruck, Innsbruck, Austria; Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Clare Rogerson
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; Institute of Child Health, University College London, London, UK
| | | | - Blerida Banushi
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; Institute of Child Health, University College London, London, UK
| | - Anna Straatman-Iwanowska
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; Institute of Child Health, University College London, London, UK
| | - Joanna Hanley
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; Institute of Child Health, University College London, London, UK
| | - Federico Forneris
- The Armenise-Harvard Laboratory of Structural Biology, Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Robert Strohal
- Department of Dermatology, Academic Teaching Hospital Feldkirch, Feldkirch, Austria
| | - Peter Ulz
- Institute of Human Genetics, Medical University of Graz, Graz, Austria
| | - Debra Crumrine
- Department of Dermatology, Veterans Affairs Medical Center, University of California, San Francisco, California, USA
| | | | - Stefan Blunder
- Department of Dermatology, Medical University of Innsbruck, Innsbruck, Austria
| | - Matthias Schmuth
- Department of Dermatology, Medical University of Innsbruck, Innsbruck, Austria
| | - Thomas Müller
- Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria
| | - Holly Smith
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK
| | - Kevin Mills
- Institute of Child Health, University College London, London, UK
| | - Peter Kroisel
- Institute of Human Genetics, Medical University of Graz, Graz, Austria
| | - Andreas R Janecke
- Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria; Department of Pediatrics I, Medical University of Innsbruck, Innsbruck, Austria.
| | - Paul Gissen
- MRC Laboratory for Molecular Cell Biology, University College London, London, UK; Institute of Child Health, University College London, London, UK; Inherited Metabolic Diseases Unit, Great Ormond Street Hospital, London, UK.
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25
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Wang HH, Feng Y, Li HB, Wu H, Mei LY, Wang XW, Jiang L, He CF. Digenic mutations involving both the BSND and GJB2 genes detected in Bartter syndrome type IV. Int J Pediatr Otorhinolaryngol 2017; 92:17-20. [PMID: 28012523 DOI: 10.1016/j.ijporl.2016.10.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/23/2016] [Accepted: 10/24/2016] [Indexed: 11/30/2022]
Abstract
Bartter syndrome type IV, characterized by salt-losing nephropathies and sensorineural deafness, is caused by mutations of BSND or simultaneous mutations of both CLCNKA and CLCNKB. GJB2 is the primary causative gene for non-syndromic sensorineural deafness and associated with several syndromic sensorineural deafness. Owing to the rarity of Bartter syndrome, only a few mutations have been reported in the abovementioned causative genes. To investigate the underlying mutations in a Chinese patient with Bartter syndrome type IV, genetic analysis of BSND, CLCNKA, CLCNKB and GJB2 were performed by polymerase chain reaction and direct sequencing. Finally, double homozygous mutations c.22C > T (p.Arg8Trp) and c.127G > A (Val43Ile) were detected in exon 1 of BSND. Intriguingly, compound heterozygous mutations c.235delC (p.Leu79CysfsX3) and c.109G > A (p.Val37Ile) were also revealed in exon 2 of GJB2 in the same patient. No pathogenic mutations were found in CLCNKA and CLCNKB. Our results indicated that the homozygous mutation c.22C > T was the key genetic reason for the proband, and a digenic effect of BSND and GJB2 might contributed to sensorineural deafness. To our knowledge, it was the first report showing that the GJB2 gene mutations were detected in Bartter syndrome.
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Affiliation(s)
- Hong-Han Wang
- Department of Head and Neck Surgery, Hunan Cancer Hospital and the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, 410013, China
| | - Yong Feng
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China; State Key Laboratory of Medical Genetics, Changsha, 410078, Hunan, China; Province Key Laboratory of Otolaryngology Critical Diseases, Changsha, 410008, Hunan, China
| | - Hai-Bo Li
- Department of Ophtalmology, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Hong Wu
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Ling-Yun Mei
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Xing-Wei Wang
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Lu Jiang
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Chu-Feng He
- Department of Otolaryngology, Head & Neck Surgery, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China.
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26
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García IE, Prado P, Pupo A, Jara O, Rojas-Gómez D, Mujica P, Flores-Muñoz C, González-Casanova J, Soto-Riveros C, Pinto BI, Retamal MA, González C, Martínez AD. Connexinopathies: a structural and functional glimpse. BMC Cell Biol 2016; 17 Suppl 1:17. [PMID: 27228968 PMCID: PMC4896260 DOI: 10.1186/s12860-016-0092-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Mutations in human connexin (Cx) genes have been related to diseases, which we termed connexinopathies. Such hereditary disorders include nonsyndromic or syndromic deafness (Cx26, Cx30), Charcot Marie Tooth disease (Cx32), occulodentodigital dysplasia and cardiopathies (Cx43), and cataracts (Cx46, Cx50). Despite the clinical phenotypes of connexinopathies have been well documented, their pathogenic molecular determinants remain elusive. The purpose of this work is to identify common/uncommon patterns in channels function among Cx mutations linked to human diseases. To this end, we compiled and discussed the effect of mutations associated to Cx26, Cx32, Cx43, and Cx50 over gap junction channels and hemichannels, highlighting the function of the structural channel domains in which mutations are located and their possible role affecting oligomerization, gating and perm/selectivity processes.
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Affiliation(s)
- Isaac E García
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Pavel Prado
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Amaury Pupo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Oscar Jara
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Diana Rojas-Gómez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Paula Mujica
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carolina Flores-Muñoz
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Jorge González-Casanova
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Carolina Soto-Riveros
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Bernardo I Pinto
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Mauricio A Retamal
- Centro de Fisiología Celular e Integrativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Carlos González
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile.
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27
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Shuja Z, Li L, Gupta S, Meşe G, White TW. Connexin26 Mutations Causing Palmoplantar Keratoderma and Deafness Interact with Connexin43, Modifying Gap Junction and Hemichannel Properties. J Invest Dermatol 2016; 136:225-35. [PMID: 26763442 DOI: 10.1038/JID.2015.389] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 09/03/2015] [Accepted: 09/21/2015] [Indexed: 12/23/2022]
Abstract
Mutations in GJB2 (Cx26) cause either deafness, or deafness associated with skin diseases. That different disorders can be caused by distinct mutations within the same gene suggests that unique channel activities are influenced by each class of mutation. We have examined the functional characteristics of two human mutations, Cx26-H73R and Cx26-S183F, causing palmoplantar keratoderma (PPK) and deafness. Both failed to form gap junction channels or hemichannels when expressed alone. Co-expression of the mutants with wild-type Cx43 showed a trans-dominant inhibition of Cx43 gap junction channels, without reductions in Cx43 protein synthesis. In addition, the presence of mutant Cx26 shifted Cx43 channel gating and kinetics towards a more Cx26-like behavior. Co-immunoprecipitation showed Cx43 being pulled down more efficiently with mutant Cx26, than wild-type, confirming the enhanced formation of heteromeric connexons. Finally, the formation of heteromeric connexons resulted in significantly increased Cx43 hemichannel activity in the presence of Cx26 mutants. These findings suggest a common mechanism whereby Cx26 mutations causing PPK and deafness trans-dominantly influence multiple functions of wild-type Cx43. They also implicate a role for aberrant hemichannel activity in the pathogenesis of PPK, and further highlight an emerging role for Cx43 in genetic skin diseases.
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28
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Dalamón VK, Buonfiglio P, Larralde M, Craig P, Lotersztein V, Choate K, Pallares N, Diamante V, Elgoyhen AB. Connexin 26 (GJB2) mutation in an Argentinean patient with keratitis-ichthyosis-deafness (KID) syndrome: a case report. BMC Med Genet 2016; 17:37. [PMID: 27141831 PMCID: PMC4855445 DOI: 10.1186/s12881-016-0298-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 04/22/2016] [Indexed: 11/20/2022]
Abstract
Background Keratitis-Ichthyosis-Deafness (KID) syndrome is a rare condition characterized by pre-lingual sensorineural deafness with skin hyperkeratinization. The primary cause of the disease is a loss-of-function mutation in the GJB2 gene. Mutations in Argentinean patients have not been described. Case presentation We studied a 2 year-old boy with bilateral congenital sensorineural deafness with dry skin over the entire body, hypotrichosis of the scalp, thin and light-blond hair. Analysis of the GJB2 gene nucleotide sequence revealed the substitution of guanine-148 by adenine predicted to result in an Asp50Asn amino acid substitution. Conclusion This is the first KID report in a patient from Argentina. This de novo mutation proved to be the cause of keratitis-ichthyosis-deafness syndrome (KID-syndrome) in the patient, and has implications in medical genetic practice.
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Affiliation(s)
- Viviana Karina Dalamón
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor Torres"-(INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Vuelta de Obligado 2490. (1428) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina.
| | - Paula Buonfiglio
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor Torres"-(INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Vuelta de Obligado 2490. (1428) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Margarita Larralde
- Servicio de Dermatología Pediátrica, Hospital Ramos Mejía, Ciudad Autonoma de Buenos Aires, Argentina.,Departamento de Dermatología, Hospital Alemán, Ciudad Autonoma de Buenos Aires, Argentina
| | - Patricio Craig
- Departamento de Química Biológica e Instituto de Química y Fisicoquímica Biológicas, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autonoma de Buenos Aires, Argentina
| | - Vanesa Lotersztein
- Servicio de Genética, Hospital de Clínicas "José de San Martín", Ciudad Autonoma de Buenos Aires, Argentina
| | - Keith Choate
- Dermatology Yale University School of Medicine, New Haven, USA
| | - Norma Pallares
- Instituto Superior de Implantes Cocleares "Dr. Vicente Diamante", Ciudad Autonoma de Buenos Aires, Argentina
| | - Vicente Diamante
- Instituto Superior de Implantes Cocleares "Dr. Vicente Diamante", Ciudad Autonoma de Buenos Aires, Argentina
| | - Ana Belén Elgoyhen
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor Torres"-(INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Vuelta de Obligado 2490. (1428) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina.,Departamento de Farmacología, Facultad de Medicina, Universidad de Buenos Aires, Ciudad Autonoma de Buenos Aires, Argentina
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29
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Abstract
In this study, a Vohwinkel syndrome case is presented where in 5th digit constriction bands in the right hand were reconstructed using a distant abdominal skin flap. Vohwinkel syndrome, or keratoderma hereditarium mutilans, is a rare, autosomal dominant genetic skin condition that causes palmoplantar hyperkeratosis and constricts finger and/or toe bands. In a typical manifestation, the finger and toe constriction bands lead to progressive strangulation and autoamputation, which requires immediate clinical treatment. Topical keratolytics and systemic retinoids have been used to treat hyperkeratosis but without consistent results. Only 1 effective approach for autoamputation has been accepted, reconstructive surgery.Applying a distant abdominal skin flap produced satisfying postoperative effects at the 18-month follow-up.
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Affiliation(s)
- Mingzi Zhang
- From the Department of Plastic Surgery, Peking Union Medical College Hospital, Beijing (MZ, KS, YW); Department of Neurosurgery, Qingdao Huangdao District Hospital of Traditional Chinese Medicine, Qingdao, Shandong (ND); and Department of Dermatology, Peking Union Medical College Hospital, Beijing, China (CS)
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30
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Lilly E, Sellitto C, Milstone LM, White TW. Connexin channels in congenital skin disorders. Semin Cell Dev Biol 2016; 50:4-12. [PMID: 26775130 DOI: 10.1016/j.semcdb.2015.11.018] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 11/23/2015] [Indexed: 11/22/2022]
Abstract
Gap junctions and hemichannels comprised of connexins influence epidermal proliferation and differentiation. Significant advances in our understanding of the functional role of connexins in the skin have been made by studying the diseases caused by connexin mutations. Eleven clinically defined cutaneous disorders with an overlapping spectrum of phenotypes are caused by mutations in five different connexin genes, highlighting that disease presentation must be deciphered with an understanding of how connexin functions are affected. Increasing evidence suggests that the skin diseases produced by connexin mutations result from dominant gains of function. In palmoplantar keratoderma with deafness, the connexin 26 mutations transdominantly alter the function of wild-type connexin 43 and create leaky heteromeric hemichannels. In keratitis-ichthyosis-deafness syndrome, different connexin 26 mutations can either form dominant hemichannels with altered calcium regulation or increased calcium permeability, leading to clinical subtypes of this syndrome. It is only with detailed understanding of these subtle functional differences that we can hope to create successful pathophysiology driven therapies for the connexin skin disorders.
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31
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Pandey N, Xavier DF, Chatterjee A, Mani RS, Hiremagalore R, Tharakan A, Rajashekhar B, Anand A. Functional Analysis of a Novel Connexin30 Mutation in a Large Family with Hearing Loss, Pesplanus, Ichthyosis, Cutaneous Nodules, and Keratoderma. Ann Hum Genet 2015; 80:11-9. [PMID: 26620415 DOI: 10.1111/ahg.12141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 09/11/2015] [Indexed: 11/28/2022]
Abstract
Mutations in the gap-junction gene Cx30 (Connexin30, GJB6) are a known cause of hearing loss. Here, we report our findings on a large multigeneration family in which severe to profound sensorineural hearing impairment is associated with a variety of skin-related anomalies. Genome-wide analysis of the family showed that the locus maps to chromosome region 13ptel-q12.1 and that a novel mutation, p.N54K, in Cx30, cosegregates with the phenotype. Unlike wild-type Cx30, p.N54K Cx30 is predominantly localized in the cytoplasm and does not permit transfer of neurobiotin, suggesting improper cellular localization and abolishment of gap-junction activity.
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Affiliation(s)
- Nishtha Pandey
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India.,Centre for Human Genetics, Bangalore, India
| | - Dennis F Xavier
- Department of Speech and Hearing, School of Allied Health Sciences, Manipal University, Manipal, India
| | - Arunima Chatterjee
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Ram-Shankar Mani
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | | | - Ajith Tharakan
- Department of Dermatology, Sree Narayana Institute of Medical Sciences, Cochin, India
| | - B Rajashekhar
- Department of Speech and Hearing, School of Allied Health Sciences, Manipal University, Manipal, India
| | - Anuranjan Anand
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
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32
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Yao F, Yue M, Zhang C, Zuo X, Zheng X, Zhang A, Wang Z, Liu S, Li H, Meng L, Zeng M, Fan X, Sun L, Zhang X. A genetic coding variant rs72474224 in GJB2 is associated with clinical features of psoriasis vulgaris in a Chinese Han population. ACTA ACUST UNITED AC 2015; 86:134-8. [PMID: 26104599 DOI: 10.1111/tan.12595] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 04/22/2015] [Accepted: 05/22/2015] [Indexed: 12/19/2022]
Abstract
Our recent targeted sequencing study identified a missense single-nucleotide polymorphism rs72474224 (c.324C>T) in GJB2. To investigate the correlation between rs72474224 (c.324C>T) and subphenotypes of psoriasis, genotype data for rs72474224 (c.324C>T, p.Val37Ile) was analyzed in 9946 cases and 9906 controls. The additive model provided the best fit for rs72474224 (P = 7.34 × 10(-9)). The genotypic and allelic frequency distributions were associated with plaque psoriasis in case-only (Pgenotype = 2.67 × 10(-3), Pallele = 6.22 × 10(-4)) and subphenotype-control (Pgenotype = 1.58 × 10(-11), Pallele = 8.16 × 10(-12)) analyses. No other significant difference was found in case-only analyses. Rs72474224 in GJB2 is preferentially associated with plaque psoriasis in Chinese population and might contribute to the complexity of psoriasis clinical features.
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Affiliation(s)
- F Yao
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Department of Dermatology at Anqing Hospital, Anhui Medical University, Hefei, China
| | - M Yue
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - C Zhang
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - X Zuo
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - X Zheng
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - A Zhang
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - Z Wang
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - S Liu
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - H Li
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - L Meng
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - M Zeng
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - X Fan
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - L Sun
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
| | - X Zhang
- Institute of Dermatology and Department of Dermatology, Anhui Medical University, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China
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Martin PE, van Steensel M. Connexins and skin disease: insights into the role of beta connexins in skin homeostasis. Cell Tissue Res 2015; 360:645-58. [PMID: 25616557 DOI: 10.1007/s00441-014-2094-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 12/08/2014] [Indexed: 12/20/2022]
Abstract
Cell-to-cell communication triggered by connexin channels plays a central role in maintaining epidermal homeostasis. Here, we discuss the role of the beta connexin subgroup, where site-specific mutations in at least 4 of these proteins lead to distinctive non-inflammatory and inflammatory hyperproliferative epidermal disorders. Recent advances in the molecular pathways evoked and correlation with clinical outcome are discussed. The latest data provide increasing evidence that connexins in the epidermis are sensors to environmental stress and that targeting aberrant hemichannel activity holds significant therapeutic potential for inflammatory skin disorders.
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Lagou M, Papoulidis I, Orru S, Papadopoulos V, Daskalakis G, Kontodiou M, Anastasakis E, Petersen MB, Kitsos G, Thomaidis L, Manolakos E. A de novo 2.9 Mb interstitial deletion at 13q12.11 in a child with developmental delay accompanied by mild dysmorphic characteristics. Mol Cytogenet 2014; 7:92. [PMID: 25506395 PMCID: PMC4265435 DOI: 10.1186/s13039-014-0092-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 11/23/2014] [Indexed: 11/24/2022] Open
Abstract
Background Proximal deletions in the 13q12.11 region are very rare. Much larger deletions including this region have been described and are associated with complex phenotypes of mental retardation, developmental delay and various others anomalies. Results We report on a 3-year-old girl with a rare 2.9 Mb interstitial deletion at 13q12.11 due to a de novo unbalanced t(13;14) translocation. She had mild mental retardation and relatively mild dysmorphic features such as microcephaly, flat nasal bridge, moderate micrognathia and clinodactyly of 5th finger. Molecular karyotyping revealed a deletion on the long arm of chromosome 13 as involving sub-bands 13q12.11, a deletion of about 2.9 Mb. Discussion The clinical application of array-CGH has made it possible to detect submicroscopical genomic rearrangements that are associated with varying phenotypes.The description of more patients with deletions of the 13q12.11 region will allow a more precise genotype-phenotype correlation.
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Affiliation(s)
| | - Ioannis Papoulidis
- Eurogenetica S.A., Laboratory of Genetics, Michalakopoulou 125& Vervainon 14, 11527 Athens, Thessaloniki Greece
| | - Sandro Orru
- Department of Medical Genetics, University of Cagliari, Binaghi Hospital, Cagliari, Italy
| | | | - George Daskalakis
- 1st Department of Obstetrics & Gynecology, University of Athens, Athens, Greece
| | - Maria Kontodiou
- Eurogenetica S.A., Laboratory of Genetics, Michalakopoulou 125& Vervainon 14, 11527 Athens, Thessaloniki Greece
| | | | - Michael B Petersen
- Department of Clinical Medicine, The Faculty of Medicine, Aalborg University Hospital, Aalborg, Denmark
| | - George Kitsos
- Department of Ophthalmology, University of Ioannina, Ioannina, Greece
| | - Loretta Thomaidis
- Developmental Assessment Unit, 2nd Department of Pediatrics, P. & A. Kyriakou Children's Hospital, National and Kapodistrian University of Athens, School of Medicine, Athens, Greece
| | - Emmanouil Manolakos
- Eurogenetica S.A., Laboratory of Genetics, Michalakopoulou 125& Vervainon 14, 11527 Athens, Thessaloniki Greece ; Department of Medical Genetics, University of Cagliari, Binaghi Hospital, Cagliari, Italy
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Abstract
Normal development, function and repair of the sensory epithelia in the inner ear are all dependent on gap junctional intercellular communication. Mutations in the connexin genes GJB2 and GJB6 (encoding CX26 and CX30) result in syndromic and non-syndromic deafness via various mechanisms. Clinical vestibular defects, however, are harder to connect with connexin dysfunction. Cx26 and Cx30 proteins are widely expressed in the epithelial and connective tissues of the cochlea, where they may form homomeric or heteromeric gap junction channels in a cell-specific and spatiotemporally complex fashion. Despite the study of mutant channels and animal models for both recessive and dominant autosomal deafness, it is still unclear why gap junctions are essential for auditory function, and why Cx26 and Cx30 do not compensate for each other in vivo. Cx26 appears to be essential for normal development of the auditory sensory epithelium, but may be dispensable during normal hearing. Cx30 appears to be essential for normal repair following sensory cell loss. The specific modes of intercellular signalling mediated by inner ear gap junction channels remain undetermined, but they are hypothesised to play essential roles in the maintenance of ionic and metabolic homeostasis in the inner ear. Recent studies have highlighted involvement of gap junctions in the transfer of essential second messengers between the non-sensory cells, and have proposed roles for hemichannels in normal hearing. Here, we summarise the current knowledge about the molecular and functional properties of inner ear gap junctions, and about tissue pathologies associated with connexin mutations.
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Affiliation(s)
- Daniel J Jagger
- UCL Ear Institute, University College London, 332 Gray's Inn Road, London, WC1X 8EE, UK,
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Xiao D, Chen S, Shao Q, Chen J, Bijian K, Laird DW, Alaoui-Jamali MA. Dynamin 2 interacts with connexin 26 to regulate its degradation and function in gap junction formation. Int J Biochem Cell Biol 2014; 55:288-97. [DOI: 10.1016/j.biocel.2014.09.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 09/09/2014] [Accepted: 09/19/2014] [Indexed: 11/16/2022]
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Wang H, Cao X, Lin Z, Lee M, Jia X, Ren Y, Dai L, Guan L, Zhang J, Lin X, Zhang J, Chen Q, Feng C, Zhou EY, Yin J, Xu G, Yang Y. Exome sequencing reveals mutation in GJA1 as a cause of keratoderma-hypotrichosis-leukonychia totalis syndrome. Hum Mol Genet 2014; 24:243-50. [DOI: 10.1093/hmg/ddu442] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Rorke EA, Adhikary G, Young CA, Roop DR, Eckert RL. Suppressing AP1 factor signaling in the suprabasal epidermis produces a keratoderma phenotype. J Invest Dermatol 2014; 135:170-180. [PMID: 25050598 DOI: 10.1038/jid.2014.310] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Revised: 03/21/2014] [Accepted: 04/10/2014] [Indexed: 11/09/2022]
Abstract
Keratodermas comprise a heterogeneous group of highly debilitating and painful disorders characterized by thickening of the skin with marked hyperkeratosis. Some of these diseases are caused by genetic mutation, whereas other forms are acquired in response to environmental factors. Our understanding of signaling changes that underlie these diseases is limited. In the present study, we describe a keratoderma phenotype in mice in response to suprabasal epidermis-specific inhibition of activator protein 1 transcription factor signaling. These mice develop a severe phenotype characterized by hyperplasia, hyperkeratosis, parakeratosis, and impaired epidermal barrier function. The skin is scaled, constricting bands encircle the tail and digits, the footpads are thickened and scaled, and loricrin staining is markedly reduced in the cornified layers and increased in the nucleus. Features of this phenotype, including nuclear loricrin localization and pseudoainhum (autoamputation), are characteristic of the Vohwinkel syndrome. We confirm that the phenotype develops in a loricrin-null genetic background, indicating that suppressed suprabasal AP1 factor function is sufficient to drive this disease. We also show that the phenotype regresses when suprabasal AP1 factor signaling is restored. Our findings suggest that suppression of AP1 factor signaling in the suprabasal epidermis is a key event in the pathogenesis of keratoderma.
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Affiliation(s)
- Ellen A Rorke
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gautam Adhikary
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Christina A Young
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dennis R Roop
- Department of Dermatology and Charles C. Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Richard L Eckert
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland, USA; Department of Dermatology, University of Maryland School of Medicine, Baltimore, Maryland, USA; Department of Obstetrics and Gynecology and Reproductive Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA.
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Pang X, Chai Y, Sun L, Chen D, Chen Y, Zhang Z, Wu H, Yang T. Characterization of spectrum, de novo rate and genotype-phenotype correlation of dominant GJB2 mutations in Chinese hans. PLoS One 2014; 9:e100483. [PMID: 24945352 PMCID: PMC4063943 DOI: 10.1371/journal.pone.0100483] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Accepted: 05/23/2014] [Indexed: 11/18/2022] Open
Abstract
Dominant mutations in GJB2 may lead to various degrees of sensorineural hearing impairment and/or hyperproliferative epidermal disorders. So far studies of dominant GJB2 mutations were mostly limited to case reports of individual patients and families. In this study, we identified 7 families, 11 subjects with dominant GJB2 mutations by sequencing of GJB2 in 2168 Chinese Han probands with sensorineural hearing impairment and characterized the associated spectrum, de novo rate and genotype-phenotype correlation. We identified p.R75Q, p.R75W and p.R184Q as the most frequent dominant GJB2 mutations among Chinese Hans, which had a very high de novo rate (71% of probands). A majority (10/11) of subjects carrying dominant GJB2 mutations exhibited palmoplantar keratoderma in addition to hearing impairment. In two families segregated with additional c.235delC or p.V37I mutations of GJB2, family members with the compound heterozygous mutations exhibited more severe phenotype than those with single dominant GJB2 mutation. Our study suggested that the high de novo mutation rate gives rise to a significant portion of dominant GJB2 mutations. The severity of the hearing and epidermal phenotypes associated with dominant GJB2 mutations may be modified by additional recessive mutations of GJB2.
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Affiliation(s)
- Xiuhong Pang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Yongchuan Chai
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Lianhua Sun
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Dongye Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Ying Chen
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Zhihua Zhang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Hao Wu
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
| | - Tao Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Ear Institute, Shanghai Jiaotong University, Shanghai, China
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Pavone P, Briuglia S, Falsaperla R, Warm A, Pavone V, Bernardini L, Novelli A, Praticò AD, Salpietro V, Ruggieri M. Wide spectrum of congenital anomalies including choanal atresia, malformed extremities, and brain and spinal malformations in a girl with a de novo 5.6-Mb deletion of 13q12.11-13q12.13. Am J Med Genet A 2014; 164A:1734-43. [PMID: 24807585 DOI: 10.1002/ajmg.a.36391] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 11/07/2013] [Indexed: 01/31/2023]
Abstract
A 2 ½-year-old girl with multiple congenital anomalies and a de novo 5.6-Mb deletion on chromosome 13q12.11-13q12.13 is reported. She showed choanal atresia, scalp aplasia cutis, mild dysmorphic features, severe malformation of the hands and feet, Sylvian aqueductal stenosis, hydrocephalus, small cerebellum with pointed cerebellar tonsils, cervical, lumbar and sacral clefting, single central incisor and mild developmental delay. The girl's anomalies were compared with: (A) one boy reported by each of Der Kaloustian et al. [2011] and Tanteles et al. [2011] with similar, albeit smaller, 2.1 to 2.9 Mb deletions in which the abnormalities consisted of mild facial dysmorphism, mild malformations of the fingers and/or toes, and developmental delay; (B) one girl reported by Friedman et al. [2006] with similar, albeit larger, 5.7 Mb deletion with mild developmental delay and haematological abnormalities; (C) one girl reported by Slee et al. [1991] with a deletion of band q12.2 in chromosome 13, who had Moebius syndrome with facial dysmorphism, high arched palate, micrognathia, and small tongue with no abnormalities of the extremities; and (D) seven additional individuals recorded in the DECIPHER 6.0 database who all had dysmorphic features and developmental delay plus a spectrum of clinical manifestations including deafness, ataxia/oculomotor apraxia, spasticity, small testes, and mild fingers' anomalies. The deleted region hereby reported encompassed 34 known genes, including GJA3, GJB2, and GJB6, which are responsible for autosomal recessive deafness, FGF9, which plays crucial roles in embryonic neurological development, and ATP8A2, which causes a cerebellar ataxia and disequilibrium syndrome.
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Affiliation(s)
- Piero Pavone
- Unit of Pediatrics and Pediatric Emergency, University Hospital "Policlinico-Vittorio Emanuele", Catania, Italy
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Martin PE, Easton JA, Hodgins MB, Wright CS. Connexins: sensors of epidermal integrity that are therapeutic targets. FEBS Lett 2014; 588:1304-14. [PMID: 24607543 DOI: 10.1016/j.febslet.2014.02.048] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 02/25/2014] [Accepted: 02/25/2014] [Indexed: 12/25/2022]
Abstract
Gap junction proteins (connexins) are differentially expressed throughout the multiple layers of the epidermis. A variety of skin conditions arise with aberrant connexin expression or function and suggest that maintaining the epidermal gap junction network has many important roles in preserving epidermal integrity and homeostasis. Mutations in a number of connexins lead to epidermal dysplasias giving rise to a range of dermatological disorders of differing severity. 'Gain of function' mutations reveal connexin-mediated roles in calcium signalling within the epidermis. Connexins are involved in epidermal innate immunity, inflammation control and in wound repair. The therapeutic potential of targeting connexins to improve wound healing responses is now clear. This review discusses the role of connexins in epidermal integrity, and examines the emerging evidence that connexins act as epidermal sensors to a variety of mechanical, temperature, pathogen-induced and chemical stimuli. Connexins thus act as an integral component of the skin's protective barrier.
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Affiliation(s)
- Patricia E Martin
- Department of Life Sciences and Institute for Applied Health Research, Glasgow Caledonian University, Glasgow G4 0BA, UK.
| | - Jennifer A Easton
- Department of Life Sciences and Institute for Applied Health Research, Glasgow Caledonian University, Glasgow G4 0BA, UK; Department of Dermatology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Malcolm B Hodgins
- Department of Life Sciences and Institute for Applied Health Research, Glasgow Caledonian University, Glasgow G4 0BA, UK
| | - Catherine S Wright
- Department of Life Sciences and Institute for Applied Health Research, Glasgow Caledonian University, Glasgow G4 0BA, UK
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Wikramanayake TC, Stojadinovic O, Tomic-Canic M. Epidermal Differentiation in Barrier Maintenance and Wound Healing. Adv Wound Care (New Rochelle) 2014; 3:272-280. [PMID: 24669361 DOI: 10.1089/wound.2013.0503] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Accepted: 11/06/2013] [Indexed: 12/20/2022] Open
Abstract
Significance: The epidermal barrier prevents water loss and serves as the body's first line of defense against toxins, chemicals, and infectious microbes. Disruption of the barrier, either through congenital disorders of barrier formation or through wounds, puts the individual at risk for dehydration, hypersensitivity, infection, and prolonged inflammation. Epidermal barrier disorders affect millions of patients in the United States, causing loss of productivity and diminished quality of life for patients and their families, and represent a burden to the health-care system and society. Recent Advances: The genetic basis of many congenital barrier disorders has been identified in recent years, and great advances have been made in the molecular mechanisms of the formation and homeostasis of epidermal barrier, as well as acute and chronic wound healing. Progress in stem cell (SC) biology, particularly in induced pluripotent stem cells (iPSCs) and allogeneic mesenchymal stem cells (MSCs), has opened new doors for cell-based therapy of chronic wounds. Critical Issues: Understanding of the molecular mechanisms of barrier homeostasis in health and disease, as well as contributions of iPSCs and allogeneic MSCs to wound healing, will lead to the identification of novel targets for developing therapeutics for congenital barrier and wound healing disorders. Future Directions: Future studies should focus on better understanding of molecular mechanisms leading to disrupted homeostasis of epidermal barrier to identify potential therapeutic targets to combat its associated diseases.
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Affiliation(s)
- Tongyu Cao Wikramanayake
- Wound Healing and Regenerative Medicine Research Program, Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida
- Molecular Cell and Developmental Biology Program, University of Miami Miller School of Medicine, Miami, Florida
| | - Olivera Stojadinovic
- Wound Healing and Regenerative Medicine Research Program, Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida
| | - Marjana Tomic-Canic
- Wound Healing and Regenerative Medicine Research Program, Department of Dermatology and Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida
- Cellular and Molecular Pharmacology Graduate Program in Biomedical Sciences; University of Miami Miller School of Medicine, Miami, Florida
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Adeyo O, Allan BB, Barnes RH 2nd, Goulbourne CN, Tatar A, Tu Y, Young LC, Weinstein MM, Tontonoz P, Fong LG, Beigneux AP, Young SG. Palmoplantar keratoderma along with neuromuscular and metabolic phenotypes in Slurp1-deficient mice. J Invest Dermatol 2014; 134:1589-98. [PMID: 24499735 DOI: 10.1038/jid.2014.19] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 12/03/2013] [Accepted: 12/07/2013] [Indexed: 01/11/2023]
Abstract
Mutations in SLURP1 cause mal de Meleda, a rare palmoplantar keratoderma (PPK). SLURP1 is a secreted protein that is expressed highly in keratinocytes but has also been identified elsewhere (e.g., spinal cord neurons). Here, we examined Slurp1-deficient mice (Slurp1−/−) created by replacing exon 2 with β-gal and neo cassettes. Slurp1−/− mice developed severe PPK characterized by increased keratinocyte proliferation, an accumulation of lipid droplets in the stratum corneum, and a water barrier defect. In addition, Slurp1−/− mice exhibited reduced adiposity, protection from obesity on a high-fat diet, low plasma lipid levels, and a neuromuscular abnormality (hind limb clasping). Initially, it was unclear whether the metabolic and neuromuscular phenotypes were due to Slurp1 deficiency because we found that the targeted Slurp1 mutation reduced the expression of several neighboring genes (e.g., Slurp2, Lypd2). We therefore created a new line of knockout mice (Slurp1X−/− mice) with a simple nonsense mutation in exon 2. The Slurp1X mutation did not reduce the expression of adjacent genes, but Slurp1X−/− mice exhibited all of the phenotypes observed in the original line of knockout mice. Thus, Slurp1 deficiency in mice elicits metabolic and neuromuscular abnormalities in addition to PPK.
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de Zwart-Storm EA, Martin PE, van Steensel MAM. Gap junction diseases of the skin: novel insights from new mutations. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/edm.09.47] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Abstract
Hearing loss has a genetic etiology in the majority of cases and is very common. The universal newborn hearing screening program, together with remarkable recent progress in the characterization of genes associated with the function of hearing, have resulted in increased demand and exciting possibilities of detecting the molecular basis of hereditary hearing loss through DNA testing. Future molecular diagnostic assays are expected to offer a greater variety of gene-specific tests, as well as combined mutation panels, which will aid in the management of the impressive genetic heterogeneity observed in hereditary hearing loss, especially in individuals with nonsyndromic forms. This review addresses the genetics of hearing loss, discusses the most commonly offered genetic assays for nonsyndromic hearing loss, with advantages and limitations, proposes a practical testing algorithm, and highlights current developments.
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Affiliation(s)
- Iris Schrijver
- Stanford University School of Medicine, Department of Pathology & Pediatrics, L235, 300 Pasteur Drive, Stanford, CA 94305, USA.
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46
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Abstract
In the present review, we provide an overview of connexin expression during skin development and remodeling in wound healing, and reflect on how loss- or gain-of-function connexin mutations may change cellular phenotypes and lead to diseases of the skin. We also consider the therapeutic value of targeting connexins in wound healing.
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Affiliation(s)
- Jared M Churko
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada
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47
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Kubo A, Shiohama A, Sasaki T, Nakabayashi K, Kawasaki H, Atsugi T, Sato S, Shimizu A, Mikami S, Tanizaki H, Uchiyama M, Maeda T, Ito T, Sakabe JI, Heike T, Okuyama T, Kosaki R, Kosaki K, Kudoh J, Hata K, Umezawa A, Tokura Y, Ishiko A, Niizeki H, Kabashima K, Mitsuhashi Y, Amagai M. Mutations in SERPINB7, encoding a member of the serine protease inhibitor superfamily, cause Nagashima-type palmoplantar keratosis. Am J Hum Genet 2013; 93:945-56. [PMID: 24207119 DOI: 10.1016/j.ajhg.2013.09.015] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 09/19/2013] [Accepted: 09/25/2013] [Indexed: 10/26/2022] Open
Abstract
"Nagashima-type" palmoplantar keratosis (NPPK) is an autosomal recessive nonsyndromic diffuse palmoplantar keratosis characterized by well-demarcated diffuse hyperkeratosis with redness, expanding on to the dorsal surfaces of the palms and feet and the Achilles tendon area. Hyperkeratosis in NPPK is mild and nonprogressive, differentiating NPPK clinically from Mal de Meleda. We performed whole-exome and/or Sanger sequencing analyses of 13 unrelated NPPK individuals and identified biallelic putative loss-of-function mutations in SERPINB7, which encodes a cytoplasmic member of the serine protease inhibitor superfamily. We identified a major causative mutation of c.796C>T (p.Arg266(∗)) as a founder mutation in Japanese and Chinese populations. SERPINB7 was specifically present in the cytoplasm of the stratum granulosum and the stratum corneum (SC) of the epidermis. All of the identified mutants are predicted to cause premature termination upstream of the reactive site, which inhibits the proteases, suggesting a complete loss of the protease inhibitory activity of SERPINB7 in NPPK skin. On exposure of NPPK lesional skin to water, we observed a whitish spongy change in the SC, suggesting enhanced water permeation into the SC due to overactivation of proteases and a resultant loss of integrity of the SC structure. These findings provide an important framework for developing pathogenesis-based therapies for NPPK.
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Volo T, Sathiyaseelan T, Astolfi L, Guaran V, Trevisi P, Emanuelli E, Martini A. Hair phenotype in non-syndromic deafness. Int J Pediatr Otorhinolaryngol 2013; 77:1280-5. [PMID: 23751281 DOI: 10.1016/j.ijporl.2013.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 10/26/2022]
Abstract
The GJB2 gene is located on chromosome 13q12 and it encodes the connexin 26, a transmembrane protein involved in cell-cell attachment of almost all tissues. GJB2 mutations cause autosomal recessive (DFNB1) and sometimes dominant (DFNA3) non-syndromic sensorineural hearing loss. Moreover, it has been demonstrated that connexins are involved in regulation of growth and differentiation of epidermal tissues. Hence, mutations in GJB2 gene, which is responsible for non-syndromic deafness, may be associated with an abnormal skin and hair phenotype. We analyzed hair samples from 96 subjects: a study group of 42 patients with hearing impairments of genetic origin (38 with a non-syndromic form, 4 with a syndromic form), and a control group including 54 people, i.e. 43 patients with other, non-genetic hearing impairments and 11 healthy volunteers aged up to 10 years old. The surface structure of 49 hair samples was normal, whereas in 45 cases it was altered, with a damaged appearance. Two hair samples were considered unclassifiable: one from the patient heterozygotic for the pendrin mutation (Fig. 2C), the other from a patient from Ghana with a R134W mutation (Fig. 2D). Among the 43 altered hair samples, 31 belonged to patients with connexin mutations and the other 12 came from patients without connexin mutations.
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Affiliation(s)
- T Volo
- Otolaryngology and Otosurgery Unit, University Hospital of Padova, Italy.
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Williams P, Memon A, Sinha T, Fryer A. Connecting with connexins. Australas J Dermatol 2013; 54:287-9. [PMID: 23808595 DOI: 10.1111/ajd.12070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 02/03/2013] [Indexed: 11/28/2022]
Abstract
We describe a case of an 18-year-old woman with congenital sensorineural deafness who presented to the dermatology clinic with asymptomatic thickening of the skin over the palmar aspect of her hands and feet. An examination revealed palmoplantar keratoderma of the palms and soles of the feet with no pseudoainhum. Her father wore a hearing aid and his deafness had been thought to be acquired. Mutation analysis of the connexin 26 gene revealed that she carried a paternally inherited mutation, p.Asp46Glu and a maternally inherited M34T variant. The p.Asp46Glu mutation has been described in a family exhibiting non-syndromic autosomal dominant deafness. Although the M34T variant has been described as a non-pathogenic variant or with a very mild phenotype only, its combination with the p.Asp46Glu mutation may account for her mild cutaneous phenotype with later clinical presentation.
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Affiliation(s)
- Penelope Williams
- Department of Dermatology, Royal Liverpool and Broadgreen Hospital NHS Trust, Southport, UK
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Affiliation(s)
| | - Jordan Fabrikant
- Texas Division; Department of Dermatology; Larkin Community Hospital; Miami FL USA
| | - Angie Koriakos
- Department of Dermatology; University of North Texas Health Science Center/Texas College of Osteopathic Medicine; Houston TX USA
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