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Yasarbas SS, Inal E, Yildirim MA, Dubrac S, Lamartine J, Mese G. Connexins in epidermal health and diseases: insights into their mutations, implications, and therapeutic solutions. Front Physiol 2024; 15:1346971. [PMID: 38827992 PMCID: PMC11140265 DOI: 10.3389/fphys.2024.1346971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 04/15/2024] [Indexed: 06/05/2024] Open
Abstract
The epidermis, the outermost layer of the skin, serves as a protective barrier against external factors. Epidermal differentiation, a tightly regulated process essential for epidermal homeostasis, epidermal barrier formation and skin integrity maintenance, is orchestrated by several players, including signaling molecules, calcium gradient and junctional complexes such as gap junctions (GJs). GJ proteins, known as connexins facilitate cell-to-cell communication between adjacent keratinocytes. Connexins can function as either hemichannels or GJs, depending on their interaction with other connexons from neighboring keratinocytes. These channels enable the transport of metabolites, cAMP, microRNAs, and ions, including Ca2+, across cell membranes. At least ten distinct connexins are expressed within the epidermis and mutations in at least five of them has been linked to various skin disorders. Connexin mutations may cause aberrant channel activity by altering their synthesis, their gating properties, their intracellular trafficking, and the assembly of hemichannels and GJ channels. In addition to mutations, connexin expression is dysregulated in other skin conditions including psoriasis, chronic wound and skin cancers, indicating the crucial role of connexins in skin homeostasis. Current treatment options for conditions with mutant or altered connexins are limited and primarily focus on symptom management. Several therapeutics, including non-peptide chemicals, antibodies, mimetic peptides and allele-specific small interfering RNAs are promising in treating connexin-related skin disorders. Since connexins play crucial roles in maintaining epidermal homeostasis as shown with linkage to a range of skin disorders and cancer, further investigations are warranted to decipher the molecular and cellular alterations within cells due to mutations or altered expression, leading to abnormal proliferation and differentiation. This would also help characterize the roles of each isoform in skin homeostasis, in addition to the development of innovative therapeutic interventions. This review highlights the critical functions of connexins in the epidermis and the association between connexins and skin disorders, and discusses potential therapeutic options.
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Affiliation(s)
- S. Suheda Yasarbas
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - Ece Inal
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - M. Azra Yildirim
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
| | - Sandrine Dubrac
- Department of Dermatology, Venereology and Allergology, Medical University of Innsbruck, Innsbruck, Austria
| | - Jérôme Lamartine
- Skin Functional Integrity Group, Laboratory for Tissue Biology and Therapeutics Engineering (LBTI) CNRS UMR5305, University of Lyon, Lyon, France
| | - Gulistan Mese
- Izmir Institute of Technology, Faculty of Science, Department of Molecular Biology and Genetics, Izmir, Turkiye
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Muramatsu J, Arihara Y, Yoshida M, Kubo T, Nakamura H, Ishikawa K, Fujita H, Sugita S, Konno T, Kojima T, Kawano Y, Kobune M, Takada K. Gap junction beta-4 accelerates cell cycle progression and metastasis through MET-AKT activation in pancreatic cancer. Cancer Sci 2024; 115:1564-1575. [PMID: 38342100 PMCID: PMC11093205 DOI: 10.1111/cas.16101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 01/20/2024] [Accepted: 01/22/2024] [Indexed: 02/13/2024] Open
Abstract
Despite continuing advances in the development of effective new therapies, including immunotherapies, the prognosis of pancreatic cancer remains extremely poor. Gap junction proteins have become attractive targets for potential cancer therapy. However, the role of gap junction beta-4 (GJB4) protein remains unexplored in pancreatic cancer. Through bioinformatic analyses we discovered pancreatic cancer tissues showed higher levels of GJB4 transcripts compared to normal pancreatic tissues and this had a negative effect on overall survival in patients that had pancreatic cancer. The high expression of nuclear GJB4 was identified as a negative prognostic factor in such patients. Knockdown of GJB4 in cultured pancreatic cancer cells resulted in G0/G1 arrest followed by decreased cell proliferation and suppression of metastatic potential. The overexpression of GJB4 accelerated cell proliferation, migration, and invasion in a SUIT-2 cell line, whereas MET inhibitor canceled the acceleration. GJB4 suppression with siRNA significantly inhibited tumor growth in a mouse xenograft model. Mechanistically, suppression of GJB4 inhibited MET-AKT activities. Such data suggest that targeting the GJB4-MET axis could represent a promising new therapeutic strategy for pancreatic cancer.
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Affiliation(s)
- Joji Muramatsu
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Yohei Arihara
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Makoto Yoshida
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Tomohiro Kubo
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Hajime Nakamura
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Kazuma Ishikawa
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
| | - Hiromi Fujita
- Department of Surgical PathologySapporo Medical University School of MedicineSapporoJapan
| | - Shintaro Sugita
- Department of Surgical PathologySapporo Medical University School of MedicineSapporoJapan
| | - Takumi Konno
- Department of Cell Science, Research Institute for Frontiers MedicineSapporo Medical University School of MedicineSapporoJapan
| | - Takashi Kojima
- Department of Cell Science, Research Institute for Frontiers MedicineSapporo Medical University School of MedicineSapporoJapan
| | - Yutaka Kawano
- Department of Community Medicine and Medical ScienceTokushima University Graduate School of Biomedical SciencesTokushimaJapan
| | - Masayoshi Kobune
- Department of HematologySapporo Medical University School of MedicineSapporoJapan
| | - Kohichi Takada
- Department of Medical OncologySapporo Medical University School of MedicineSapporoJapan
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Hotz A, Fölster-Holst R, Oji V, Bourrat E, Frank J, Marrakchi S, Ennouri M, Wankner L, Komlosi K, Alter S, Fischer J. Erythrokeratodermia Variabilis-like Phenotype in Patients Carrying ABCA12 Mutations. Genes (Basel) 2024; 15:288. [PMID: 38540347 PMCID: PMC10970099 DOI: 10.3390/genes15030288] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 06/14/2024] Open
Abstract
Erythrokeratodermia variabilis (EKV) is a rare genodermatosis characterized by well-demarcated erythematous patches and hyperkeratotic plaques. EKV is most often transmitted in an autosomal dominant manner. Until recently, only mutations in connexins such as GJB3 (connexin 31), GJB4 (connexin 30.3), and occasionally GJA1 (connexin 43) were known to cause EKV. In recent years, mutations in other genes have been described as rare causes of EKV, including the genes KDSR, KRT83, and TRPM4. Features of the EKV phenotype can also appear with other genodermatoses: for example, in Netherton syndrome, which hampers correct diagnosis. However, in autosomal recessive congenital ichthyosis (ARCI), an EKV phenotype has rarely been described. Here, we report on seven patients who clinically show a clear EKV phenotype, but in whom molecular genetic analysis revealed biallelic mutations in ABCA12, which is why the patients are classified in the ARCI group. Our study indicates that ARCI should be considered as a differential diagnosis in EKV.
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Affiliation(s)
- Alrun Hotz
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Center for Cornification Disorders, Freiburg Center for Rare Diseases, Medical Center, University of Freiburg, 79106 Freiburg, Germany
- Institute of Human Genetics, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Regina Fölster-Holst
- Department of Dermatology, Venerology and Allergology, University Medical Center Schleswig-Holstein, 24105 Kiel, Germany;
| | - Vinzenz Oji
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Department of Dermatology and Venereology, Muenster University Medical Center, 48149 Muenster, Germany
| | - Emmanuelle Bourrat
- Department of Dermatology, Reference Center for Rare Skin Diseases MAGEC, Saint Louis Hospital AP-HP, 75015 Paris, France;
| | - Jorge Frank
- Department of Dermatology, Venereology and Allergology, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Slaheddine Marrakchi
- Department of Dermatology, CHU Hedi Chaker, Sfax University, Sfax 3029, Tunisia;
| | - Mariem Ennouri
- Laboratory of Molecular and Functional Genetics, Faculty of Sciences of Sfax, Sfax University, Sfax 3029, Tunisia;
| | - Lotta Wankner
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Center for Cornification Disorders, Freiburg Center for Rare Diseases, Medical Center, University of Freiburg, 79106 Freiburg, Germany
- Institute of Human Genetics, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Katalin Komlosi
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Center for Cornification Disorders, Freiburg Center for Rare Diseases, Medical Center, University of Freiburg, 79106 Freiburg, Germany
- Institute of Human Genetics, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Svenja Alter
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Center for Cornification Disorders, Freiburg Center for Rare Diseases, Medical Center, University of Freiburg, 79106 Freiburg, Germany
- Institute of Human Genetics, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Judith Fischer
- European Reference Networks (ERN Skin), 75015 Paris, France; (A.H.); (V.O.); (K.K.); (S.A.)
- Center for Cornification Disorders, Freiburg Center for Rare Diseases, Medical Center, University of Freiburg, 79106 Freiburg, Germany
- Institute of Human Genetics, Medical Center—University of Freiburg, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
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Plázár D, Meznerics FA, Pálla S, Anker P, Farkas K, Bánvölgyi A, Kiss N, Medvecz M. Dermoscopic Patterns of Genodermatoses: A Comprehensive Analysis. Biomedicines 2023; 11:2717. [PMID: 37893091 PMCID: PMC10604867 DOI: 10.3390/biomedicines11102717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 09/28/2023] [Accepted: 09/29/2023] [Indexed: 10/29/2023] Open
Abstract
(1) Background: Genodermatoses are a clinically and genetically heterogenous group of inherited skin disorders. Diagnosing inherited skin diseases is a challenging task due to their rarity and diversity. Dermoscopy is a non-invasive, easily accessible, and rapid tool used in dermatology not only for diagnostic processes but also for monitoring therapeutic responses. Standardized terminologies have been published for its proper use, reproducibility, and comparability of dermoscopic terms. (2) Methods: Here, we aimed to investigate dermoscopic features in various genodermatoses by conducting a systematic review and comparing its results to our own findings, data of patients diagnosed with genodermatoses at the Department of Dermatology, Venereology and Dermatooncology, Semmelweis University. (3) Results: Our systematic search provided a total of 471 articles, of which 83 reported both descriptive and metaphoric dermoscopic terminologies of 14 genodermatoses. The literature data were then compared to the data of 119 patients with 14 genodermatoses diagnosed in our department. (4) Conclusion: Dermoscopy is a valuable tool in the diagnosis of genodermatoses, especially when symptoms are mild. To enable the use of dermoscopy as an auxiliary diagnostic method, existing standardized terminologies should be extended to more genodermatoses.
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Affiliation(s)
| | | | | | | | | | | | | | - Márta Medvecz
- Department of Dermatology, Venereology and Dermatooncology, Faculty of Medicine, Semmelweis University, 1085 Budapest, Hungary; (D.P.); (F.A.M.); (S.P.); (P.A.); (K.F.); (A.B.); (N.K.)
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Zong YJ, Liu XZ, Tu L, Sun Y. Cytomembrane Trafficking Pathways of Connexin 26, 30, and 43. Int J Mol Sci 2023; 24:10349. [PMID: 37373495 DOI: 10.3390/ijms241210349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
The connexin gene family is the most prevalent gene that contributes to hearing loss. Connexins 26 and 30, encoded by GJB2 and GJB6, respectively, are the most abundantly expressed connexins in the inner ear. Connexin 43, which is encoded by GJA1, appears to be widely expressed in various organs, including the heart, skin, the brain, and the inner ear. The mutations that arise in GJB2, GJB6, and GJA1 can all result in comprehensive or non-comprehensive genetic deafness in newborns. As it is predicted that connexins include at least 20 isoforms in humans, the biosynthesis, structural composition, and degradation of connexins must be precisely regulated so that the gap junctions can properly operate. Certain mutations result in connexins possessing a faulty subcellular localization, failing to transport to the cell membrane and preventing gap junction formation, ultimately leading to connexin dysfunction and hearing loss. In this review, we provide a discussion of the transport models for connexin 43, connexins 30 and 26, mutations affecting trafficking pathways of these connexins, the existing controversies in the trafficking pathways of connexins, and the molecules involved in connexin trafficking and their functions. This review can contribute to a new way of understanding the etiological principles of connexin mutations and finding therapeutic strategies for hereditary deafness.
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Affiliation(s)
- Yan-Jun Zong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Xiao-Zhou Liu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Lei Tu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yu Sun
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Hubei Province Key Laboratory of Oral and Maxillofacial Development and Regeneration, Wuhan 430022, China
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Lucaciu SA, Figliuzzi R, Neumann R, Nazarali S, Del Sordo L, Leighton SE, Hauser A, Shao Q, Johnston D, Bai D, Laird DW. GJB4 variants linked to skin disease exhibit a trafficking deficiency en route to gap junction formation that can be restored by co-expression of select connexins. Front Cell Dev Biol 2023; 11:1073805. [PMID: 36861039 PMCID: PMC9968944 DOI: 10.3389/fcell.2023.1073805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 02/01/2023] [Indexed: 02/15/2023] Open
Abstract
Epidermal keratinocytes are enriched with at least nine connexins that are key regulators of epidermal homeostasis. The role of Cx30.3 in keratinocytes and epidermal health became evident when fourteen autosomal dominant mutations in the Cx30.3-encoding GJB4 gene were linked to a rare and incurable skin disorder called erythrokeratodermia variabilis et progressiva (EKVP). While these variants are linked to EKVP, they remain largely uncharacterized hindering therapeutic options. In this study, we characterize the expression and functional status of three EKVP-linked Cx30.3 mutants (G12D, T85P, and F189Y) in tissue-relevant and differentiation-competent rat epidermal keratinocytes. We found that GFP-tagged Cx30.3 mutants were non-functional likely due to their impaired trafficking and primary entrapment within the endoplasmic reticulum (ER). However, all mutants failed to increase BiP/GRP78 levels suggesting they were not inducing an unfolded protein response. FLAG-tagged Cx30.3 mutants were also trafficking impaired yet occasionally exhibited some capacity to assemble into gap junctions. The pathological impact of these mutants may extend beyond their trafficking deficiencies as keratinocytes expressing FLAG-tagged Cx30.3 mutants exhibited increased propidium iodide uptake in the absence of divalent cations. Attempts to rescue the delivery of trafficking impaired GFP-tagged Cx30.3 mutants into gap junctions by chemical chaperone treatment were ineffective. However, co-expression of wild type Cx30.3 greatly enhanced the assembly of Cx30.3 mutants into gap junctions, although endogenous levels of Cx30.3 do not appear to prevent the skin pathology found in patients harboring these autosomal dominant mutations. In addition, a spectrum of connexin isoforms (Cx26, Cx30, and Cx43) exhibited the differential ability to trans-dominantly rescue the assembly of GFP-tagged Cx30.3 mutants into gap junctions suggesting a broad range of connexins found in keratinocytes may favourably interact with Cx30.3 mutants. We conclude that selective upregulation of compatible wild type connexins in keratinocytes may have potential therapeutic value in rescuing epidermal defects invoked by Cx30.3 EKVP-linked mutants.
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Affiliation(s)
- Sergiu A. Lucaciu
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Rhett Figliuzzi
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Ruth Neumann
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Samina Nazarali
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Luigi Del Sordo
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Stephanie E. Leighton
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Alexandra Hauser
- 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
| | - Danielle Johnston
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada
| | - Donglin Bai
- Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada
| | - Dale W. Laird
- Department of Anatomy and Cell Biology, University of Western Ontario, London, ON, Canada,Department of Physiology and Pharmacology, University of Western Ontario, London, ON, Canada,*Correspondence: Dale W. Laird,
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Increased Hemichannel Activity Displayed by a Connexin43 Mutation Causing a Familial Connexinopathy Exhibiting Hypotrichosis with Follicular Keratosis and Hyperostosis. Int J Mol Sci 2023; 24:ijms24032222. [PMID: 36768546 PMCID: PMC9916973 DOI: 10.3390/ijms24032222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/26/2023] Open
Abstract
Mutations in the GJA1 gene that encodes connexin43 (Cx43) cause several rare genetic disorders, including diseases affecting the epidermis. Here, we examined the in vitro functional consequences of a Cx43 mutation, Cx43-G38E, linked to a novel human phenotype of hypotrichosis, follicular keratosis and hyperostosis. We found that Cx43-G38E was efficiently translated in Xenopus oocytes and localized to gap junction plaques in transfected HeLa cells. Cx43-G38E formed functional gap junction channels with the same efficiency as wild-type Cx43 in Xenopus oocytes, although voltage gating of the gap junction channels was altered. Notably, Cx43-G38E significantly increased membrane current flow through the formation of active hemichannels when compared to wild-type Cx43. These data demonstrate the association of increased hemichannel activity to a connexin mutation linked to a skeletal-cutaneous phenotype, suggesting that augmented hemichannel activity could play a role in skin and skeletal disorders caused by human Cx43 mutations.
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Gao Y, Zhang Q, Zhang S, Yang L, Liu Y, Liu Y, Wang T. A Connexin Gene (GJB3) Mutation in a Chinese Family With Erythrokeratodermia Variabilis, Ichthyosis and Nonsyndromic Hearing Loss: Case Report and Mutations Update. Front Genet 2022; 13:797124. [PMID: 35677558 PMCID: PMC9168653 DOI: 10.3389/fgene.2022.797124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 03/28/2022] [Indexed: 11/13/2022] Open
Abstract
Background: Gap junctions formed by connexins are channels on cytoplasm functioning in ion recycling and homeostasis. Some members of connexin family including connexin 31 are significant components in human skin and cochlea. In clinic, mutations of connexin 31 have been revealed as the cause of a rare hereditary skin disease called erythrokeratodermia variabilis (EKV) and non-syndromic hearing loss (NSHL).Objective: To determine the underlying genetic cause of EKV, ichthyosis and NSHL in three members of a Chinese pedigree and skin histologic characteristics of the EKV patient.Methods: By performing whole exome sequencing (WES), Sanger sequencing and skin biopsy, we demonstrate a Chinese pedigree carrying a mutation of GJB3 with three patients separately diagnosed with EKV, ichthyosis and NSHL.Results: The proband, a 6-year-old Chinese girl, presented with demarcated annular red-brown plaques and hyperkeratotic scaly patches on her trunk and limbs. Her mother has ichthyosis with hyperkeratosis and geographic tongue while her younger brother had NSHL since birth. Mutation analysis revealed all of them carried a heterozygous missense mutation c.293G>A of GJB3. Skin biopsy showed many grain cells with dyskeratosis in the granular layer. Acanthosis, papillomatosis, and a mild superficial perivascular lymphocytic infiltrate were observed.Conclusion: A mutation of GJB3 associated with EKV, ichthyosis and NSHL is reported in this case. The daughter with EKV and the son with NSHL in this Chinese family inherited the mutation from their mother with ichthyosis. The variation of clinical features may involve with genetic, epigenetic and environmental factors.
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Affiliation(s)
- Yajuan Gao
- State Key Laboratory of Complex Severe and Rare Diseases, Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China
| | - Qianli Zhang
- Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Shiyu Zhang
- State Key Laboratory of Complex Severe and Rare Diseases, Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China
| | - Lu Yang
- State Key Laboratory of Complex Severe and Rare Diseases, Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China
| | - Yaping Liu
- Department of Medical Genetics and National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- *Correspondence: Yaping Liu, ; Yuehua Liu, ; Tao Wang,
| | - Yuehua Liu
- State Key Laboratory of Complex Severe and Rare Diseases, Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China
- *Correspondence: Yaping Liu, ; Yuehua Liu, ; Tao Wang,
| | - Tao Wang
- State Key Laboratory of Complex Severe and Rare Diseases, Department of Dermatology, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, National Clinical Research Center for Dermatologic and Immunologic Diseases, Beijing, China
- *Correspondence: Yaping Liu, ; Yuehua Liu, ; Tao Wang,
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Dai Y, Zheng X, Zhang Q, Hu X, Wang P, Yang S. Case Report: Challenges in the Diagnosis of a Case of Mal de Meleda and a Therapeutic Attempt of Ixekizumab and Adalimumab. Front Med (Lausanne) 2022; 9:821301. [PMID: 35360724 PMCID: PMC8961326 DOI: 10.3389/fmed.2022.821301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 01/31/2022] [Indexed: 12/30/2022] Open
Abstract
Background Mal de Meleda (MDM, OMIM 248300) is an autosomal recessive disease characterized by symmetrical and progressive palmoplantar hyperkeratosis soon after birth. Mutations in SLURP1 gene could lead to MDM. Clinically, MDM is easily misdiagnosed as other types of keratoderma due to phenotypic variation and overlap. Objective and Methods A patient with suspected MDM was confirmed by the combination of next-generation sequencing and Exomiser, and the patient was attempted with the treatment of Ixekizumab and Adalimumab. Results A homozygous mutation c.256G>A (p.Gly86Arg) in the SLURP1 gene was identified in the patient. The inflammatory erythemas on his hands, feet and buttocks were mildly relieved after the treatment of high dose of Ixekizumab. Conclusions Our findings helps to enhance the understanding of MDM. Ixekizumab may be a potential strategy to treat MDM.
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Affiliation(s)
- Yuwei Dai
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China,Ferry Outpatient Department, The Ferry Skin Research Institute, Hefei, China
| | - Xiaodong Zheng
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China
| | - Qi Zhang
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China,Ferry Outpatient Department, The Ferry Skin Research Institute, Hefei, China
| | - Xia Hu
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China,Ferry Outpatient Department, The Ferry Skin Research Institute, Hefei, China
| | - Peiguang Wang
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China,*Correspondence: Peiguang Wang
| | - Sen Yang
- Department of Dermatology, The First Affiliated Hospital, Anhui Medical University, Hefei, China,Institute of Dermatology, Anhui Medical University, Hefei, China,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China,Provincial Laboratory of Inflammatory and Immune Mediated Diseases, Hefei, China,Ferry Outpatient Department, The Ferry Skin Research Institute, Hefei, China,Sen Yang
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Interrogation of Carboxy-Terminus Localized GJA1 Variants Associated with Erythrokeratodermia Variabilis et Progressiva. Int J Mol Sci 2022; 23:ijms23010486. [PMID: 35008913 PMCID: PMC8745721 DOI: 10.3390/ijms23010486] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 12/17/2021] [Accepted: 12/24/2021] [Indexed: 02/04/2023] Open
Abstract
Although inherited GJA1 (encoding Cx43) gene mutations most often lead to oculodentodigital dysplasia and related disorders, four variants have been linked to erythrokeratodermia variabilis et progressiva (EKVP), a skin disorder characterized by erythematous and hyperkeratotic lesions. While two autosomal-dominant EKVP-linked GJA1 mutations have been shown to lead to augmented hemichannels, the consequence(s) of keratinocytes harboring a de novo P283L variant alone or in combination with a de novo T290N variant remain unknown. Interestingly, these variants reside within or adjacent to a carboxy terminus polypeptide motif that has been shown to be important in regulating the internalization and degradation of Cx43. Cx43-rich rat epidermal keratinocytes (REKs) or Cx43-ablated REKs engineered to express fluorescent protein-tagged P283L and/or T290N variants formed prototypical gap junctions at cell-cell interfaces similar to wildtype Cx43. Dye coupling and dye uptake studies further revealed that each variant or a combination of both variants formed functional gap junction channels, with no evidence of augmented hemichannel function or induction of cell death. Tracking the fate of EKVP-associated variants in the presence of the protein secretion blocker brefeldin A, or an inhibitor of protein synthesis cycloheximide, revealed that P283L or the combination of P283L and T290N variants either significantly extended Cx43 residency on the cell surface of keratinocytes or delayed its degradation. However, caution is needed in concluding that this modest change in the Cx43 life cycle is sufficient to cause EKVP, or whether an additional underlying mechanism or another unidentified gene mutation is contributing to the pathogenesis found in patients. This question will be resolved if further patients are identified where whole exome sequencing reveals a Cx43 P283L variant alone or, in combination with a T290N variant, co-segregates with EKVP across several family generations.
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11
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Laird DW, Lampe PD. Cellular mechanisms of connexin-based inherited diseases. Trends Cell Biol 2022; 32:58-69. [PMID: 34429228 PMCID: PMC8688313 DOI: 10.1016/j.tcb.2021.07.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 01/03/2023]
Abstract
The 21-member connexin gene family exhibits distinct tissue expression patterns that can cause a diverse array of over 30 inherited connexin-linked diseases ranging from deafness to skin defects and blindness. Intriguingly, germline mutations can cause disease in one tissue while other tissues that abundantly express the mutant connexin remain disease free, highlighting the importance of the cellular context of mutant expression. Modeling connexin pathologies in genetically modified mice and tissue-relevant cells has informed extensively on no less than a dozen gain- and loss-of-function mechanisms that underpin disease. This review focuses on how a deeper molecular understanding of the over 930 mutations in 11 connexin-encoding genes is foundational for creating a framework for therapeutic interventions.
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Affiliation(s)
- Dale W. Laird
- Departments of Anatomy and Cell Biology, and Physiology and Pharmacology, University of Western Ontario, London, ON, CANADA
| | - Paul D. Lampe
- Translational Research Program, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
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12
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Charfeddine C, Laroussi N, Mkaouar R, Jouini R, Khayat O, Redissi A, Mosbah A, Dallali H, Chedly Debbiche A, Zaouak A, Fenniche S, Abdelhak S, Hammami-Ghorbel H. Expanding the clinical phenotype associated with NIPAL4 mutation: Study of a Tunisian consanguineous family with erythrokeratodermia variabilis-Like Autosomal Recessive Congenital Ichthyosis. PLoS One 2021; 16:e0258777. [PMID: 34669720 PMCID: PMC8528321 DOI: 10.1371/journal.pone.0258777] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 10/05/2021] [Indexed: 11/19/2022] Open
Abstract
Erythrokeratodermia variabilis (EKV) is a rare disorder of cornification usually associated with dominant mutations in the GJB3 and GJB4 genes encoding connexins (Cx)31 and 30.3. Genetic heterogeneity of EKV has already been suggested. We investigated at the clinical and genetic level a consanguineous Tunisian family with 2 sisters presenting an autosomal recessive form of EKV to better characterize this disease. Mutational analysis initially screened the connexin genes and Whole-exome sequencing (WES) was performed to identify the molecular aetiology of the particular EKV phenotype in the proband. Migratory shaped erythematous areas are the initial presenting sign followed by relatively stable hyperkeratotic plaques are the two predominates characteristics in both patients. However, remarkable variability of morphological and dominating features of the disease were observed between patients. In particular, the younger sister (proband) exhibited ichthyosiform-like appearance suggesting Autosomal Recessive Congenital Ichthyosis (ARCI) condition. No causative mutations were detected in the GJB3 and GJB4 genes. WES results revealed a novel missense homozygous mutation in NIPAL4 gene (c.835C>G, p.Pro279Ala) in both patients. This variant is predicted to be likely pathogenic. In addition, in silico analysis of the mutated 3D domain structure predicted that this variant would result in NIPA4 protein destabilization and Mg2+ transport perturbation, pointing out the potential role of NIPAL4 gene in the development and maintenance of the barrier function of the epidermis. Taken togheter, these results expand the clinical phenotype associated with NIPAL4 mutation and reinforce our hypothesis of NIPAL4 as the main candidate gene for the EKV-like ARCI phenotype.
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Affiliation(s)
- Cherine Charfeddine
- University Tunis El Manar, Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, LR20IPT05, Tunis, Tunisia
- Université de la Manouba, Institut de Biotechnologie de Sidi Thabet, Ariana, Tunisia
- * E-mail:
| | - Nadia Laroussi
- University Tunis El Manar, Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, LR20IPT05, Tunis, Tunisia
| | - Rahma Mkaouar
- University Tunis El Manar, Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, LR20IPT05, Tunis, Tunisia
| | - Raja Jouini
- Department of Pathology, Habib Thameur Hospital, Tunis, Tunisia
| | - Olfa Khayat
- Department of Pathology, Habib Thameur Hospital, Tunis, Tunisia
| | - Aladin Redissi
- BVBGR-LR11ES31, ISBST, Université de la Manouba, Institut de Biotechnologie de Sidi Thabet, Ariana, Tunisia
| | - Amor Mosbah
- BVBGR-LR11ES31, ISBST, Université de la Manouba, Institut de Biotechnologie de Sidi Thabet, Ariana, Tunisia
| | - Hamza Dallali
- University Tunis El Manar, Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, LR20IPT05, Tunis, Tunisia
| | | | - Anissa Zaouak
- Department of Dermatology, Genodermatosis and Cancers Laboratory LR12SP03, Habib Thameur Hospital, Tunis, Tunisia
| | - Sami Fenniche
- Department of Dermatology, Genodermatosis and Cancers Laboratory LR12SP03, Habib Thameur Hospital, Tunis, Tunisia
| | - Sonia Abdelhak
- University Tunis El Manar, Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, LR20IPT05, Tunis, Tunisia
| | - Houda Hammami-Ghorbel
- Department of Dermatology, Genodermatosis and Cancers Laboratory LR12SP03, Habib Thameur Hospital, Tunis, Tunisia
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13
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Au A, Shao Q, White KK, Lucaciu SA, Esseltine JL, Barr K, Laird DW. Comparative Analysis of Cx31 and Cx43 in Differentiation-Competent Rodent Keratinocytes. Biomolecules 2020; 10:biom10101443. [PMID: 33066499 PMCID: PMC7602205 DOI: 10.3390/biom10101443] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/30/2020] [Accepted: 10/08/2020] [Indexed: 12/25/2022] Open
Abstract
When considering connexin expression and regulation, the epidermis of the skin is one of the most complex tissues found in mammals even though it largely contains a single cell type, the keratinocyte. In the rodent epidermis, up to 9 connexin family members have been detected at the mRNA level. Many of these connexins are temporally and spatially regulated in coordination with keratinocyte progenitor cell differentiation and migration from the stratum basale to form the stratum spinosum and stratum granulosum layers before finally forming the stratum corneum. Cx43 is the principal connexin found in basal keratinocytes and to a lesser degree found in keratinocytes that have begun to differentiate where Cx26, Cx30 and Cx31 become prevalent. Here we show that the CRISPR-Cas9 ablation of Cx43 reduces overall gap junction coupling in monolayer cultures of rat epidermal keratinocytes (REKs) and dysregulates the differentiation of REKs when grown in organotypic cultures. Natively found in differentiated keratinocytes, Cx31 readily assembles into gap junctions when expressed in REKs where it can extensively co-assemble into the same gap junctions with co-expressed Cx30. Time-lapse imaging indicated that many Cx31 gap junctions are mobile within the plasma membrane undergoing both fusion and fission events. Finally, the persistence of pre-existing Cx31 gap junctions in the presence of the protein trafficking blocker, brefeldin A, is longer than that found for Cx43 gap junctions indicating that it has a distinctly different life expectancy in REKs. Collectively, this study highlights the importance of Cx43 in rodent keratinocyte differentiation and suggests that Cx31 acquires life-cycle properties that are distinct from Cx43.
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Affiliation(s)
- Akina Au
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (A.A.); (S.A.L.)
| | - Qing Shao
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada; (Q.S.); (K.K.W.); (K.B.)
| | - Kyra K. White
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada; (Q.S.); (K.K.W.); (K.B.)
| | - Sergiu A. Lucaciu
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (A.A.); (S.A.L.)
| | - Jessica L. Esseltine
- Division of BioMedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6, Canada;
| | - Kevin Barr
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada; (Q.S.); (K.K.W.); (K.B.)
| | - Dale W. Laird
- Department of Physiology and Pharmacology, The University of Western Ontario, London, ON N6A 5C1, Canada; (A.A.); (S.A.L.)
- Department of Anatomy and Cell Biology, The University of Western Ontario, London, ON N6A 5C1, Canada; (Q.S.); (K.K.W.); (K.B.)
- Correspondence: ; Tel.: +1-519-661-2111 (ext. 86827)
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14
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de Oliveira RTG, Christofolini DM, Criado PR, Lacaz Martins E, Kelsell D, Machado Filho CDS. Clinical variability of the GJB4:c.35G > A gene variant: a study of a large Brazilian erythrokeratodermia pedigree. Int J Dermatol 2020; 59:722-725. [PMID: 32311086 DOI: 10.1111/ijd.14894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/07/2020] [Accepted: 03/26/2020] [Indexed: 11/29/2022]
Abstract
BACKGROUND Erythrokeratodermas are a heterogeneous group of keratinization disorders. They are inherited in both autosomal dominant and autosomal recessive pattern. Erythrokeratoderma variabilis et progressive (EKVP) is a disorder caused by variations in genes that codify connexins (GJA1, GJB3, GJB4). The distinction between different phenotypes is not always simple. Age of presentation varies from birth to adulthood; stationary or migratory erythematous plaques associated with nonmigratory hyperkeratosis are characteristic of this disorder. Nails, hair, and teeth are not affected. METHODS In order to describe the clinical phenotypes and molecular findings in a large Brazilian pedigree affected by erythrokeratoderma, we performed a clinical evaluation of four patients with different presentations of erythrokeratoderma from the same family, in which there are 35 affected members distributed in six generations. Genomic DNA evaluation by Sanger sequencing of GJB3 and GJB4 was performed in two affected family members with different phenotypes. RESULTS Clinical heterogeneity in affected patients was remarkable. In patients investigated with genetic testing, a heterozygous pathogenic gene variant in the GJB4 (gap junction protein beta-4) gene was found positive for GJB4:c.35G>A (rsrs80358211). One patient also presented a synonymous variant in GJB3:c.357C>T (rs41310442). CONCLUSION Variants in GJB4 are classically associated with Erythrokeratodermia variabilis, but there is remarkable clinical heterogeneity. Our observation that the same variant caused different phenotypes within the same family corroborates clinical heterogeneity and suggests that other genes that compose the genetic background exert some influence on the disease phenotype.
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Affiliation(s)
| | - Denise Maria Christofolini
- Department of Reproductive Health and Populational Genetics, Faculdade de Medicina do ABC, Santo André, SP, Brazil
| | - Paulo R Criado
- Department of Dermatology, Faculdade de Medicina do ABC, Santo André, SP, Brazil
| | | | - David Kelsell
- Barts and The London School of Medicine and Dentistry, Blizard Institute, Queen Mary University of London, London, UK
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15
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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] [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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16
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Connexin43 mutations linked to skin disease have augmented hemichannel activity. Sci Rep 2019; 9:19. [PMID: 30631135 PMCID: PMC6328547 DOI: 10.1038/s41598-018-37221-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 12/04/2018] [Indexed: 01/22/2023] Open
Abstract
Mutations in the gene (GJA1) encoding connexin43 (Cx43) are responsible for several rare genetic disorders, including non-syndromic skin-limited diseases. Here we used two different functional expression systems to characterize three Cx43 mutations linked to palmoplantar keratoderma and congenital alopecia-1, erythrokeratodermia variabilis et progressiva, or inflammatory linear verrucous epidermal nevus. In HeLa cells and Xenopus oocytes, we show that Cx43-G8V, Cx43-A44V and Cx43-E227D all formed functional gap junction channels with the same efficiency as wild-type Cx43, with normal voltage gating and a unitary conductance of ~110 pS. In HeLa cells, all three mutations also localized to regions of cell-cell contact and displayed a punctate staining pattern. In addition, we show that Cx43-G8V, Cx43-A44V and Cx43-E227D significantly increase membrane current flow through formation of active hemichannels, a novel activity that was not displayed by wild-type Cx43. The increased membrane current was inhibited by either 2 mM calcium, or 5 µM gadolinium, mediated by hemichannels with a unitary conductance of ~250 pS, and was not due to elevated mutant protein expression. The three Cx43 mutations all showed the same gain of function activity, suggesting that augmented hemichannel activity could play a role in skin-limited diseases caused by human Cx43 mutations.
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17
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A heterozygous mutation in GJA1 gene in Chinese family with serious erythrokeratodermia variabilis et progressive. Chin Med J (Engl) 2019; 132:86-88. [PMID: 30628963 PMCID: PMC6629316 DOI: 10.1097/cm9.0000000000000011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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18
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Oh DY, Jung KE, Lee JS, Koo DW. A Case of Erythrokeratodermia Variabilis in Korean. Ann Dermatol 2019; 31:S49-S51. [PMID: 33911695 PMCID: PMC7997078 DOI: 10.5021/ad.2019.31.s.s49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/02/2019] [Accepted: 03/25/2019] [Indexed: 11/18/2022] Open
Affiliation(s)
- Dae Young Oh
- Department of Dermatology, Eulji University Hospital, Eulji University School of Medicine, Daejeon, Korea
| | - Kyung Eun Jung
- Department of Dermatology, Eulji University Hospital, Eulji University School of Medicine, Daejeon, Korea
| | - Joong Sun Lee
- Department of Dermatology, Eulji University Hospital, Eulji University School of Medicine, Daejeon, Korea
| | - Dae Won Koo
- Department of Dermatology, Eulji University Hospital, Eulji University School of Medicine, Daejeon, Korea
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19
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Gain-of-Function Mutations in TRPM4 Activation Gate Cause Progressive Symmetric Erythrokeratodermia. J Invest Dermatol 2018; 139:1089-1097. [PMID: 30528822 DOI: 10.1016/j.jid.2018.10.044] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 09/27/2018] [Accepted: 10/03/2018] [Indexed: 01/12/2023]
Abstract
Transient receptor potential (TRP) channels respond to various chemical and physical stimuli by mediating cation influx. The skin expresses abundant TRP channels of different subtypes, which play an essential role in the maintenance of skin functionality. Here, we report cases of mutations in TRPM4, which encodes TRPM4, a Ca2+-activated monovalent cation channel, as a cause of an autosomal dominant form of progressive symmetric erythrokeratodermia. In three separate families with progressive symmetric erythrokeratodermia, we identified two missense mutations (c.3099C>G and c.3119T>C) that produce p.Ile1033Met and p.Ile1040Thr, both of which are located in the S6 transmembrane domain of the TRPM4 protein. The substitutions are expected to directly affect activation gating of TRPM4 according to the cryo-EM structures. Electrophysiological studies of the mutants showed substantial hyperactivity, as evidenced by pronounced baseline activity, enhanced sensitivity to intracellular Ca2+, and an elevated resting membrane potential. In vitro studies showed enhanced proliferation in keratinocytes overexpressing either of the mutants. We also detected an up-regulation of markers for proliferation and differentiation of keratinocytes in the affected skin tissues. Our study identified TRPM4 as an important player in the pathogenesis of skin TRP channelopathies and a potential target for treatment of skin hyperkeratotic disorders.
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20
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Bourque PR, Warman-Chardon J, Lelli DA, LaBerge L, Kirshen C, Bradshaw SH, Hartley T, Boycott KM. Novel ELOVL4 mutation associated with erythrokeratodermia and spinocerebellar ataxia (SCA 34). NEUROLOGY-GENETICS 2018; 4:e263. [PMID: 30065956 PMCID: PMC6066365 DOI: 10.1212/nxg.0000000000000263] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/07/2018] [Indexed: 11/15/2022]
Affiliation(s)
- Pierre R Bourque
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Jodi Warman-Chardon
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Daniel A Lelli
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Lauren LaBerge
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Carly Kirshen
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Scott H Bradshaw
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Taila Hartley
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
| | - Kym M Boycott
- Department of Medicine (Neurology) (P.R.B., J.W-C., D.A.L.), University of Ottawa; Ottawa Hospital Research Institute (P.R.B., J.W-C.); Department of Medicine (Dermatology) (L.L., C.K.), University of Ottawa; Department of Anatomical Pathology (S.H.B.), University of Ottawa; and Department of Genetics (J.W-C., T.H., K.M.B.), Children's Hospital of Eastern Ontario, Ottawa, Canada
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21
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Deng Y, Wang H, Mou Y, Zeng Q, Xiong X. Exome sequencing identifies novel compound heterozygous mutations in GJB3 gene that cause erythrokeratodermia variabilis et progressiva. Australas J Dermatol 2018; 60:e87-e89. [PMID: 29992552 PMCID: PMC6585696 DOI: 10.1111/ajd.12887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yongqiong Deng
- Department of Dermatology & STD, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Hong Wang
- Department of Dermatology & STD, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Yunzhu Mou
- Department of Dermatology & STD, Affiliated Hospital of North Sichuan Medical College, Nanchong, Sichuan, China
| | - Qi Zeng
- Pediatric Department, Peking University First Hospital, Beijing, China
| | - Xia Xiong
- Department of Dermatology & STD, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
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22
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Onnis G, Bourrat E, Jonca N, Dreyfus I, Severino-Freire M, Pichery M, Fischer J, Mazereeuw-Hautier J. KLICK syndrome: an unusual phenotype. Br J Dermatol 2018; 178:1445-1446. [PMID: 29315485 DOI: 10.1111/bjd.16318] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- G Onnis
- Reference Centre for Rare Skin Diseases, Dermatology Department, CHU Larrey, Paul Sabatier University, Toulouse, France
| | - E Bourrat
- Department of Dermatology, Reference Centre for Rare Skin Diseases, MAGEC Saint Louis Hospital, APHP, Paris, France
| | - N Jonca
- Epithelial Differentiation Unity and Autoimmunity Rheumatological (NEAR), University of Toulouse, Toulouse, France
| | - I Dreyfus
- Reference Centre for Rare Skin Diseases, Dermatology Department, CHU Larrey, Paul Sabatier University, Toulouse, France
| | - M Severino-Freire
- Reference Centre for Rare Skin Diseases, Dermatology Department, CHU Larrey, Paul Sabatier University, Toulouse, France.,Epithelial Differentiation Unity and Autoimmunity Rheumatological (NEAR), University of Toulouse, Toulouse, France
| | - M Pichery
- Unité Différenciation Epithéliale et Autoimmunité Rhumatoïde (UDEAR), UMR 1056 Inserm - Université de Toulouse, Hôpital Purpan, Toulouse, France
| | - J Fischer
- Institute of Human Genetics, University Medical Center Freiburg, Freiburg, Germany
| | - J Mazereeuw-Hautier
- Reference Centre for Rare Skin Diseases, Dermatology Department, CHU Larrey, Paul Sabatier University, Toulouse, France.,Epithelial Differentiation Unity and Autoimmunity Rheumatological (NEAR), University of Toulouse, Toulouse, France
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Srinivas M, Verselis VK, White TW. Human diseases associated with connexin mutations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1860:192-201. [PMID: 28457858 DOI: 10.1016/j.bbamem.2017.04.024] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [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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Umegaki-Arao N, Sasaki T, Fujita H, Aoki S, Kameyama K, Amagai M, Seishima M, Kubo A. Inflammatory Linear Verrucous Epidermal Nevus with a Postzygotic GJA1 Mutation Is a Mosaic Erythrokeratodermia Variabilis et Progressiva. J Invest Dermatol 2017; 137:967-970. [DOI: 10.1016/j.jid.2016.11.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/25/2016] [Accepted: 11/09/2016] [Indexed: 11/30/2022]
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