1
|
Li P, Qi J, Zhong Y, Ding A, Xiao H. Proteomic profiling reveals KRT6C as a probable hereterodimer partner for KRT9: New insights into re-classifying epidermolytic palmoplantar keratoderma (EPPK) and a milder form of pachyonychia congenita (PC-K6c) as a group of genetic cutaneous disorders. J Proteomics 2023; 287:104971. [PMID: 37467889 DOI: 10.1016/j.jprot.2023.104971] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 05/01/2023] [Accepted: 07/05/2023] [Indexed: 07/21/2023]
Abstract
Epidermolytic palmoplantar keratoderma (EPPK), a highly penetrant autosomal dominant genodermatosis, is characterized by diffuse keratoses on palmplantar epidermis. The keratin 9 gene (KRT9) is responsible for EPPK. To date, phenotypic therapy is the primary treatment for EPPK. Because KRT9 pairs with a type II keratin-binding partner to function in epidermis, identifying the interaction partner is an essential first step in revealing EPPK pathogenesis and its fundamental treatment. In this study, we proved that keratin 6C (KRT6C) is a probable hereterodimer partner for KRT9. In silico model for KRT6C/KRT9 shows a typical coiled-coil structure in their 2B domains. Proteomics analysis shows that KRT6C/KRT9 pair is in a densely connected protein-protein interaction network, where proteins participate jointly in regulating cytoskeleton organization and keratinization. This study shows that co-immunoprecipitation coupled with mass spectroscopy and proteomics analysis provide a sensitive approach, which compensates for inevitable inadequacies of anti-keratin 6C antibody and helps discover the probable hereterodimer partner KRT6C for KRT9. The acknowledgement of KRT6C/KRT9 pairwise relationship may help re-classify EPPK and PC-K6c (a milder form of pachyonychia congenita, caused by KRT6C) as a group of hereditary defects at a molecular-based level, and lay foundation for deciphering the keratin network contributing to EPPK and PC-K6c. SIGNIFICANCE OF THE STUDY: What is already known about this topic? KRT9 and KRT6C are disease-causing factors for epidermolytic palmoplantar keratoderma (EPPK) and a milder form of pachyonychia congenita (PC-K6c), respectively. EPPK and PC-K6c have some symptom similarities. Keratins are the major structural proteins in epithelial cells. Each of the type I keratin is matched by a particular type II keratin to assemble a coiled-coil heterodimer. The hereterodimer partner for KRT9 is unknown. What does this study add? We discovered and proved that KRT6C is a probable hereterodimer partner for KRT9 in palmplantar epidermis in a native endogenous environment by using co-immunoprecipitation coupled with mass spectroscopy and proteomics analysis, etc. The proteomics analysis shows that KRT6C/KRT9 keratin pair is in a densely connected protein-protein interaction network, where proteins participate jointly in regulating intermediate filament-based cytoskeleton organization and keratinization processes. What are the implications of this work? The new understanding of probable KRT6C/KRT9 pairwise correlation may help re-classify the genetic cutaneous disorders EPPK and PC-K6c as a group of hereditary defects at a molecular-based level, and lay foundation for pathogenic mechanism research in EPPK and PC-K6c. The densely related network components derived from the proteomic data using Metascape in the study and pairwise regulation fashion of specific keratin pairs should attract more attention in the further explorations when investigators concern the physiological functions of keratins and the pathogenesis of related skin diseases.
Collapse
Affiliation(s)
- Peiyao Li
- Key Laboratory of Carcinogenesis and Cancer Invasion of Ministry of Education, China NHC Key Laboratory of Carcinogenesis, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Jialin Qi
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, Hunan, People's Republic of China
| | - Yuhui Zhong
- Department of Pathology, School of Medicine, Hunan Normal University, Changsha, Hunan, People's Republic of China
| | - Aoli Ding
- Department of Pathology, School of Medicine, Hunan Normal University, Changsha, Hunan, People's Republic of China
| | - Heng Xiao
- Department of Pathology, School of Medicine, Hunan Normal University, Changsha, Hunan, People's Republic of China.
| |
Collapse
|
2
|
Li C, Chen P, Sun S, Zeng K, Liang J, Wang Q, Zhang S, Xu M, Li Z, Zhang X. Exome sequencing identifies a KRT9 pathogenic variant in a Chinese pedigree with epidermolytic palmoplantar keratoderma. Mol Genet Genomic Med 2019; 7:e00703. [PMID: 31074163 PMCID: PMC6625362 DOI: 10.1002/mgg3.703] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 03/16/2019] [Accepted: 04/08/2019] [Indexed: 12/15/2022] Open
Abstract
Background Epidermolytic palmoplantar keratoderma (EPPK) is a rare skin disorder and its pathogenesis and inheritability are unknown. Objective To investigate the inheritance and pathogenesis of EPPK. Methods Two EPPK cases occurred in a three‐generation Chinese family. Patient–parents trio EPPK was carried out and the identified candidate variants were confirmed by Sanger sequencing. Results A heterozygous missense pathogenic variant, c.488G > A (p.Arg163Gln), in the keratin (KRT) 9 gene was detected in the proband and his son via targeted exome sequencing, and then validated by Sanger sequencing. This pathogenic variant cosegregated with the EPPK in extended family members, and was predicted to be pathogenic by SIFT, PolyPhen2, PROVEAN, and Mutation Taster. This heterozygous variation was not evident in 100 healthy controls. Conclusion This report describes a KRT9 c.488G > A (p.Arg163Gln) variant causing a diffuse phenotype of Chinese EPPK. The current results broaden the spectrum of KRT9 pathogenic variants responsible for EPPK and have important implications for molecular diagnosis, treatment, and genetic counseling for this family.
Collapse
Affiliation(s)
- Changxing Li
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Pingjiao Chen
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Silong Sun
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | - Kang Zeng
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jingyao Liang
- Department of Dermatology, Guangzhou Institute of Dermatology, Guangzhou, China
| | - Qi Wang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Sanquan Zhang
- Department of Dermatology, Guangzhou Institute of Dermatology, Guangzhou, China
| | - Meinian Xu
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhijia Li
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Xibao Zhang
- Department of Dermatology, Guangzhou Institute of Dermatology, Guangzhou, China
| |
Collapse
|
3
|
Li Y, Tang L, Han Y, Zheng L, Zhen Q, Yang S, Gao M. Genetic Analysis of KRT9 Gene Revealed Previously Known Mutations and Genotype-Phenotype Correlations in Epidermolytic Palmoplantar Keratoderma. Front Genet 2019; 9:645. [PMID: 30666268 PMCID: PMC6330350 DOI: 10.3389/fgene.2018.00645] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 11/29/2018] [Indexed: 11/13/2022] Open
Abstract
Epidermolytic palmoplantar keratoderma (EPPK, OMIM 144200) is an autosomal dominant inherited disease, clinically characterized by diffuse yellowish thickening of the skin on the palms and soles, usually with erythematous borders developing during the first weeks or months after birth. Pathogenesis of EPPK is determined by mutations in the keratin gene (KRT9). Thirty three mutations in the KRT9 gene from 100 EPPK families have been identified. Among these, 23 mutations are located in the 1A region (a mutation hot spot region), 7 are located in the 2B region, and the remaining 3 are synonymous mutations. In this study, three heterozygous mutations (p.N161S, p.R163W, and p.R163Q), located in regions of the gene encoding the conserved central a-helix rod domain, were detected in the KRT9 gene of the three large Chinese families. This study confirms that codon 163 (48 of 100 cases) is a hot spot mutation site for KRT9. Additional findings identified p.N161S (4%) and p.R163W (4%) as potential hot spot mutations for EPPK associated with knuckle pads, and p.R163Q (15 of 100 cases) as the hot spot mutation of EPPK not occurring in combination with knuckle pads. In conjunction with future studies, this research may help lay the foundation for genetics counseling, prenatal diagnosis and clinical treatment of EPPK.
Collapse
Affiliation(s)
- Yuwei Li
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Lili Tang
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Yang Han
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Liyun Zheng
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Qi Zhen
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China.,Key Laboratory of Dermatology, Ministry of Education, Anhui Medical University, Hefei, China
| | - Sen Yang
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China
| | - Min Gao
- Institute of Dermatology and Department of Dermatology of First Affiliated Hospital, Hefei, China
| |
Collapse
|
4
|
Liang YH, Liu QX, Huang L, Zeng K. A recurrent p.M157R mutation of keratin 9 gene in a Chinese family with epidermolytic palmoplantar keratoderma and literature review. Int J Dermatol 2014; 53:e375-9. [PMID: 24899405 DOI: 10.1111/ijd.12352] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Yanhua H Liang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, 510515, China.
| | | | | | | |
Collapse
|
5
|
Lopez-Valdez J, Rivera-Vega MR, Gonzalez-Huerta LM, Cazarin J, Cuevas-Covarrubias S. Analysis of the KRT9 gene in a Mexican family with epidermolytic palmoplantar keratoderma. Pediatr Dermatol 2013; 30:354-8. [PMID: 23278372 DOI: 10.1111/pde.12027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epidermolytic palmoplantar keratoderma (EPPK), an autosomal-dominant genodermatosis, is the most frequently occurring hereditary palmoplantar keratoderma. EPPK is characterized by hyperkeratosis of the palms and soles. Approximately 90% of patients present with mutations in the KRT9 gene, which encodes for keratin 9. Many of these mutations are located within the highly conserved coil 1A region of the alpha-helical rod domain of keratin 9, an important domain for keratin heterodimerization. The objective was to assess the clinical and molecular characteristics of a Mexican family with EPPK. The clinical characteristics of members of this family were analyzed. The KRT9 gene of affected members was polymerase chain reaction amplified from genomic DNA and sequenced. All affected members of the family had hyperkeratosis of the palms and soles with knuckle pads. The R163W mutation in the KRT9 gene was present in all affected individuals who were tested. Although R163W is the most frequent KRT9 mutation in patients with EPPK, only two families have been reported with knuckle pads associated with this mutation. Our findings indicate that knuckle pads can be associated with EPPK and the R163W mutation in a family with a genetic background different from that described here.
Collapse
Affiliation(s)
- Jaime Lopez-Valdez
- Servicio de Genética, Hospital General de México, Facultad de Medicina, Universidad Nacional Autónoma de México, México City, DF, México
| | | | | | | | | |
Collapse
|
6
|
Kon A, Itagaki K, Yoneda K, Takagaki K. A novel mutation of keratin 9 gene (R162P) in a Japanese family with epidermolytic palmoplantar keratoderma. Arch Dermatol Res 2004; 296:375-8. [PMID: 15605275 DOI: 10.1007/s00403-004-0534-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2004] [Accepted: 11/22/2004] [Indexed: 11/29/2022]
Abstract
Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant inherited skin disorder characterized by hyperkeratosis of the skin over the palms and soles. Mutations in keratin 9 gene (KRT9) have been demonstrated in EPPK. In this study, we screened a Japanese family with EPPK for KRT9 mutation by polymerase chain reaction amplification of genomic sequences, followed by heteroduplex analysis and direct nucleotide sequencing. The mutation consisted of a G-to-C transversion at codon 162 in exon 1, which was located in the hot spot of the mutations that have been reported previously (R162Q and R162W). However, the amino acid substitution was proline for arginine (R162P) in the 1A rod domain, the highly conserved helix initiation motif of keratin 9. Our result illustrates the repertoire of KRT9 mutation underlying the occurrence of EPPK in a Japanese family and is an important contribution to the investigation of the genotype/phenotype correlation.
Collapse
Affiliation(s)
- Atsushi Kon
- Department of Biochemistry, Hirosaki University School of Medicine, 5 Zaifu-cho, Hirosaki, Aomori, 036-8562, Japan.
| | | | | | | |
Collapse
|
7
|
He XH, Zhang XN, Mao W, Chen HP, Xu LR, Chen H, He XL, Le YP. A novel mutation of keratin 9 in a large Chinese family with epidermolytic palmoplantar keratoderma. Br J Dermatol 2004; 150:647-51. [PMID: 15099359 DOI: 10.1111/j.0007-0963.2004.05865.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Epidermolytic palmoplantar keratoderma (EPPK) is an autosomal dominant inherited skin disorder characterized by diffuse yellow thickening of the skin of the palms and soles, sharply bordered with erythematous margins. Histologically and ultrastructurally, EPPK presents cytolysis of keratinocytes and abnormal aggregation of tonofilaments in the suprabasal layers of the epidermis. To date, 15 different mutations of the keratin 9 gene (KRT9) have been demonstrated to cause most cases of EPPK. OBJECTIVES To identify the KRT9 mutation in a large Chinese family with EPPK. METHODS Denaturing high-performance liquid chromatography (DHPLC), DNA sequencing and allele-specific polymerase chain reaction (AS-PCR) were used to screen exon 1 of the KRT9 gene for sequence variations. RESULTS The DHPLC elution profiles of the DNA fragments amplified from the affected samples differed from those obtained from unaffected individuals, indicating that a sequence variation existed within the analysed fragment of KRT9. DNA sequencing revealed a novel insertion-deletion mutation in the exon 1 of KRT9, 497delAinsGGCT, resulting in the change of tyrosine(166) to tryptophan and leucine (Y166delinsWL). AS-PCR confirmed the mutation was not a common polymorphism. CONCLUSIONS The results suggest the molecular basis of EPPK in this Chinese family and provide further evidence that mutations in the helix initiation motif of keratin 9 underlie Chinese EPPK.
Collapse
Affiliation(s)
- X-H He
- Department of Genetics, School of Medicine, Ningbo University, Ningbo, Zhejiang Province, 315211, China
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Kimyai-Asadi A, Kotcher LB, Jih MH. The molecular basis of hereditary palmoplantar keratodermas. J Am Acad Dermatol 2002; 47:327-43; quiz 344-6. [PMID: 12196741 DOI: 10.1067/mjd.2002.124814] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In recent years, the gene defects causing many types of hereditary palmoplantar keratoderma have been discovered. These genes encode a variety of proteins involved in the terminal differentiation of keratinocytes and the formation of the cornified cell envelope. In this article, we review the molecular defects underlying various palmoplantar keratodermas with particular attention to the role of these molecules in the terminal differentiation of palmoplantar epidermis. Of the proteins involved in keratodermas, loricrin, keratins, and desmosomal proteins provide the protein structure of the cornified cell envelope. Connexins form intercellular gap junctions, which regulate ionic calcium signals necessary for the expression of the proteins that form the cornified cell envelope. Cathepsins likely mediate enzymatic processes necessary for the formation and dissolution of the cornified cell envelope. The clinical phenotypes produced by various mutations affecting these proteins are discussed vis-à-vis data from genetic, cellular, and molecular experiments.
Collapse
Affiliation(s)
- Arash Kimyai-Asadi
- Ronald O. Perelman Department of Dermatology, The New York University School of Medicine, New York, USA
| | | | | |
Collapse
|
9
|
Rugg EL, Common JEA, Wilgoss A, Stevens HP, Buchan J, Leigh IM, Kelsell DP. Diagnosis and confirmation of epidermolytic palmoplantar keratoderma by the identification of mutations in keratin 9 using denaturing high-performance liquid chromatography. Br J Dermatol 2002; 146:952-7. [PMID: 12072061 DOI: 10.1046/j.1365-2133.2002.04764.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Epidermolytic palmoplantar keratoderma (EPPK) is one of a number of disorders characterized by diffuse thickening of palm and sole skin. Although EPPK is not a life-threatening condition, palmoplantar keratoderma can be associated with cancer and heart disease and therefore differential diagnosis is important so that adequate surveillance can be provided for the more serious conditions. Most cases of EPPK are caused by mutations in the gene encoding the palm- and sole-specific keratin 9 (K9), and this provides an option for molecular diagnosis of this condition. OBJECTIVES To identify the molecular basis of diffuse palmoplantar keratoderma in four British families. METHODS Denaturing high-performance liquid chromatography (dHPLC) and DNA sequencing were used to screen exon 1 of the k9 gene for sequence variations. RESULTS The dHPLC profiles obtained from individuals with EPPK differed from control samples, indicating sequence variations within the fragment analysed. The profiles varied between families, suggesting that underlying mutations were different for each family; this was confirmed by DNA sequencing. In three cases previously reported mutations were found that resulted in the change of methionine156 to valine and arginine162 to either tryptophan or glutamine. A novel mutation was identified in a fourth family that changed valine170 to methionine. dHPLC was used to screen control samples for this sequence variation and confirmed that it was not a common polymorphism. CONCLUSIONS These results confirm the diagnosis of EPPK in these families and underline the usefulness of dHPLC as a method of screening samples for heterozygous mutations.
Collapse
Affiliation(s)
- E L Rugg
- Centre for Cutaneous Research, Barts and The London, Queen Mary's School of Medicine and Dentistry, University of London, 2 Newark Street, London E1 2AT, UK.
| | | | | | | | | | | | | |
Collapse
|
10
|
Amichai B, Karpati M, Goldman B, Peleg L. Keratin-9 gene mutation in a family with epidermolytic palmoplantar keratoderma. J Eur Acad Dermatol Venereol 2002; 16:134-6. [PMID: 12046815 DOI: 10.1046/j.1468-3083.2002.00426.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Epidermolytic palmoplantar keratoderma is an autosomal dominant inherited disorder of keratinization. METHODS We studied five members of a Jewish family with epidermolytic palmoplantar keratoderma. Genomic DNA was extracted from leucocytes, and exon 1 of the keratin 9 gene was amplified using polymerase chain reaction techniques. RESULTS The mutation was found in exon 1 of the keratin 9 gene in codon 160. CONCLUSIONS Like most of the other families with clinical features of epidermolytic palmoplantar keratoderma the mutation is found in exon 1 of the keratin 9 gene.
Collapse
Affiliation(s)
- B Amichai
- Department of Dermatology, Huzot Clinic of Kupat Holim, Ashkelon, Israel
| | | | | | | |
Collapse
|
11
|
Affiliation(s)
- A S Paller
- Departments of Pediatrics and Dermatology, Northwestern University Medical School, Chicago, Illinois, USA.
| |
Collapse
|