1
|
Wang YL, Chu KY, Hsieh TF, Yao CCJ, Lin CH, Lee ZH, Wang SK. Orodental malformations associated with human MSX1 sequence variants. J Am Dent Assoc 2024; 155:484-495.e21. [PMID: 38713117 DOI: 10.1016/j.adaj.2024.02.010] [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: 11/27/2023] [Revised: 02/20/2024] [Accepted: 02/21/2024] [Indexed: 05/08/2024]
Abstract
BACKGROUND MSX1 sequence variants have been known to cause human tooth agenesis (TA) with or without orofacial clefts. However, their roles during the whole processes of tooth development are not fully understood. This study aimed to characterize a 4-membered family with TA carrying a novel MSX1 pathogenic variant and investigate the disease mechanism. METHODS The authors conducted whole exome analysis to define the disease-causing sequence variant. They performed microcomputed tomography, morphometric analyses, transcriptome profiling, and molecular characterization to study the affected teeth and the gene variant. RESULTS The authors identified an MSX1 pathogenic variant, p.Glu232∗, in affected family members with TA and concomitant orodental anomalies, namely, prominent maxillary labial frenum, central incisor diastema, median maxillary anterior alveolar cleft, tooth fusion, mandibular molar dysmorphology, thin dentin layer, and slender dental roots. MSX1-defective teeth were not apparently microdontic but had thin dentin layers. The mandibular molars showed a homeotic transformation to maxillary counterparts. Genes involved in extracellular matrix organization and dentinogenesis, such as DMP1 and MMP20, were downregulated in dental pulp tissues of MSX1-defective teeth. The p.Glu232∗-truncated MSX1 properly localized to the nucleus but partially lost its transactivation ability. Analyzing reported cases indicated that truncation sequence variants within the homeobox domain of MSX1 caused a more severe TA phenotype than those outside of the homeobox domain, probably due to dominant negativity compared with haploinsufficiency. CONCLUSIONS This study provides in vivo evidence that MSX1 contributes to developmental processes of various orodental tissues in humans. PRACTICAL IMPLICATIONS Clinically, hypertrophic labial frenum, incisor diastema, and median maxillary anterior alveolar cleft might be considered diagnostic for MSX1-associated TA.
Collapse
|
2
|
Knill C, Henderson EJ, Johnson C, Wah VY, Cheng K, Forster AJ, Itasaki N. Defects of the spliceosomal gene SNRPB affect osteo- and chondro-differentiation. FEBS J 2024; 291:272-291. [PMID: 37584444 DOI: 10.1111/febs.16934] [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: 03/06/2023] [Revised: 07/25/2023] [Accepted: 08/14/2023] [Indexed: 08/17/2023]
Abstract
Although gene splicing occurs throughout the body, the phenotype of spliceosomal defects is largely limited to specific tissues. Cerebro-costo-mandibular syndrome (CCMS) is one such spliceosomal disease, which presents as congenital skeletal dysmorphism and is caused by mutations of SNRPB gene encoding Small Nuclear Ribonucleoprotein Polypeptides B/B' (SmB/B'). This study employed in vitro cell cultures to monitor osteo- and chondro-differentiation and examined the role of SmB/B' in the differentiation process. We found that low levels of SmB/B' by knockdown or mutations of SNRPB led to suppressed osteodifferentiation in Saos-2 osteoprogenitor-like cells, which was accompanied by affected splicing of Dlx5. On the other hand, low SmB/B' led to promoted chondrogenesis in HEPM mesenchymal stem cells. Consistent with other reports, osteogenesis was promoted by the Wnt/β-catenin pathway activator and suppressed by Wnt and BMP blockers, whereas chondrogenesis was promoted by Wnt inhibitors. Suppressed osteogenic markers by SNRPB knockdown were partly rescued by Wnt/β-catenin pathway activation. Reporter analysis revealed that suppression of SNRPB results in attenuated Wnt pathway and/or enhanced BMP pathway activities. SNRPB knockdown altered splicing of TCF7L2 which impacts Wnt/β-catenin pathway activities. This work helps unravel the mechanism underlying CCMS whereby reduced expression of spliceosomal proteins causes skeletal phenotypes.
Collapse
Affiliation(s)
- Chris Knill
- Faculty of Life Sciences, University of Bristol, UK
| | | | - Craig Johnson
- Faculty of Health Sciences, University of Bristol, UK
| | - Vun Yee Wah
- Faculty of Life Sciences, University of Bristol, UK
| | - Kevin Cheng
- Faculty of Life Sciences, University of Bristol, UK
| | | | - Nobue Itasaki
- Faculty of Health Sciences, University of Bristol, UK
| |
Collapse
|
3
|
Zhao Y, Ren J, Meng L, Hou Y, Liu C, Zhang G, Shen W. Characterization of novel MSX1 variants causally associated with non-syndromic oligodontia in Chinese families. Mol Genet Genomic Med 2024; 12:e2334. [PMID: 38069551 PMCID: PMC10767605 DOI: 10.1002/mgg3.2334] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 09/03/2023] [Accepted: 11/28/2023] [Indexed: 01/07/2024] Open
Abstract
BACKGROUND MSX1 (OMIM #142983) is crucial to normal dental development, and variants in MSX1 are associated with dental anomalies. The objective of this study was to characterize the pathogenicity of novel MSX1 variants in Chinese families with non-syndromic oligodontia (NSO). METHODS Genomic DNA was extracted from individuals representing 35 families with non-syndromic oligodontia and was analyzed by Sanger sequencing and whole-exome sequencing. Pathogenic variants were screened via analyses involving PolyPhen-2, Sorting-Intolerant from Tolerant, and MutationTaster, and conservative analysis of variants. Patterns of MSX1-related NSO were analyzed. MSX1 structural changes suggested functional consequences in vitro. RESULTS Three previously unreported MSX1 heterozygous variants were identified: one insertion variant (c.576_577insTAG; p.Gln193*) and two missense variants (c. 871T>C; p.Tyr291His and c. 644A>C; p.Gln215Pro). Immunofluorescence analysis revealed abnormal subcellular localization of the p.Gln193* MSX1 variant. In addition, we found that these MSX1 variants likely lead to the loss of second premolars. CONCLUSION Three novel MSX1 variants were identified in Chinese Han families with NSO, expanding the MSX1 variant spectrum and presenting a genetic origin for the pathogenesis detected in patients and their families.
Collapse
Affiliation(s)
- Ya Zhao
- Department of Prosthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| | - Jiabao Ren
- Department of Prosthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| | - Lingqiang Meng
- Department of Prosthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| | - Yan Hou
- Department of Orthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| | - Chunyan Liu
- Department of Orthodontics, Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| | - Guozhong Zhang
- College of Forensic MedicineHebei Medical UniversityShijiazhuangPR China
| | - Wenjing Shen
- Hebei Key Laboratory of Stomatology, Hebei Clinical Research Center for Oral Diseases, School and Hospital of StomatologyHebei Medical UniversityShijiazhuangPR China
| |
Collapse
|
4
|
Lone IM, Zohud O, Midlej K, Awadi O, Masarwa S, Krohn S, Kirschneck C, Proff P, Watted N, Iraqi FA. Narrating the Genetic Landscape of Human Class I Occlusion: A Perspective-Infused Review. J Pers Med 2023; 13:1465. [PMID: 37888076 PMCID: PMC10608728 DOI: 10.3390/jpm13101465] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 09/27/2023] [Accepted: 10/03/2023] [Indexed: 10/28/2023] Open
Abstract
This review examines a prevalent condition with multifaceted etiology encompassing genetic, environmental, and oral behavioral factors. It stands as a significant ailment impacting oral functionality, aesthetics, and quality of life. Longitudinal studies indicate that malocclusion in primary dentition may progress to permanent malocclusion. Recognizing and managing malocclusion in primary dentition is gaining prominence. The World Health Organization ranks malocclusions as the third most widespread oral health issue globally. Angle's classification system is widely used to categorize malocclusions, with Class I occlusion considered the norm. However, its prevalence varies across populations due to genetic and examination disparities. Genetic factors, including variants in genes like MSX1, PAX9, and AXIN2, have been associated with an increased risk of Class I occlusion. This review aims to provide a comprehensive overview of clinical strategies for managing Class I occlusion and consolidate genetic insights from both human and murine populations. Additionally, genomic relationships among craniofacial genes will be assessed in individuals with Class I occlusion, along with a murine model, shedding light on phenotype-genotype associations of clinical relevance. The prevalence of Class I occlusion, its impact, and treatment approaches will be discussed, emphasizing the importance of early intervention. Additionally, the role of RNA alterations in skeletal Class I occlusion will be explored, focusing on variations in expression or structure that influence craniofacial development. Mouse models will be highlighted as crucial tools for investigating mandible size and prognathism and conducting QTL analysis to gain deeper genetic insights. This review amalgamates cellular, molecular, and clinical trait data to unravel correlations between malocclusion and Class I phenotypes.
Collapse
Affiliation(s)
- Iqbal M. Lone
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel; (I.M.L.); (O.Z.); (K.M.)
| | - Osayd Zohud
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel; (I.M.L.); (O.Z.); (K.M.)
| | - Kareem Midlej
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel; (I.M.L.); (O.Z.); (K.M.)
| | - Obaida Awadi
- Center for Dentistry Research and Aesthetics, Jatt 45911, Israel; (O.A.); (S.M.); (N.W.)
| | - Samir Masarwa
- Center for Dentistry Research and Aesthetics, Jatt 45911, Israel; (O.A.); (S.M.); (N.W.)
| | - Sebastian Krohn
- Department of Orthodontics, University Hospital of Regensburg, University of Regensburg, 93053 Regensburg, Germany; (S.K.); (C.K.); (P.P.)
| | - Christian Kirschneck
- Department of Orthodontics, University Hospital of Regensburg, University of Regensburg, 93053 Regensburg, Germany; (S.K.); (C.K.); (P.P.)
| | - Peter Proff
- Department of Orthodontics, University Hospital of Regensburg, University of Regensburg, 93053 Regensburg, Germany; (S.K.); (C.K.); (P.P.)
| | - Nezar Watted
- Center for Dentistry Research and Aesthetics, Jatt 45911, Israel; (O.A.); (S.M.); (N.W.)
- Department of Orthodontics, Faculty of Dentistry, Arab America University, Jenin 919000, Palestine
- Gathering for Prosperity Initiative, Jatt 45911, Israel
| | - Fuad A. Iraqi
- Department of Clinical Microbiology and Immunology, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv 69978, Israel; (I.M.L.); (O.Z.); (K.M.)
- Department of Orthodontics, University Hospital of Regensburg, University of Regensburg, 93053 Regensburg, Germany; (S.K.); (C.K.); (P.P.)
- Gathering for Prosperity Initiative, Jatt 45911, Israel
| |
Collapse
|
5
|
Pitfalls of whole exome sequencing in undefined clinical conditions with a suspected genetic etiology. Genes Genomics 2022; 45:637-655. [PMID: 36454368 DOI: 10.1007/s13258-022-01341-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 10/26/2022] [Indexed: 12/03/2022]
Abstract
BACKGROUND Whole-Exome Sequencing (WES) is a valuable tool for the molecular diagnosis of patients with a suspected genetic condition. In complex and heterogeneous diseases, the interpretation of WES variants is more challenging given the absence of diagnostic handles and other reported cases with overlapping clinical presentations. OBJECTIVE To describe candidate variants emerging from trio-WES and possibly associated with the clinical phenotype in clinically heterogeneous conditions. METHODS We performed WES in ten patients from eight families, selected because of the lack of a clear clinical diagnosis or suspicion, the presence of multiple clinical signs, and the negative results of traditional genetic tests. RESULTS Although we identified ten candidate variants, reaching the diagnosis of these cases is challenging, given the complexity and the rarity of these syndromes and because affected genes are already associated with known genetic diseases only partially recapitulating patients' phenotypes. However, the identification of these variants could shed light into the definition of new genotype-phenotype correlations. Here, we describe the clinical and molecular data of these cases with the aim of favoring the match with other similar cases and, hopefully, confirm our diagnostic hypotheses. CONCLUSION This study emphasizes the major limitations associated with WES data interpretation, but also highlights its clinical utility in unraveling novel genotype-phenotype correlations in complex and heterogeneous undefined clinical conditions with a suspected genetic etiology.
Collapse
|
6
|
Chavez-Granados PA, Manisekaran R, Acosta-Torres LS, Garcia-Contreras R. CRISPR/Cas gene-editing technology and its advances in dentistry. Biochimie 2021; 194:96-107. [PMID: 34974144 DOI: 10.1016/j.biochi.2021.12.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/14/2021] [Accepted: 12/27/2021] [Indexed: 12/25/2022]
Abstract
A recent discovery of revolutionary Clustered regularly interspaced palindromic repeats (CRISPR) is a gene-editing tool that provides a type of adaptive immunity in prokaryotic organisms, which is currently used as a revolutionizing tool in biomedical research. It has a mechanism of correcting genome errors, turning on/off genes in cells and organisms. Most importantly playing a crucial function in bacterial defence by identifying and destroying Deoxyribonucleic acid (DNA) segments during bacteriophage invasions since the CRISPR-associated protein 9 (Cas9) enzyme recognizes and cleaves invasive DNA sequences complementary to CRISPR. Therefore, researchers employ this biological device to manipulate the genes to develop new therapies to combat systemic diseases. Currently, the most significant advance at the laboratory level is the generation of cell and animal models, functional genomic screens, live images of the cell genome, and defective DNA repairs to find the cure for genetic disorders. Even though this technology has enormous biomedical applications in various sectors, this review will summarize CRISPR/Cas emphasizing both the therapeutic and diagnostic mechanisms developed in the field of dentistry and the promising attempts to transfer this technology to clinical application. Finally, future developments are also described, which proposes to use CRISPR/Cas systems for prospective clinical dentistry applications.
Collapse
Affiliation(s)
- Patricia Alejandra Chavez-Granados
- Interdisciplinary Research Laboratory (LII), Nanostructures and Biomaterials Area, National School of Higher Studies (ENES) León Unit, Predio el Saucillo y el Potrero, Comunidad de los Tepetates, 37684, León, Mexico
| | - Ravichandran Manisekaran
- Interdisciplinary Research Laboratory (LII), Nanostructures and Biomaterials Area, National School of Higher Studies (ENES) León Unit, Predio el Saucillo y el Potrero, Comunidad de los Tepetates, 37684, León, Mexico
| | - Laura Susana Acosta-Torres
- Interdisciplinary Research Laboratory (LII), Nanostructures and Biomaterials Area, National School of Higher Studies (ENES) León Unit, Predio el Saucillo y el Potrero, Comunidad de los Tepetates, 37684, León, Mexico
| | - Rene Garcia-Contreras
- Interdisciplinary Research Laboratory (LII), Nanostructures and Biomaterials Area, National School of Higher Studies (ENES) León Unit, Predio el Saucillo y el Potrero, Comunidad de los Tepetates, 37684, León, Mexico.
| |
Collapse
|
7
|
Shin YK, Cheon S, Kim SD, Moon JS, Kim JY, Kim SH, Park C, Kim MS. Identification of novel candidate genes implicated in odontogenic potential in the developing mouse tooth germ using transcriptome analysis. Genes Genomics 2021; 43:1087-1094. [PMID: 34302633 DOI: 10.1007/s13258-021-01130-y] [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: 04/20/2021] [Accepted: 06/21/2021] [Indexed: 11/26/2022]
Abstract
BACKGROUND In tooth bioengineering for replacement therapy of missing teeth, the utilized cells must possess an inductive signal-forming ability to initiate odontogenesis. This ability is called odontogenic potential. In mice, the odontogenic potential signal is known to be translocated from the epithelium to the mesenchyme at the early bud stage in the developing molar tooth germ. However, the identity of the molecular constituents of this process remains unclear. OBJECTIVE The purpose of this study is to determine the molecular identity of odontogenic potential and to provide a new perspective in the field of tooth development research. METHODS In this study, whole transcriptome profiles of the mouse molar tooth germ epithelium and mesenchyme were investigated using the RNA sequencing (RNA-seq) technique. The analyzed transcriptomes corresponded to two developmental stages, embryonic day 11.5 (E11.5) and 14.5 (E14.5), which represent the odontogenic potential shifts. RESULTS We identified differentially expressed genes (DEGs), which were specifically overexpressed in both the E11.5 epithelium and E14.5 mesenchyme, but not expressed in their respective counterparts. Of the 55 DEGs identified, the top three most expressed transcription factor genes (transcription factor AP-2 beta isoform 3 [TFAP2B], developing brain homeobox protein 2 [DBX2], and insulin gene enhancer protein ISL-1 [ISL1]) and three tooth development-related genes (transcription factor HES-5 [HES5], platelet-derived growth factor D precursor [PDGFD], semaphrin-3 A precursor [SEMA3A]) were selected and validated by quantitative RT-PCR. Using immunofluorescence staining, the TFAP2B protein expression was found to be localized only at the E11.5 epithelium and E14.5 mesenchyme. CONCLUSIONS Thus, our empirical findings in the present study may provide a new perspective into the characterization of the molecules responsible for the odontogenic potential and may have an implication in the cell-based whole tooth regeneration strategy.
Collapse
Affiliation(s)
- Yeo-Kyeong Shin
- Dental Science Research Institute, School of Dentistry, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea
| | - Seongmin Cheon
- School of Biological Sciences and Technology, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea
| | - Sung-Duk Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea
| | - Jung-Sun Moon
- Dental Science Research Institute, School of Dentistry, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea
| | - Jae-Young Kim
- Department of Biochemistry, School of Dentistry, IHBR, Kyungpook National University, Daegu, South Korea
| | - Sun-Hun Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea
| | - Chungoo Park
- School of Biological Sciences and Technology, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea.
| | - Min-Seok Kim
- Dental Science Research Institute, School of Dentistry, Chonnam National University, 300 Yongbong-Dong, Buk-Ku, Gwangju, 61186, South Korea.
| |
Collapse
|
8
|
Hassan MG, Zaher AR, Athanasiou AE. How orthodontic research can be enriched and advanced by the novel and promising evolutions in biomedicine. J Orthod 2021; 48:288-294. [PMID: 33860691 DOI: 10.1177/14653125211006116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Recent advances in developmental, molecular and cellular biology as well as biomedical technologies show a promising future for crossing the gap between biomedical basic sciences and clinical orthodontics. Orthodontic research shall utilise the advances and technologies in biomedical fields including genomics, molecular biology, bioinformatics and developmental biology. This review provides an update on the novel and promising evolutions in biomedicine and highlights their current and likely future implementation to orthodontic practice. Biotechnological opportunities in orthodontics and dentofacial orthopaedics are presented with regards to CRISPR technology, multi-omics sequencing, gene therapy, stem cells and regenerative medicine. Future orthodontic advances in terms of translational research are also discussed. Given the breadth of applications and the great number of questions that the presently available novel biomedical tools and techniques raise, their use may provide orthodontic research in the future with a great potential in understanding the aetiology of dentofacial deformities and malocclusions as well as in improving the practice of this clinical specialty.
Collapse
Affiliation(s)
- Mohamed G Hassan
- Department of Orthodontics, Faculty of Oral and Dental Medicine, South Valley University, Qena, Egypt
| | - Abbas R Zaher
- Department of Orthodontics, Faculty of Dentistry, Alexandria University, Alexandria, Egypt
| | - Athanasios E Athanasiou
- Department of Dentistry, School of Medicine, European University Cyprus, Nicosia, Cyprus.,Hamdan Bin Mohammed College of Dental Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, United Arab Emirates
| |
Collapse
|
9
|
Novel MSX1 variants identified in families with nonsyndromic oligodontia. Int J Oral Sci 2021; 13:2. [PMID: 33419968 PMCID: PMC7794556 DOI: 10.1038/s41368-020-00106-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 11/24/2020] [Accepted: 11/26/2020] [Indexed: 11/08/2022] Open
Abstract
The goal of this study was to identify MSX1 gene variants in multiple Chinese families with nonsyndromic oligodontia and analyse the functional influence of these variants. Whole-exome sequencing (WES) and Sanger sequencing were performed to identify the causal gene variants in five families with nonsyndromic oligodontia, and a series of bioinformatics databases were used for variant confirmation and functional prediction. Phenotypic characterization of the members of these families was described, and an in vitro analysis was performed for functional evaluation. Five novel MSX1 heterozygous variants were identified: three missense variants [c.662A>C (p.Q221P), c.670C>T (p.R224C), and c.809C>T (p.S270L)], one nonsense variant [c.364G>T (p.G122*)], and one frameshift variant [c.277delG (p.A93Rfs*67)]. Preliminary in vitro studies demonstrated that the subcellular localization of MSX1 was abnormal with the p.Q221P, p.R224C, p.G122*, and p.A93Rfs*67 variants compared to the wild type. Three variants (p.Q221P, p.G122*, and p.A93Rfs*67) were classified as pathogenic or likely pathogenic, while p.S270L and p.R224C were of uncertain significance in the current data. Moreover, we summarized and analysed the MSX1-related tooth agenesis positions and found that the type and variant locus were not related to the severity of tooth loss. Our results expand the variant spectrum of nonsyndromic oligodontia and provide valuable information for genetic counselling.
Collapse
|
10
|
Ichihara A, Yasue A, Mitsui SN, Arai D, Minegishi Y, Oyadomari S, Imoto I, Tanaka E. The C-terminal region including the MH6 domain of Msx1 regulates skeletal development. Biochem Biophys Res Commun 2020; 526:62-69. [PMID: 32192766 DOI: 10.1016/j.bbrc.2020.03.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 03/10/2020] [Indexed: 10/24/2022]
Abstract
MSX1 is a causative gene for oligodontia in humans. Although conventional Msx1-deficient mice die neonatally, a mutant mouse lacking the C-terminus MH6 domain of MSX1 (Msx1ΔMH6/ΔMH6) showed two different phenotypes; newborn homozygotes with cleft palates died neonatally, whereas those with thin palates remained alive and had craniofacial dysplasia and growth retardation compared with wild-type mice, with most mice dying by the age of 4-5 weeks. In a previously reported case of human oligodontia caused by a heterozygous defect of the Msx1 MH6 domain, a small foramen was observed on the occipital bone. The aim of this study was to test the hypothesis that the Msx1 MH6 domain is involved in bone formation in vivo. In Msx1ΔMH6/ΔMH6 mice, cranial suture fusion was delayed at embryonic day 18.5, and the anteroposterior cranial diameter was smaller and long bone length was decreased at 3 weeks of age. The femoral epiphysis showed no change in the trabecular number, but decreased bone mass, bone density, and trabecular width in Msx1ΔMH6/ΔMH6 mice. In addition, cancellous bone mass was reduced and the cartilage layer in the growth plate was thinner in Msx1ΔMH6/ΔMH6 mice. The mRNA expression levels of major osteoblast and chondrocyte differentiation marker genes were decreased in Msx1ΔMH6/ΔMH6 mice compared with wild-type mice. These findings suggest that the C-terminal region including the MH6 domain of MSX1 plays important roles not only in tooth development and palatal fusion, but also in postnatal bone formation.
Collapse
Affiliation(s)
- Aki Ichihara
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8504, Japan
| | - Akihiro Yasue
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8504, Japan.
| | - Silvia Naomi Mitsui
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8504, Japan
| | - Daishi Arai
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8504, Japan
| | - Yoshiyuki Minegishi
- Division of Molecular Medicine, Institute of Advanced Enzyme Research, Tokushima University, Tokushima, 770-8503, Japan
| | - Seiichi Oyadomari
- Division of Molecular Biology, Institute for Genome Research, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, 770-8503, Japan
| | - Issei Imoto
- Department of Human Genetics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8503, Japan; Division of Molecular Genetics, Aichi Cancer Center Research Institute, Aichi, 464-8681, Japan; Division of Cancer Genetics, Nagoya University Graduate School of Medicine, Aichi, 466-8550, Japan
| | - Eiji Tanaka
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, 770-8504, Japan
| |
Collapse
|
11
|
|
12
|
Yu N, Yang J, Mishina Y, Giannobile WV. Genome Editing: A New Horizon for Oral and Craniofacial Research. J Dent Res 2018; 98:36-45. [PMID: 30354846 DOI: 10.1177/0022034518805978] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Precise and efficient genetic manipulations have enabled researchers to understand gene functions in disease and development, providing a platform to search for molecular cures. Over the past decade, the unprecedented advancement of genome editing techniques has revolutionized the biological research fields. Early genome editing strategies involved many naturally occurring nucleases, including meganucleases, zinc finger nucleases, and transcription activator-like effector-based nucleases. More recently, the clustered regularly interspaced short palindromic repeats (CRISPR) / CRISPR-associated nucleases (CRISPR/Cas) system has greatly enriched genetic manipulation methods in conducting research. Those nucleases generate double-strand breaks in the target gene sequences and then utilize DNA repair mechanisms to permit precise yet versatile genetic manipulations. The oral and craniofacial field harbors a plethora of diseases and developmental defects that require genetic models that can exploit these genome editing techniques. This review provides an overview of the genome editing techniques, particularly the CRISPR/Cas9 technique, for the oral and craniofacial research community. We also discuss the details about the emerging applications of genome editing in oral and craniofacial biology.
Collapse
Affiliation(s)
- N Yu
- 1 Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - J Yang
- 2 Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.,3 The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Y Mishina
- 2 Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI, USA
| | - W V Giannobile
- 1 Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.,4 Department of Biomedical Engineering, College of Engineering, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|