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Alzahem TA, AlTheeb A, Ba-Abbad R. PRPS1-associated retinopathy: a diagnostic odyssey. Ophthalmic Genet 2024:1-5. [PMID: 38619019 DOI: 10.1080/13816810.2024.2321871] [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: 11/06/2023] [Accepted: 02/18/2024] [Indexed: 04/16/2024]
Abstract
PURPOSE This study describes how the diagnosis of Usher syndrome was revised to PRPS1-associated retinopathy and Charcot-Marie-Tooth disease type 5. CASE REPORT A 38-year-old female with bilaterally subnormal vision and non-congenital hearing loss was initially diagnosed with Usher syndrome, based on finding variants in three genes (MYO7A, USH2A, and PCDH15), was re-evaluated at the inherited retinal disorders clinic. She had asymmetric retinopathy and right macular pseudocoloboma. She was also found to have myopathic facies, poor grip strength and atrophy of the calf muscles. Whole exome sequencing including variants in PRPS1 showed a variant (NM_002764.4:c.287 G > A; p.Arg96Gln), which was not detected by targeted Sanger sequencing of the DNA from her mother and sister. CONCLUSION The constellation of asymmetric retinopathy and non-congenital hearing impairment should prompt the clinician to search for other diagnoses that may not be covered by an Usher syndrome next generation sequencing panel. Interpretation of genetic testing results should be correlated with a detailed clinical phenotype.
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Affiliation(s)
- Tariq A Alzahem
- Ocular Genetics Service, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
- Ophthalmology Department, King Saud University Medical City, Riyadh, Saudi Arabia
| | - Abdulwahab AlTheeb
- Ocular Genetics Service, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Rola Ba-Abbad
- Ocular Genetics Service, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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2
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Chen L, Zhou Q, Zhang P, Tan W, Li Y, Xu Z, Ma J, Kupfer GM, Pei Y, Song Q, Pei H. Direct stimulation of de novo nucleotide synthesis by O-GlcNAcylation. Nat Chem Biol 2024; 20:19-29. [PMID: 37308732 PMCID: PMC10746546 DOI: 10.1038/s41589-023-01354-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 05/03/2023] [Indexed: 06/14/2023]
Abstract
O-linked β-N-acetyl glucosamine (O-GlcNAc) is at the crossroads of cellular metabolism, including glucose and glutamine; its dysregulation leads to molecular and pathological alterations that cause diseases. Here we report that O-GlcNAc directly regulates de novo nucleotide synthesis and nicotinamide adenine dinucleotide (NAD) production upon abnormal metabolic states. Phosphoribosyl pyrophosphate synthetase 1 (PRPS1), the key enzyme of the de novo nucleotide synthesis pathway, is O-GlcNAcylated by O-GlcNAc transferase (OGT), which triggers PRPS1 hexamer formation and relieves nucleotide product-mediated feedback inhibition, thereby boosting PRPS1 activity. PRPS1 O-GlcNAcylation blocked AMPK binding and inhibited AMPK-mediated PRPS1 phosphorylation. OGT still regulates PRPS1 activity in AMPK-deficient cells. Elevated PRPS1 O-GlcNAcylation promotes tumorigenesis and confers resistance to chemoradiotherapy in lung cancer. Furthermore, Arts-syndrome-associated PRPS1 R196W mutant exhibits decreased PRPS1 O-GlcNAcylation and activity. Together, our findings establish a direct connection among O-GlcNAc signals, de novo nucleotide synthesis and human diseases, including cancer and Arts syndrome.
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Affiliation(s)
- Lulu Chen
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Qi Zhou
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Pingfeng Zhang
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China
| | - Wei Tan
- Department of Lymphoma and Myeloma, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yingge Li
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Ziwen Xu
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Junfeng Ma
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Gary M Kupfer
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA
| | - Yanxin Pei
- Center for Cancer and Immunology, Brain Tumor Institute, Children's National Health System, Washington, DC, USA
| | - Qibin Song
- Cancer Center, Renmin Hospital of Wuhan University, Wuhan, China.
| | - Huadong Pei
- Department of Oncology, Georgetown Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, Washington, DC, USA.
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3
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Lee A, Knox R, Reynolds M, McRoy E, Nguyen H. S-adenosylmethionine and nicotinamide riboside therapy in Arts syndrome: A case report and literature review. JIMD Rep 2023; 64:417-423. [PMID: 37927483 PMCID: PMC10623096 DOI: 10.1002/jmd2.12395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/18/2023] [Accepted: 08/22/2023] [Indexed: 11/07/2023] Open
Abstract
Phospho-ribosyl-pyrophosphate synthetase 1 (PRPS1) deficiency is secondary to loss of function variants in PRPS1. This enzyme generates phospho-ribosyl-pyrophosphate (PRPP), which is utilized in the synthesis of purines, nicotinamide adenine dinucleotide (NAD), and NAD phosphate (NADP), among other metabolic pathways. Arts syndrome, or severe PRPS1 deficiency, is an X-linked condition characterized by congenital sensorineural hearing loss, optic atrophy, developmental delays, ataxia, hypotonia, and recurrent infections that can cause progressive clinical decline, often resulting in death before 5 years of age. Supplementation of the purine and NAD pathways outside of PRPP-dependent reactions is a logical approach and has been reported in a handful of patients, two with S-adenosylmethionine (SAMe) and one with SAMe and nicotinamide riboside (NR). We present the clinical course of a fourth Arts syndrome patient who was started on therapy and review previously reported patients. All patients had stability or improvement of symptoms, suggesting that SAMe and NR can be a treatment option in Arts syndrome, though further studies are warranted.
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Affiliation(s)
- Angela Lee
- Department of Pediatrics, Division of Genetics and Genomic MedicineWashington UniversitySaint LouisMissouriUSA
| | - Renatta Knox
- Department of Pediatrics and NeurologyWashington UniversitySaint LouisMissouriUSA
| | - Margaret Reynolds
- Departments of Pediatrics, Division of OphthalmologyWashington UniversitySaint LouisMissouriUSA
| | - Erin McRoy
- Department of Pediatrics, Division of Genetics and Genomic MedicineWashington UniversitySaint LouisMissouriUSA
| | - Hoanh Nguyen
- Department of Pediatrics, Division of Genetics and Genomic MedicineWashington UniversitySaint LouisMissouriUSA
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4
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Štajer K, Kovač N, Šikonja J, Mlinarič M, Bertok S, Brecelj J, Debeljak M, Kovač J, Markelj G, Neubauer D, Rus R, Žerjav Tanšek M, Drole Torkar A, Zver A, Battelino T, Jiménez Torres R, Grošelj U. Clinical and genetic characteristics of a patient with phosphoribosyl pyrophosphate synthetase 1 deficiency and a systematic literature review. Mol Genet Metab Rep 2023; 36:100986. [PMID: 37670898 PMCID: PMC10475845 DOI: 10.1016/j.ymgmr.2023.100986] [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: 04/07/2023] [Revised: 06/01/2023] [Accepted: 06/02/2023] [Indexed: 09/07/2023] Open
Abstract
Phosphoribosylpyrophosphate synthetase 1 (PRS-I) is an enzyme involved in nucleotide metabolism. Pathogenic variants in the PRPS1 are rare and PRS-I deficiency can manifest as three clinical syndromes: X-linked non-syndromic sensorineural deafness (DFN2), X-linked Charcot-Marie-Tooth neuropathy type 5 (CMTX5) and Arts syndrome. We present a Slovenian patient with PRS-I enzyme deficiency due to a novel pathogenic variant - c.424G > A (p.Val142Ile) in the PRPS1 gene, who presented with gross motor impairment, severe sensorineural deafness, balance issues, ataxia, and frequent respiratory infections. In addition, we report the findings of a systemic literature review of all described male cases of Arts syndrome and CMTX5 as well as intermediate phenotypes. As already proposed by other authors, our results confirm PRS-I deficiency should be viewed as a phenotypic continuum rather than three separate syndromes because there are multiple reports of patients with an intermediary clinical presentation.
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Affiliation(s)
- Katarina Štajer
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Neja Kovač
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Jaka Šikonja
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Matej Mlinarič
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Sara Bertok
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Jernej Brecelj
- Department of Gastroenterology, Hepatology and Nutrition, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Maruša Debeljak
- Laboratory of Genetics, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Jernej Kovač
- Laboratory of Genetics, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Gašper Markelj
- Department of Allergology, Rheumatology and Clinical Immunology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - David Neubauer
- Department of Child, Adolescent and Developmental Neurologyx, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Rina Rus
- Department of Nephrology, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Mojca Žerjav Tanšek
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Ana Drole Torkar
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Aleksandra Zver
- Unit for Pulmonary Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Tadej Battelino
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Rosa Jiménez Torres
- La Paz University Hospital Health Research Institute (FIBHULP), IdiPaz, Madrid, Spain
- Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Spain
| | - Urh Grošelj
- Department of Endocrinology, Diabetes, and Metabolic Diseases, University Children's Hospital, University Medical Centre Ljubljana, Ljubljana, Slovenia
- Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
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5
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Cellular and Molecular Mechanisms of Pathogenesis Underlying Inherited Retinal Dystrophies. Biomolecules 2023; 13:biom13020271. [PMID: 36830640 PMCID: PMC9953031 DOI: 10.3390/biom13020271] [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: 12/21/2022] [Revised: 01/23/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Inherited retinal dystrophies (IRDs) are congenital retinal degenerative diseases that have various inheritance patterns, including dominant, recessive, X-linked, and mitochondrial. These diseases are most often the result of defects in rod and/or cone photoreceptor and retinal pigment epithelium function, development, or both. The genes associated with these diseases, when mutated, produce altered protein products that have downstream effects in pathways critical to vision, including phototransduction, the visual cycle, photoreceptor development, cellular respiration, and retinal homeostasis. The aim of this manuscript is to provide a comprehensive review of the underlying molecular mechanisms of pathogenesis of IRDs by delving into many of the genes associated with IRD development, their protein products, and the pathways interrupted by genetic mutation.
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6
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Xiong G, Feng Y, Yi X, Zhang X, Li X, Yang L, Yi Z, Sai B, Yang Z, Zhang Q, Kuang Y, Zhu Y. NRF2-directed PRPS1 upregulation to promote the progression and metastasis of melanoma. Front Immunol 2022; 13:989263. [PMID: 36203561 PMCID: PMC9530353 DOI: 10.3389/fimmu.2022.989263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Phosphoribosyl pyrophosphate synthetase 1 (PRPS1) is the first enzyme in the de novo purine nucleotide synthesis pathway and is essential for cell development. However, the effect of PRPS1 on melanoma proliferation and metastasis remains unclear. This study aimed to investigate the regulatory mechanism of PRPS1 in the malignant progression of melanoma. Here, we found PRPS1 was upregulated in melanoma and melanoma cells. In addition, our data indicated that PRPS1 could promote the proliferation and migration and invasion of melanoma both in vitro and in vivo. PRPS1 also could inhibit melanoma cell apoptosis. Furthermore, we found NRF2 is an upstream transcription factor of PRPS1 that drive malignant progression of melanoma.
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Affiliation(s)
- Guohang Xiong
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Yu Feng
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Xiaojia Yi
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
- Department of Pathology, The Second Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Xuedan Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Xiaoyu Li
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Lijuan Yang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Zihan Yi
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
- Department of Medical Oncology, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province), Kunming, China
| | - Buqing Sai
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Zhe Yang
- Department of Pathology, The First Affiliated Hospital of Kunming Medical University, Kunming, China
| | - Qiao Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
| | - Yingmin Kuang
- Department of Organ Transplantation, The First Affiliated Hospital of Kunming Medical University, Kunming, China
- *Correspondence: Yuechun Zhu, ; Yingmin Kuang,
| | - Yuechun Zhu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Kunming Medical University, Kunming, China
- *Correspondence: Yuechun Zhu, ; Yingmin Kuang,
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7
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Dewulf JP, Marie S, Nassogne MC. Disorders of purine biosynthesis metabolism. Mol Genet Metab 2022; 136:190-198. [PMID: 34998670 DOI: 10.1016/j.ymgme.2021.12.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/15/2021] [Accepted: 12/25/2021] [Indexed: 11/18/2022]
Abstract
Purines are essential molecules that are components of vital biomolecules, such as nucleic acids, coenzymes, signaling molecules, as well as energy transfer molecules. The de novo biosynthesis pathway starts from phosphoribosylpyrophosphate (PRPP) and eventually leads to the synthesis of inosine monophosphate (IMP) by means of 10 sequential steps catalyzed by six different enzymes, three of which are bi-or tri-functional in nature. IMP is then converted into guanosine monophosphate (GMP) or adenosine monophosphate (AMP), which are further phosphorylated into nucleoside di- or tri-phosphates, such as GDP, GTP, ADP and ATP. This review provides an overview of inborn errors of metabolism pertaining to purine synthesis in humans, including either phosphoribosylpyrophosphate synthetase (PRS) overactivity or deficiency, as well as adenylosuccinate lyase (ADSL), 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/IMP cyclohydrolase (ATIC), phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), and adenylosuccinate synthetase (ADSS) deficiencies. ITPase deficiency is being described as well. The clinical spectrum of these disorders is broad, including neurological impairment, such as psychomotor retardation, epilepsy, hypotonia, or microcephaly; sensory involvement, such as deafness and visual disturbances; multiple malformations, as well as muscle presentations or consequences of hyperuricemia, such as gouty arthritis or kidney stones. Clinical signs are often nonspecific and, thus, overlooked. It is to be hoped that this is likely to be gradually overcome by using sensitive biochemical investigations and next-generation sequencing technologies.
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Affiliation(s)
- Joseph P Dewulf
- Laboratoire des Maladies Métaboliques Héréditaires/Biochimie Génétique et Centre de Dépistage Néonatal, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium; Institut des Maladies Rares, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium; Department of Biochemistry, de Duve Institute, UCLouvain, Brussels, Belgium.
| | - Sandrine Marie
- Laboratoire des Maladies Métaboliques Héréditaires/Biochimie Génétique et Centre de Dépistage Néonatal, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium; Institut des Maladies Rares, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium.
| | - Marie-Cécile Nassogne
- Institut des Maladies Rares, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium; Service de Neurologie Pédiatrique, Cliniques Universitaires Saint-Luc, UCLouvain, B-1200 Brussels, Belgium.
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8
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Ugbogu EA, Schweizer LM, Schweizer M. Contribution of Model Organisms to Investigating the Far-Reaching Consequences of PRPP Metabolism on Human Health and Well-Being. Cells 2022; 11:1909. [PMID: 35741038 PMCID: PMC9221600 DOI: 10.3390/cells11121909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/03/2022] [Accepted: 05/05/2022] [Indexed: 11/17/2022] Open
Abstract
Phosphoribosyl pyrophosphate synthetase (PRS EC 2.7.6.1) is a rate-limiting enzyme that irreversibly catalyzes the formation of phosphoribosyl pyrophosphate (PRPP) from ribose-5-phosphate and adenosine triphosphate (ATP). This key metabolite is required for the synthesis of purine and pyrimidine nucleotides, the two aromatic amino acids histidine and tryptophan, the cofactors nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+), all of which are essential for various life processes. Despite its ubiquity and essential nature across the plant and animal kingdoms, PRPP synthetase displays species-specific characteristics regarding the number of gene copies and architecture permitting interaction with other areas of cellular metabolism. The impact of mutated PRS genes in the model eukaryote Saccharomyces cerevisiae on cell signalling and metabolism may be relevant to the human neuropathies associated with PRPS mutations. Human PRPS1 and PRPS2 gene products are implicated in drug resistance associated with recurrent acute lymphoblastic leukaemia and progression of colorectal cancer and hepatocellular carcinoma. The investigation of PRPP metabolism in accepted model organisms, e.g., yeast and zebrafish, has the potential to reveal novel drug targets for treating at least some of the diseases, often characterized by overlapping symptoms, such as Arts syndrome and respiratory infections, and uncover the significance and relevance of human PRPS in disease diagnosis, management, and treatment.
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Affiliation(s)
- Eziuche A. Ugbogu
- School of Life Sciences, Heriot Watt University, Edinburgh EH14 4AS, UK; (E.A.U.); (L.M.S.)
| | - Lilian M. Schweizer
- School of Life Sciences, Heriot Watt University, Edinburgh EH14 4AS, UK; (E.A.U.); (L.M.S.)
| | - Michael Schweizer
- Institute of Biological Chemistry, Biophysics & Engineering (IB3), School of Engineering &Physical Sciences, Heriot Watt University, Edinburgh EH14 4AS, UK
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9
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Puusepp S, Reinson K, Pajusalu S, van Kuilenburg ABP, Dobritzsch D, Roelofsen J, Stenzel W, Õunap K. Atypical presentation of Arts syndrome due to a novel hemizygous loss-of-function variant in the PRPS1 gene. Mol Genet Metab Rep 2020; 25:100677. [PMID: 33294372 PMCID: PMC7689168 DOI: 10.1016/j.ymgmr.2020.100677] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 11/06/2020] [Accepted: 11/07/2020] [Indexed: 11/30/2022] Open
Abstract
The PRPS1 gene, located on Xq22.3, encodes phosphoribosyl-pyrophosphate synthetase (PRPS), a key enzyme in de novo purine synthesis. Three clinical phenotypes are associated with loss-of-function PRPS1 variants and decreased PRPS activity: Arts syndrome (OMIM: 301835), Charcot–Marie–Tooth disease type 5 (CMTX5, OMIM: 311070), and nonsyndromic X-linked deafness (DFN2, OMIM: 304500). Hearing loss is present in all cases. CMTX5 patients also show peripheral neuropathy and optic atrophy. Arts syndrome includes developmental delay, intellectual disability, ataxia, and susceptibility to infections, in addition to the above three features. Gain-of-function PRPS1 variants result in PRPS superactivity (OMIM: 300661) with hyperuricemia and gout. We report a 6-year-old boy who presented with marked generalized muscular hypotonia, global developmental delay, lack of speech, trunk instability, exercise intolerance, hypomimic face with open mouth, oropharyngeal dysphagia, dysarthria, and frequent upper respiratory tract infections. However, his nerve conduction velocity, audiologic, and funduscopic investigations were normal. A novel hemizygous variant, c.130A > G p.(Ile44Val), was found in the PRPS1 gene by panel sequencing. PRPS activity in erythrocytes was markedly reduced, confirming the pathogenicity of the variant. Serum uric acid and urinary purine and pyrimidine metabolite levels were normal. In conclusion, we present a novel PRPS1 loss-of-function variant in a patient with some clinical features of Arts syndrome, but lacking a major attribute, hearing loss, which is congenital/early-onset in all other reported Arts syndrome patients. In addition, it is important to acknowledge that normal levels of serum and urinary purine and pyrimidine metabolites do not exclude PRPS1-related disorders. We describe a male patient with atypical presentation of Arts syndrome. Our patient harbors a novel loss-of-function variant in the PRPS1 gene. The purine and pyrimidine levels can be normal in patients with decreased PRPS activity.
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Affiliation(s)
- Sanna Puusepp
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Karit Reinson
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
| | - Sander Pajusalu
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia.,Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - André B P van Kuilenburg
- Department of Clinical Chemistry, Cancer Center Amsterdam, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | | | - Jeroen Roelofsen
- Department of Clinical Chemistry, Cancer Center Amsterdam, Amsterdam Gastroenterology & Metabolism, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Werner Stenzel
- Department of Neuropathology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Leibniz Science Campus Chronic Inflammation, Berlin, Germany
| | - Katrin Õunap
- Department of Clinical Genetics, United Laboratories, Tartu University Hospital, Tartu, Estonia.,Department of Clinical Genetics, Institute of Clinical Medicine, Faculty of Medicine, University of Tartu, Tartu, Estonia
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10
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Yang XR, Benson MD, MacDonald IM, Innes AM. A diagnostic approach to syndromic retinal dystrophies with intellectual disability. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:538-570. [PMID: 32918368 DOI: 10.1002/ajmg.c.31834] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/30/2020] [Accepted: 08/05/2020] [Indexed: 12/20/2022]
Abstract
Inherited retinal dystrophies are a group of monogenic disorders that, as a whole, contribute significantly to the burden of ocular disease in both pediatric and adult patients. In their syndromic forms, retinal dystrophies can be observed in association with intellectual disability, frequently alongside other systemic manifestations. There are now over 80 genes implicated in syndromic retinal dystrophies with intellectual disability. Identifying and accurately characterizing these disorders allows the clinician to narrow the differential diagnosis, evaluate for relevant associated features, arrive at a timely and accurate diagnosis, and address both sight-threatening ocular manifestations and morbidity-causing systemic manifestations. The co-occurrence of retinal dystrophy and intellectual disability in an individual can be challenging to investigate, diagnose, and counsel given the considerable phenotypic and genotypic heterogeneity that exists within this broad group of disorders. We performed a review of the current literature and propose an algorithm to facilitate the evaluation, and clinical and mechanistic classification, of these individuals.
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Affiliation(s)
- Xiao-Ru Yang
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Matthew D Benson
- Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada
| | - Ian M MacDonald
- Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada.,Department of Medical Genetics, University of Alberta, Edmonton, Alberta, Canada
| | - A Micheil Innes
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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11
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De Silva SR, Arno G, Robson AG, Fakin A, Pontikos N, Mohamed MD, Bird AC, Moore AT, Michaelides M, Webster AR, Mahroo OA. The X-linked retinopathies: Physiological insights, pathogenic mechanisms, phenotypic features and novel therapies. Prog Retin Eye Res 2020; 82:100898. [PMID: 32860923 DOI: 10.1016/j.preteyeres.2020.100898] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 08/07/2020] [Accepted: 08/21/2020] [Indexed: 02/08/2023]
Abstract
X-linked retinopathies represent a significant proportion of monogenic retinal disease. They include progressive and stationary conditions, with and without syndromic features. Many are X-linked recessive, but several exhibit a phenotype in female carriers, which can help establish diagnosis and yield insights into disease mechanisms. The presence of affected carriers can misleadingly suggest autosomal dominant inheritance. Some disorders (such as RPGR-associated retinopathy) show diverse phenotypes from variants in the same gene and also highlight limitations of current genetic sequencing methods. X-linked disease frequently arises from loss of function, implying potential for benefit from gene replacement strategies. We review X-inactivation and X-linked inheritance, and explore burden of disease attributable to X-linked genes in our clinically and genetically characterised retinal disease cohort, finding correlation between gene transcript length and numbers of families. We list relevant genes and discuss key clinical features, disease mechanisms, carrier phenotypes and novel experimental therapies. We consider in detail the following: RPGR (associated with retinitis pigmentosa, cone and cone-rod dystrophy), RP2 (retinitis pigmentosa), CHM (choroideremia), RS1 (X-linked retinoschisis), NYX (complete congenital stationary night blindness (CSNB)), CACNA1F (incomplete CSNB), OPN1LW/OPN1MW (blue cone monochromacy, Bornholm eye disease, cone dystrophy), GPR143 (ocular albinism), COL4A5 (Alport syndrome), and NDP (Norrie disease and X-linked familial exudative vitreoretinopathy (FEVR)). We use a recently published transcriptome analysis to explore expression by cell-type and discuss insights from electrophysiology. In the final section, we present an algorithm for genes to consider in diagnosing males with non-syndromic X-linked retinopathy, summarise current experimental therapeutic approaches, and consider questions for future research.
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Affiliation(s)
- Samantha R De Silva
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Gavin Arno
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony G Robson
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Ana Fakin
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Ljubljana University Medical Centre, Ljubljana, Slovenia
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Moin D Mohamed
- Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK
| | - Alan C Bird
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, UCSF School of Medicine, San Francisco, CA, USA
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Andrew R Webster
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Omar A Mahroo
- UCL Institute of Ophthalmology, University College London, UK; Moorfields Eye Hospital NHS Foundation Trust, London, UK; Department of Ophthalmology, Guy's & St Thomas' NHS Foundation Trust, London, UK; Section of Ophthalmology, King's College London, UK; Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK.
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12
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PRPS1 loss-of-function variants, from isolated hearing loss to severe congenital encephalopathy: New cases and literature review. Eur J Med Genet 2020; 63:104033. [PMID: 32781272 DOI: 10.1016/j.ejmg.2020.104033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/18/2020] [Accepted: 07/31/2020] [Indexed: 11/21/2022]
Abstract
We describe two sporadic and two familial cases with loss-of-function variants in PRPS1, which is located on the X chromosome and encodes phosphoribosyl pyrophosphate synthetase 1 (PRS-1). We illustrate the clinical variability associated with decreased PRS-1 activity, ranging from mild isolated hearing loss to severe encephalopathy. One of the variants we identified has already been reported with a phenotype similar to our patient's, whereas the other three were unknown. The clinical and biochemical information we provide will hopefully contribute to gain insight into the correlation between genotype and phenotype of this rare condition, both in females and in males. Moreover, our observation of a new family in which hemizygous males display hearing loss without any neurological or ophthalmological symptoms prompts us to suggest analysing PRPS1 in cases of isolated hearing loss. Eventually, PRPS1 variants should be considered as a differential diagnosis of mitochondrial disorders.
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PRPS-Associated Disorders and the Drosophila Model of Arts Syndrome. Int J Mol Sci 2020; 21:ijms21144824. [PMID: 32650483 PMCID: PMC7403961 DOI: 10.3390/ijms21144824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 07/05/2020] [Accepted: 07/05/2020] [Indexed: 11/18/2022] Open
Abstract
While a plethora of genetic techniques have been developed over the past century, modifying specific sequences of the fruit fly genome has been a difficult, if not impossible task. clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 truly redefined molecular genetics and provided new tools to model human diseases in Drosophila melanogaster. This is particularly true for genes whose protein sequences are highly conserved. Phosphoribosyl pyrophosphate synthetase (PRPS) is a rate-limiting enzyme in nucleotide metabolism whose missense mutations are found in several neurological disorders, including Arts syndrome. In addition, PRPS is deregulated in cancer, particularly those that become resistant to cancer therapy. Notably, DrosophilaPRPS shares about 90% protein sequence identity with its human orthologs, making it an ideal gene to study via CRISPR/Cas9. In this review, we will summarize recent findings on PRPS mutations in human diseases including cancer and on the molecular mechanisms by which PRPS activity is regulated. We will also discuss potential applications of Drosophila CRISPR/Cas9 to model PRPS-dependent disorders and other metabolic diseases that are associated with nucleotide metabolism.
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14
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A novel mutation in gene of PRPS1 in a young Chinese woman with X-linked gout: a case report and review of the literature. Clin Rheumatol 2019; 39:949-956. [PMID: 31773495 DOI: 10.1007/s10067-019-04801-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 09/04/2019] [Accepted: 09/26/2019] [Indexed: 10/25/2022]
Abstract
Pyrophosphate synthetase-1(PRS-1) is a crucial enzyme that catalyzes the synthesis of phosphoribosylpyrophosphate (PRPP) with substrate: adenosine triphosphate (ATP) and ribose-5-phophate(R5P) in the de novo pathways of purine and pyrimidine nucleotide synthesis. Mutation in PRPS1 can result in a series of diseases of purine metabolism, which includes PRS-1 superactivity. The common clinical phenotypes are hyperuricemia and hyperuricosuria. We identified a novel missense mutation in X-chromosomal gene PRPS1 in a young Chinese woman while her mother has heterogeneous genotype and phenotype. A 24-year-old Chinese female patient suffered hyperuricemia, gout, and recurrent hyperpyrexia for more than 6 years, and then was diagnosed with hyperandrogenism, insulin resistance (IR), and polycystic ovary syndrome (PCOS). A novel missense mutation, c.521(exon)G>T, p.(Gly174Val) was detected by next-generation sequencing (NGS) and confirmed by Sanger sequencing in the patient and her parents. Interestingly, her mother has the same heterozygous missense mutation but without uric acid overproduction which can be explained by the phenomenon of the skewed X-chromosome inactivation. The substituted amino acid Val for Gly174 is positioned in the pyrophosphate (PPi) binding loop, and this mutation impacts the binding rate of Mg2+-ATP complex to PRS-1, thus the assembling of homodimer is affected by changed Val174 leading to the instability of the allosteric site. Our report highlights the X-linked inheritance of gout in females caused by mutation in PRPS1 accompanied with severe metabolic disorders and recurrent hyperpyrexia.
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15
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Delos Santos K, Kim M, Yergeau C, Jean S, Moon NS. Pleiotropic role of Drosophila phosphoribosyl pyrophosphate synthetase in autophagy and lysosome homeostasis. PLoS Genet 2019; 15:e1008376. [PMID: 31487280 PMCID: PMC6748441 DOI: 10.1371/journal.pgen.1008376] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 09/17/2019] [Accepted: 08/17/2019] [Indexed: 01/07/2023] Open
Abstract
Phosphoribosyl pyrophosphate synthetase (PRPS) is a rate-limiting enzyme whose function is important for the biosynthesis of purines, pyrimidines, and pyridines. Importantly, while missense mutations of PRPS1 have been identified in neurological disorders such as Arts syndrome, how they contribute to neuropathogenesis is still unclear. We identified the Drosophila ortholog of PRPS (dPRPS) as a direct target of RB/E2F in Drosophila, a vital cell cycle regulator, and engineered dPRPS alleles carrying patient-derived mutations. Interestingly, while they are able to develop normally, dPRPS mutant flies have a shortened lifespan and locomotive defects, common phenotypes associated with neurodegeneration. Careful analysis of the fat body revealed that patient-derived PRPS mutations result in profound defects in lipolysis, macroautophagy, and lysosome function. Significantly, we show evidence that the nervous system of dPRPS mutant flies is affected by these defects. Overall, we uncovered an unexpected link between nucleotide metabolism and autophagy/lysosome function, providing a possible mechanism by which PRPS-dysfunction contributes to neurological disorders.
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Affiliation(s)
- Keemo Delos Santos
- Department of Biology, Developmental Biology Research Initiative, McGill University, Montreal, Quebec, Canada
| | - Minhee Kim
- Department of Biology, Developmental Biology Research Initiative, McGill University, Montreal, Quebec, Canada
| | - Christine Yergeau
- Department of Biology, Developmental Biology Research Initiative, McGill University, Montreal, Quebec, Canada
| | - Steve Jean
- Faculté de Médecine et des Sciences de la Santé, Département d’Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Nam-Sung Moon
- Department of Biology, Developmental Biology Research Initiative, McGill University, Montreal, Quebec, Canada
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16
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Meng L, Wang K, Lv H, Wang Z, Zhang W, Yuan Y. A novel mutation in PRPS1 causes X-linked Charcot-Marie-Tooth disease-5. Neuropathology 2019; 39:342-347. [PMID: 31434166 DOI: 10.1111/neup.12589] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/16/2019] [Accepted: 06/28/2019] [Indexed: 12/20/2022]
Abstract
X-linked Charcot-Marie-Tooth disease-5 (CMTX5) is a rare hereditary disorder caused by mutations in the gene for phosphoribosyl pyrophosphate synthetase-1 (PRPS1). We investigated a boy with a novel PRPS1 mutation (c.334G>C, p.V112L) via genetic, neuropathological and enzymatic tests. The proband was a 13-year-old boy with congenital non-syndromic sensorineural deafness. At 3 year old, he developed progressive distal weakness of all limbs with muscle atrophy of both hands and shanks. Nerve conduction study revealed the loss of sensory nerve action potentials, and slowing down of motor nerve conduction velocities with a decrease of amplitudes of compound motor action potentials. Visual evoked potentials and brainstem auditory evoked potentials were not bilaterally evocable. Sural biopsy proved the loss of myelinated nerve fibers, with axonal degeneration, regenerating clusters and onion bulbs. Enzymatically, PRPS1 activity was close to zero in the proband and mildly reduced in his mother, compared with controls. To our knowledge, this is the first report of CMTX5 in a Chinese population. The genetic finding has expanded the genotypic spectrum of PRPS1 mutations.
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Affiliation(s)
- Lingchao Meng
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Kang Wang
- Peking University-Tsinghua University-National Institute of Biological Sciences Joint Graduate Program, School of Life Sciences, Tsinghua University, Beijing, China
| | - He Lv
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, China
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17
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Li J, Ye J, Zhu S, Cui H. Down-Regulation of Phosphoribosyl Pyrophosphate Synthetase 1 Inhibits Neuroblastoma Cell Proliferation. Cells 2019; 8:cells8090955. [PMID: 31443513 PMCID: PMC6770549 DOI: 10.3390/cells8090955] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 08/17/2019] [Accepted: 08/20/2019] [Indexed: 01/09/2023] Open
Abstract
Phosphoribosyl pyrophosphate synthetase 1 (PRPS1) is a key enzyme in de novo nucleotide synthesis and nucleotide salvage synthesis pathways that are critical for purine and pyrimidine biosynthesis. Abnormally high expression of PRPS1 can cause many diseases, including hearing loss, hypotonia, and ataxia, in addition to being associated with neuroblastoma. However, the role of PRPS1 in neuroblastoma is still unclear. In this study, we found that PRPS1 was commonly expressed in neuroblastoma cells and was closely related to poor prognosis for cancer. Furthermore, down-regulation of PRPS1 inhibited neuroblastoma cell proliferation and tumor growth in vitro and in vivo via disturbing DNA synthesis. This study provides new insights into the treatment of neuroblastoma patients and new targets for drug development.
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Affiliation(s)
- Jifu Li
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
- College of Biotechnology, Southwest University, Chongqing 400715, China
| | - Junhong Ye
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China
- Biological Science Research Center, Southwest University, Chongqing 400715, China
| | - Shunqin Zhu
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China.
- School of Life Sciences, Southwest University, Chongqing 400715, China.
| | - Hongjuan Cui
- State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing 400715, China.
- Engineering Research Center for Cancer Biomedical and Translational Medicine, Southwest University, Chongqing 400715, China.
- Chongqing Engineering and Technology Research Center for Silk Biomaterials and Regenerative Medicine, Southwest University, Chongqing 400715, China.
- Cancer Center, Medical Research Institute, Southwest University, Chongqing 400715, China.
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18
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Fiorentino A, Fujinami K, Arno G, Robson AG, Pontikos N, Arasanz Armengol M, Plagnol V, Hayashi T, Iwata T, Parker M, Fowler T, Rendon A, Gardner JC, Henderson RH, Cheetham ME, Webster AR, Michaelides M, Hardcastle AJ. Missense variants in the X-linked gene PRPS1 cause retinal degeneration in females. Hum Mutat 2018; 39:80-91. [PMID: 28967191 DOI: 10.1002/humu.23349] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 09/15/2017] [Accepted: 09/21/2017] [Indexed: 12/14/2022]
Abstract
Retinal dystrophies are a heterogeneous group of disorders of visual function leading to partial or complete blindness. We report the genetic basis of an unusual retinal dystrophy in five families with affected females and no affected males. Heterozygous missense variants were identified in the X-linked phosphoribosyl pyrophosphate synthetase 1 (PRPS1) gene: c.47C > T, p.(Ser16Phe); c.586C > T, p.(Arg196Trp); c.641G > C, p.(Arg214Pro); and c.640C > T, p.(Arg214Trp). Missense variants in PRPS1 are usually associated with disease in male patients, including Arts syndrome, Charcot-Marie-Tooth, and nonsyndromic sensorineural deafness. In our study families, affected females manifested a retinal dystrophy with interocular asymmetry. Three unrelated females from these families had hearing loss leading to a diagnosis of Usher syndrome. Other neurological manifestations were also observed in three individuals. Our data highlight the unexpected X-linked inheritance of retinal degeneration in females caused by variants in PRPS1 and suggest that tissue-specific skewed X-inactivation or variable levels of pyrophosphate synthetase-1 deficiency are the underlying mechanism(s). We speculate that the absence of affected males in the study families suggests that some variants may be male embryonic lethal when inherited in the hemizygous state. The unbiased nature of next-generation sequencing enables all possible modes of inheritance to be considered for association of gene variants with novel phenotypic presentation.
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Affiliation(s)
| | - Kaoru Fujinami
- UCL Institute of Ophthalmology, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
- National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Center, Tokyo, Japan
- Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan
| | - Gavin Arno
- UCL Institute of Ophthalmology, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
| | - Anthony G Robson
- UCL Institute of Ophthalmology, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, London, United Kingdom
- UCL Genetics Institute, London, United Kingdom
| | | | | | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Takeshi Iwata
- National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Center, Tokyo, Japan
| | - Matthew Parker
- Genomics England, Queen Mary University of London, London, United Kingdom
- Sheffield Diagnostic Genetics Service, Sheffield Children's Hospital, Sheffield, United Kingdom
| | - Tom Fowler
- Genomics England, Queen Mary University of London, London, United Kingdom
| | - Augusto Rendon
- Genomics England, Queen Mary University of London, London, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
| | | | - Robert H Henderson
- Moorfields Eye Hospital, London, United Kingdom
- Great Ormond Street Hospital for Children, Great Ormond Street, London, United Kingdom
| | | | - Andrew R Webster
- UCL Institute of Ophthalmology, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
| | - Michel Michaelides
- UCL Institute of Ophthalmology, London, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
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19
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Kim SY, Kim AR, Kim NKD, Lee C, Han JH, Kim MY, Jeon EH, Park WY, Mittal R, Yan D, Liu XZ, Choi BY. Functional characterization of a novel loss-of-function mutation of PRPS1 related to early-onset progressive nonsyndromic hearing loss in Koreans (DFNX1): Potential implications on future therapeutic intervention. J Gene Med 2017; 18:353-358. [PMID: 27886419 DOI: 10.1002/jgm.2935] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 11/22/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The symptoms of phosphoribosyl pyrophosphate synthetase 1 (PRPS1) deficiency diseases have been reported to be alleviated by medication. In the present study, we report biochemical data that favor PRPS1 deficiency-related hearing loss as a potential target for pharmaceutical treatment. METHODS We recruited 42 probands from subjects aged less than 15 years with a moderate degree of nonsyndromic autosomal-recessive or sporadic sensorineural hearing loss (SNHL) in at least one side. Molecular genetic testing, including targeted exome sequencing (TES) of 129 genes for deafness, and in silico prediction were performed. RESULTS A strong candidate variant (p.A82P) of PRPS1 is co-segregated with SNHL in X-linked recessive inheritance from one Korean multiplex SNHL family. Subsequent measurement of in vitro enzymatic activities of PRPS1 from erythrocytes of affected and unaffected family members, as well as unrelated normal controls, confirmed a pathogenic role of this variant. In detail, compared to normal hearing controls (0.23-0.26 nmol/ml/h), the proband, the affected sibling and their normal hearing mother demonstrated a significantly decreased PRPS1 enzymatic activity (0.07, 0.03 and 0.11 nmol/ml/h, respectively). This novel loss-of-function mutation of PRPS1 (p.A82P) is the ninth and sixth most reported mutation in the world and in Asia, respectively. CONCLUSIONS DFNX1 was found to account for approximately 2.4% (1/42) of moderate SNHL in a Korean pediatric population. Confirmation of PRPS1 activity deficiency and an audiologic phenotype that initially begins in a milder form of SNHL, as in our family, should indicate the need for rigorous genetic screening as early as possible.
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Affiliation(s)
- So Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, CHA Bundang Medical Center, CHA University, Seongnam, South Korea
| | - Ah Reum Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
| | - Nayoung K D Kim
- Samsung Genome Institute, Samsung Medical Center, Seoul, South Korea
| | - Chung Lee
- Samsung Genome Institute, Samsung Medical Center, Seoul, South Korea.,Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Suwon, South Korea
| | - Jin Hee Han
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea
| | - Min Young Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea
| | - Eun-Hee Jeon
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea
| | - Woong-Yang Park
- Samsung Genome Institute, Samsung Medical Center, Seoul, South Korea.,Department of Molecular Cell Biology, School of Medicine, Sungkyunkwan University, Seoul, South Korea
| | - Rahul Mittal
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Denise Yan
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Xue Zhong Liu
- Department of Otolaryngology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Byung Yoon Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, South Korea.,Wide River Institute of Immunology, Seoul National University College of Medicine, Hongcheon, South Korea
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20
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Porrmann J, Betcheva-Krajcir E, Di Donato N, Kahlert AK, Schallner J, Rump A, Schröck E, Dobritzsch D, Roelofsen J, van Kuilenburg ABP, Tzschach A. Novel PRPS1 gain-of-function mutation in a patient with congenital hyperuricemia and facial anomalies. Am J Med Genet A 2017; 173:2736-2742. [PMID: 28742244 DOI: 10.1002/ajmg.a.38359] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 05/10/2017] [Accepted: 06/21/2017] [Indexed: 11/08/2022]
Abstract
Phosphoribosylpyrophosphate synthetase (PRPPS) superactivity (OMIM 300661) is a rare inborn error of purine metabolism that is caused by gain-of-function mutations in the X-chromosomal gene PRPS1 (Xq22.3). Clinical characteristics include congenital hyperuricemia and hyperuricosuria, gouty arthritis, urolithiasis, developmental delay, hypotonia, recurrent infections, short stature, and hearing loss. Only eight families with PRPPS superactivity and PRPS1 gain-of-function mutations have been reported to date. We report on a 7-year-old boy with congenital hyperuricemia, urolithiasis, developmental delay, short stature, hypospadias, and facial dysmorphisms. His mother also suffered from hyperuricemia that was diagnosed at age 13 years. A novel PRPS1 missense mutation (c.573G>C, p.[Leu191Phe]) was detected in the proband and his mother. Enzyme activity analysis confirmed superactivity of PRPP synthetase. Analysis of the crystal structure of human PRPPS suggests that the Leu191Phe mutation affects the architecture of both allosteric sites, thereby preventing the allosteric inhibition of the enzyme. The family reported here broadens the clinical spectrum of PRPPS superactivity and indicates that this rare metabolic disorder might be associated with a recognizable facial gestalt.
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Affiliation(s)
- Joseph Porrmann
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | | | - Nataliya Di Donato
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Anne-Karin Kahlert
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Jens Schallner
- Children's hospital, Universitätsklinikum Carl Gustav Carus, Dresden, Germany
| | - Andreas Rump
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Evelin Schröck
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Doreen Dobritzsch
- Department of Chemistry, Biomedical Center, Uppsala University, Uppsala, Sweden
| | - Jeroen Roelofsen
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Academic Medical Centre, Emma Children's Hospital, University of Amsterdam, Amsterdam, The Netherlands
| | - André B P van Kuilenburg
- Department of Clinical Chemistry, Laboratory Genetic Metabolic Diseases, Academic Medical Centre, Emma Children's Hospital, University of Amsterdam, Amsterdam, The Netherlands
| | - Andreas Tzschach
- Institut für Klinische Genetik, Technische Universität Dresden, Dresden, Germany
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21
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Chesmore KN, Bartlett J, Cheng C, Williams SM. Complex Patterns of Association between Pleiotropy and Transcription Factor Evolution. Genome Biol Evol 2016; 8:3159-3170. [PMID: 27635052 PMCID: PMC5174740 DOI: 10.1093/gbe/evw228] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pleiotropy has been claimed to constrain gene evolution but specific mechanisms and extent of these constraints have been difficult to demonstrate. The expansion of molecular data makes it possible to investigate these pleiotropic effects. Few classes of genes have been characterized as intensely as human transcription factors (TFs). We therefore analyzed the evolutionary rates of full TF proteins, along with their DNA binding domains and protein-protein interacting domains (PID) in light of the degree of pleiotropy, measured by the number of TF-TF interactions, or the number of DNA-binding targets. Data were extracted from the ENCODE Chip-Seq dataset, the String v 9.2 database, and the NHGRI GWAS catalog. Evolutionary rates of proteins and domains were calculated using the PAML CodeML package. Our analysis shows that the numbers of TF-TF interactions and DNA binding targets associated with constrained gene evolution; however, the constraint caused by the number of DNA binding targets was restricted to the DNA binding domains, whereas the number of TF-TF interactions constrained the full protein and did so more strongly. Additionally, we found a positive correlation between the number of protein-PIDs and the evolutionary rates of the protein-PIDs. These findings show that not only does pleiotropy associate with constrained protein evolution but the constraint differs by domain function. Finally, we show that GWAS associated TF genes are more highly pleiotropic : The GWAS data illustrates that mutations in highly pleiotropic genes are more likely to be associated with disease phenotypes.
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Affiliation(s)
- Kevin N Chesmore
- Department of Genetics, Geisel School of Medicine, Dartmouth College, Hanover, NH
| | - Jacquelaine Bartlett
- Department of Genetics, Geisel School of Medicine, Dartmouth College, Hanover, NH
| | - Chao Cheng
- Department of Genetics, Geisel School of Medicine, Dartmouth College, Hanover, NH
| | - Scott M Williams
- Department of Genetics, Geisel School of Medicine, Dartmouth College, Hanover, NH
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Additive reductions in zebrafish PRPS1 activity result in a spectrum of deficiencies modeling several human PRPS1-associated diseases. Sci Rep 2016; 6:29946. [PMID: 27425195 PMCID: PMC4947902 DOI: 10.1038/srep29946] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Accepted: 06/27/2016] [Indexed: 01/08/2023] Open
Abstract
Phosphoribosyl pyrophosphate synthetase-1 (PRPS1) is a key enzyme in nucleotide biosynthesis, and mutations in PRPS1 are found in several human diseases including nonsyndromic sensorineural deafness, Charcot-Marie-Tooth disease-5, and Arts Syndrome. We utilized zebrafish as a model to confirm that mutations in PRPS1 result in phenotypic deficiencies in zebrafish similar to those in the associated human diseases. We found two paralogs in zebrafish, prps1a and prps1b and characterized each paralogous mutant individually as well as the double mutant fish. Zebrafish prps1a mutants and prps1a;prps1b double mutants showed similar morphological phenotypes with increasingly severe phenotypes as the number of mutant alleles increased. Phenotypes included smaller eyes and reduced hair cell numbers, consistent with the optic atrophy and hearing impairment observed in human patients. The double mutant also showed abnormal development of primary motor neurons, hair cell innervation, and reduced leukocytes, consistent with the neuropathy and recurrent infection of the human patients possessing the most severe reductions of PRPS1 activity. Further analyses indicated the phenotypes were associated with a prolonged cell cycle likely resulting from reduced nucleotide synthesis and energy production in the mutant embryos. We further demonstrated the phenotypes were caused by delays in the tissues most highly expressing the prps1 genes.
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Flannick J, Johansson S, Njølstad PR. Common and rare forms of diabetes mellitus: towards a continuum of diabetes subtypes. Nat Rev Endocrinol 2016; 12:394-406. [PMID: 27080136 DOI: 10.1038/nrendo.2016.50] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Insights into the genetic basis of type 2 diabetes mellitus (T2DM) have been difficult to discern, despite substantial research. More is known about rare forms of diabetes mellitus, several of which share clinical and genetic features with the common form of T2DM. In this Review, we discuss the extent to which the study of rare and low-frequency mutations in large populations has begun to bridge the gap between rare and common forms of diabetes mellitus. We hypothesize that the perceived division between these diseases might be due, in part, to the historical ascertainment bias of genetic studies, rather than a clear distinction between disease pathophysiologies. We also discuss possible implications of a new model for the genetic basis of diabetes mellitus subtypes, where the boundary between subtypes becomes blurred.
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Affiliation(s)
- Jason Flannick
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, 415 Main Street, Cambridge, Massachusetts 02142, USA
- Center for Human Genetic Research, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA
| | - Stefan Johansson
- K.G. Jebsen Center for Diabetes Research, The Department of Clinical Science, University of Bergen, Jonas Lies veg 87, N-5020 Bergen, Norway
- Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Jonas Lies veg 65, N-5021 Bergen, Norway
| | - Pål R Njølstad
- K.G. Jebsen Center for Diabetes Research, The Department of Clinical Science, University of Bergen, Jonas Lies veg 87, N-5020 Bergen, Norway
- Department of Pediatrics, Haukeland University Hospital, Jonas Lies veg 65, N-5021 Bergen, Norway
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24
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Genetic Testing for Deaf and Hard of Hearing Individuals: Genetic Counseling. CURRENT GENETIC MEDICINE REPORTS 2016. [DOI: 10.1007/s40142-016-0089-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
Whole-exome sequencing has emerged as a fast and effective tool for the elucidation of genetic defects underlying both rare and common human diseases. Increased availability and decreased costs of next-generation sequencing have enabled investigators to use this approach not only in individual patients with rare diseases, but also to screen large cohorts or populations for the genetic determinants of diseases. Within the field of endocrinology, exome sequencing has led to major advancements in our understanding of many disorders including adrenal disease, growth and puberty disorders and type 2 diabetes mellitus, as well as a multitude of rare genetic syndromes with prominent endocrine involvement. In this Review, we provide an overview of these new insights and discuss the role that exome sequencing is expected to have in endocrine research and future clinical practice.
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Affiliation(s)
- Christiaan de Bruin
- Cincinnati Children's Hospital Medical Center, Division of Endocrinology, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Andrew Dauber
- Cincinnati Children's Hospital Medical Center, Division of Endocrinology, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
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Mutations in PRPS1 causing syndromic or nonsyndromic hearing impairment: intrafamilial phenotypic variation complicates genetic counseling. Pediatr Res 2015; 78:97-102. [PMID: 25785835 DOI: 10.1038/pr.2015.56] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Accepted: 12/06/2014] [Indexed: 11/08/2022]
Abstract
BACKGROUND PRPS1 encodes isoform I of phosphoribosylpyrophosphate synthetase (PRS-I), a key enzyme in nucleotide biosynthesis. Different missense mutations in PRPS1 cause a variety of disorders that include PRS-I superactivity, nonsyndromic sensorineural hearing impairment, Charcot-Marie-Tooth disease, and Arts syndrome. It has been proposed that each mutation would result in a specific phenotype, depending on its effects on the structure and function of the enzyme. METHODS Thirteen Spanish unrelated families segregating X-linked hearing impairment were screened for PRPS1 mutations by Sanger sequencing. In two positive pedigrees, segregation of mutations was studied, and clinical data from affected subjects were compared. RESULTS We report two novel missense mutations in PRPS1, p.Ile275Thr and p.Gly306Glu, which were found in the propositi of two unrelated Spanish families, both subjects presenting with nonsyndromic hearing impairment. Further investigation revealed syndromic features in other hemizygous carriers from one of the pedigrees. Sequencing of genes that are functionally related to PRPS1 did not reveal any candidate variant that might act as a phenotype modifier. CONCLUSION This case of intrafamilial phenotypic variation associated with a single PRPS1 mutation complicates the genotype-phenotype correlations, which makes genetic counseling of mutation carriers difficult because of the wide spectrum of severity of the associated disorders.
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Association of PRPS1 Mutations with Disease Phenotypes. DISEASE MARKERS 2015; 2015:127013. [PMID: 26089585 PMCID: PMC4458296 DOI: 10.1155/2015/127013] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 05/06/2015] [Indexed: 01/01/2023]
Abstract
Phosphoribosylpyrophosphate synthetase 1 (PRPS1) codes for PRS-I enzyme that catalyzes the first step of nucleotide synthesis. PRPS1 gene mutations have been implicated in a number of human diseases. Recently, new mutations in PRPS1 have been identified that have been associated with novel phenotypes like diabetes insipidus expanding the spectrum of PRPS1-related diseases. The purpose of this review is to evaluate current literature on PRPS1-related syndromes and summarize potential therapies. The overexpression of PRPS1 results in PRS-I superactivity resulting in purine overproduction. Patients with PRS-I superactivity demonstrate uric acid overproduction, hypotonia, ataxia, neurodevelopment abnormalities, and postlingual hearing impairment. On the other hand, decreased activity leads to X-linked nonsyndromic sensorineural deafness (DFNX-2), Charcot-Marie-Tooth disease-5 (CMTX5), and Arts syndrome depending on the residual activity of PRS-I. Mild PRS-I deficiency (DFNX-2) results in non-syndromic progressive hearing loss whereas moderate PRS-I deficiency (CMTX5) and severe PRS-I deficiency (Arts syndrome) present with peripheral or optic neuropathy, prelingual progressive sensorineural hearing loss, and central nervous system impairment. Currently, purine replacement via S-adenosylmethionine (SAM) supplementation in patients with Arts syndrome appears to improve their condition. This suggests that SAM supplementation can alleviate symptoms of PRPS1 deficient patients and open new avenues of therapeutic intervention.
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28
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Almoguera B, He S, Corton M, Fernandez-San Jose P, Blanco-Kelly F, López-Molina MI, García-Sandoval B, Del Val J, Guo Y, Tian L, Liu X, Guan L, Torres RJ, Puig JG, Hakonarson H, Xu X, Keating B, Ayuso C. Expanding the phenotype of PRPS1 syndromes in females: neuropathy, hearing loss and retinopathy. Orphanet J Rare Dis 2014; 9:190. [PMID: 25491489 PMCID: PMC4272780 DOI: 10.1186/s13023-014-0190-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Accepted: 11/11/2014] [Indexed: 11/22/2022] Open
Abstract
Background Phosphoribosyl pyrophosphate synthetase (PRS) I deficiency is a rare medical condition caused by missense mutations in PRPS1 that lead to three different phenotypes: Arts Syndrome (MIM 301835), X-linked Charcot-Marie-Tooth (CMTX5, MIM 311070) or X-linked non-syndromic sensorineural deafness (DFN2, MIM 304500). All three are X-linked recessively inherited and males affected display variable degree of central and peripheral neuropathy. We applied whole exome sequencing to a three-generation family with optic atrophy followed by retinitis pigmentosa (RP) in all three cases, and ataxia, progressive peripheral neuropathy and hearing loss with variable presentation. Methods Whole exome sequencing was performed in two affecteds and one unaffected member of the family. Sanger sequencing was used to validate and segregate the 12 candidate mutations in the family and to confirm the absence of the novel variant in PRPS1 in 191 controls. The pathogenic role of the novel mutation in PRPS1 was assessed in silico and confirmed by enzymatic determination of PRS activity, mRNA expression and sequencing, and X-chromosome inactivation. Results A novel missense mutation was identified in PRPS1 in the affected females. Age of onset, presentation and severity of the phenotype are highly variable in the family: both the proband and her mother have neurological and ophthalmological symptoms, whereas the phenotype of the affected sister is milder and currently confined to the eye. Moreover, only the proband displayed a complete lack of expression of the wild type allele in leukocytes that seems to correlate with the degree of PRS deficiency and the severity of the phenotype. Interestingly, optic atrophy and RP are the only common manifestations to all three females and the only phenotype correlating with the degree of enzyme deficiency. Conclusions These results are in line with recent evidence of the existence of intermediate phenotypes in PRS-I deficiency syndromes and demonstrate that females can exhibit a disease phenotype as severe and complex as their male counterparts. Electronic supplementary material The online version of this article (doi:10.1186/s13023-014-0190-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Berta Almoguera
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
| | - Sijie He
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China. .,BGI-Shenzhen, Shenzhen, 518083, China.
| | - Marta Corton
- Department of Genetics and Genomics, IIS-Fundación Jiménez Díaz University Hospital (IISFJD, UAM), 28040, Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain.
| | - Patricia Fernandez-San Jose
- Department of Genetics and Genomics, IIS-Fundación Jiménez Díaz University Hospital (IISFJD, UAM), 28040, Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain.
| | - Fiona Blanco-Kelly
- Department of Genetics and Genomics, IIS-Fundación Jiménez Díaz University Hospital (IISFJD, UAM), 28040, Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain.
| | - Maria Isabel López-Molina
- Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain. .,Department of Ophthalmology, Fundación Jiménez Díaz, 28040, Madrid, Spain.
| | - Blanca García-Sandoval
- Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain. .,Department of Ophthalmology, Fundación Jiménez Díaz, 28040, Madrid, Spain.
| | - Javier Del Val
- Department of Neurology, Fundación Jiménez Díaz, 28040, Madrid, Spain.
| | - Yiran Guo
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
| | - Lifeng Tian
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
| | | | | | - Rosa J Torres
- Department of Biochemistry, La Paz University Hospital IdiPaz, Madrid, 28046, Spain.
| | - Juan G Puig
- Department of Internal Medicine, Metabolic-Vascular Unit, La Paz University Hospital IdiPaz, Madrid, 28046, Spain.
| | - Hakon Hakonarson
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
| | - Xun Xu
- BGI-Shenzhen, Shenzhen, 518083, China. .,The Guangdong Enterprise Key Laboratory of Human Disease Genomics, Shenzhen, China.
| | - Brendan Keating
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
| | - Carmen Ayuso
- Department of Genetics and Genomics, IIS-Fundación Jiménez Díaz University Hospital (IISFJD, UAM), 28040, Madrid, Spain. .,Center for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain.
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