1
|
Morgan NV, Yngvadottir B, O'Driscoll M, Clark GR, Walsh D, Martin E, Tee L, Reid E, Titheradge HL, Maher ER. Evidence that autosomal recessive spastic cerebral palsy-1 (CPSQ1) is caused by a missense variant in HPDL. Brain Commun 2021; 3:fcab002. [PMID: 33634263 PMCID: PMC7892364 DOI: 10.1093/braincomms/fcab002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/15/2020] [Accepted: 11/26/2020] [Indexed: 01/05/2023] Open
Abstract
A subset of individuals diagnosed with cerebral palsy will have an underlying genetic diagnosis. Previously, a missense variant in GAD1 was described as a candidate mutation in a single family diagnosed with autosomal recessive spastic cerebral palsy-1 (CPSQ1; OMIM 603513). Following the ascertainment of a further branch of the CPSQ1 kindred, we found that the previously reported GAD1 variant did not segregate with the neurological disease phenotype in the recently ascertained branch of the kindred. Following genetic linkage studies to map autozygous regions and whole-exome sequencing, a missense variant (c.527 T > C; p. Leu176Pro, rs773333490) in the HPDL gene was detected and found to segregate with disease status in both branches of the kindred. HPDL encodes a 371-amino acid protein (4-Hydroxyphenylpyruvate Dioxygenase Like) that localizes to mitochondria but whose function is uncertain. Recently, biallelic loss of function variants and missense substitution-causing variants in HPDL were reported to cause a childhood onset progressive spastic movement disorder with a variable presentation. These findings suggest that HPDL-related neurological disease may mimic spastic cerebral palsy and that GAD1 should not be included in diagnostic gene panels for inherited cerebral palsy.
Collapse
Affiliation(s)
- Neil V Morgan
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Bryndis Yngvadottir
- Department of Medical Genetics, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, UK
| | - Mary O'Driscoll
- West Midlands Regional Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's NHS Trust, Birmingham B15 2TG, UK
| | - Graeme R Clark
- Department of Medical Genetics, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, UK
| | - Diana Walsh
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Trust, Birmingham B15 2TG, UK
| | - Ezequiel Martin
- Department of Medical Genetics, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, UK.,Oncology Department, Cancer Molecular Diagnostics Laboratory, University of Cambridge, Cambridge CB2 0XZ, UK
| | - Louise Tee
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Evan Reid
- Department of Medical Genetics, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, UK.,Cambridge Institute of Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Hannah L Titheradge
- West Midlands Regional Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's NHS Trust, Birmingham B15 2TG, UK
| | - Eamonn R Maher
- Department of Medical Genetics, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, UK
| |
Collapse
|
2
|
Damgaard RB, Jolin HE, Allison MED, Davies SE, Titheradge HL, McKenzie ANJ, Komander D. OTULIN protects the liver against cell death, inflammation, fibrosis, and cancer. Cell Death Differ 2020; 27:1457-1474. [PMID: 32231246 PMCID: PMC7206033 DOI: 10.1038/s41418-020-0532-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 12/13/2022] Open
Abstract
Methionine-1 (M1)-linked polyubiquitin chains conjugated by the linear ubiquitin chain assembly complex (LUBAC) control NF-κB activation, immune homoeostasis, and prevents tumour necrosis factor (TNF)-induced cell death. The deubiquitinase OTULIN negatively regulates M1-linked polyubiquitin signalling by removing the chains conjugated by LUBAC, and OTULIN deficiency causes OTULIN-related autoinflammatory syndrome (ORAS) in humans. However, the cellular pathways and physiological functions controlled by OTULIN remain poorly understood. Here, we show that OTULIN prevents development of liver disease in mice and humans. In an ORAS patient, OTULIN deficiency caused spontaneous and progressive steatotic liver disease at 10-13 months of age. Similarly, liver-specific deletion of OTULIN in mice leads to neonatally onset steatosis and hepatitis, akin to the ORAS patient. OTULIN deficiency triggers metabolic alterations, apoptosis, and inflammation in the liver. In mice, steatosis progresses to steatohepatitis, fibrosis and pre-malignant tumour formation by 8 weeks of age, and by the age of 7-12 months the phenotype has advanced to malignant hepatocellular carcinoma. Surprisingly, the pathology in OTULIN-deficient livers is independent of TNFR1 signalling. Instead, we find that steatohepatitis in OTULIN-deficient livers is associated with aberrant mTOR activation, and inhibition of mTOR by rapamycin administration significantly reduces the liver pathology. Collectively, our results reveal that OTULIN is critical for maintaining liver homoeostasis and suggest that M1-linked polyubiquitin chains may play a role in regulation of mTOR signalling and metabolism in the liver.
Collapse
Affiliation(s)
- Rune Busk Damgaard
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK. .,Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, 2800 Kgs, Lyngby, Denmark.
| | - Helen E Jolin
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Michael E D Allison
- Liver Unit, Department of Medicine, Cambridge Biomedical Research Centre, Cambridge University Hospitals NHS Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Susan E Davies
- Department of Histopathology, Cambridge University Hospitals NHS Foundation Trust, Cambridge, CB2 0QQ, UK
| | - Hannah L Titheradge
- Birmingham Women's and Children's National Health Service Foundation Trust, Mindelsohn Way, Birmingham, B15 2TG, UK
| | - Andrew N J McKenzie
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - David Komander
- Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge, CB2 0QH, UK. .,Ubiquitin Signalling Division, The Walter and Eliza Hall Institute of Medical Research, Royal Parade, Parkville, Melbourne, VIC, 3052, Australia. .,Department of Medical Biology, The University of Melbourne, Melbourne, VIC, 3010, Australia.
| |
Collapse
|