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Dehnavi AZ, Bemanalizadeh M, Kahani SM, Ashrafi MR, Rohani M, Toosi MB, Heidari M, Hosseinpour S, Amini B, Zokaei S, Rezaei Z, Aryan H, Amanat M, Vahidnezhad H, Mohammadi P, Garshasbi M, Tavasoli AR. Phenotype and genotype heterogeneity of PLA2G6-associated neurodegeneration in a cohort of pediatric and adult patients. Orphanet J Rare Dis 2023; 18:177. [PMID: 37403138 DOI: 10.1186/s13023-023-02780-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 06/18/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Phospholipase-associated neurodegeneration (PLAN) caused by mutations in the PLA2G6 gene is a rare neurodegenerative disorder that presents with four sub-groups. Infantile neuroaxonal dystrophy (INAD) and PLA2G6-related dystonia-parkinsonism are the main two subtypes. In this cohort, we reviewed clinical, imaging, and genetic features of 25 adult and pediatric patients harboring variants in the PLA2G6. METHODS An extensive review of the patients' data was carried out. Infantile Neuroaxonal Dystrophy Rating Scale (INAD-RS) was used for evaluating the severity and progression of INAD patients. Whole-exome sequencing was used to determine the disease's underlying etiology followed by co-segregation analysis using Sanger sequencing. In silico prediction analysis based on the ACMG recommendation was used to assess the pathogenicity of genetic variants. We aimed to survey a genotype-genotype correlation in PLA2G6 considering all reported disease-causing variants in addition to our patients using the HGMD database and the chi-square statistical approach. RESULTS Eighteen cases of INAD and 7 cases of late-onset PLAN were enrolled. Among 18 patients with INAD, gross motor regression was the most common presenting symptom. Considering the INAD-RS total score, the mean rate of progression was 0.58 points per month of symptoms (Standard error 0.22, lower 95% - 1.10, and upper 95% - 0.15). Sixty percent of the maximum potential loss in the INAD-RS had occurred within 60 months of symptom onset in INAD patients. Among seven adult cases of PLAN, hypokinesia, tremor, ataxic gate, and cognitive impairment were the most frequent clinical features. Various brain imaging abnormalities were also observed in 26 imaging series of these patients with cerebellar atrophy being the most common finding in more than 50%. Twenty unique variants in 25 patients with PLAN were detected including nine novel variants. Altogether, 107 distinct disease-causing variants from 87 patient were analyzed to establish a genotype-phenotype correlation. The P value of the chi-square test did not indicate a significant relationship between age of disease onset and the distribution of reported variants on PLA2G6. CONCLUSION PLAN presents with a wide spectrum of clinical symptoms from infancy to adulthood. PLAN should be considered in adult patients with parkinsonism or cognition decline. Based on the current knowledge, it is not possible to foresee the age of disease onset based on the identified genotype.
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Affiliation(s)
- Ali Zare Dehnavi
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Bemanalizadeh
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
- Child Growth and Development Research Center, Research Institute for Primordial Prevention of Non-Communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Seyyed Mohammad Kahani
- Faculty of Medical Sciences, Department of Medical Genetics, Tarbiat Modares University, Tehran, Iran
| | - Mahmoud Reza Ashrafi
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Rohani
- Skull Base Research Center, The Five Senses Health Institute, Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
- Department of Neurology, Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Mehran Beiraghi Toosi
- Department of Pediatrics, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Neuroscience Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Morteza Heidari
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Sareh Hosseinpour
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Behnam Amini
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Shaghayegh Zokaei
- Dr. Farhud's Genetic Clinic, Tehran, Iran
- School of Advanced Medical Science, Islamic Azad University, Tehran, Iran
| | - Zahra Rezaei
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Hajar Aryan
- Dr. Farhud's Genetic Clinic, Tehran, Iran
- National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Man Amanat
- Department of Neurology, Johns Hopkins Medicine, Baltimore, MD, USA
| | - Hassan Vahidnezhad
- Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA
- Department of Dermatology and Cutaneous Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Pouria Mohammadi
- Faculty of Medical Sciences, Department of Medical Genetics, Tarbiat Modares University, Tehran, Iran
- Pediatric Neurology Division, Children's Medical Center, Pediatrics Center of Excellence, Ataxia Clinic, Tehran University of Medical Sciences, Tehran, Iran
| | - Masoud Garshasbi
- Faculty of Medical Sciences, Department of Medical Genetics, Tarbiat Modares University, Tehran, Iran.
| | - Ali Reza Tavasoli
- Department of Pediatrics, Division of Pediatric Neurology, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
- Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, PA, USA.
- Pediatric Neurology Division, Children's Medical Center, Pediatrics Center of Excellence, Ataxia Clinic, Tehran University of Medical Sciences, Tehran, Iran.
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Lin G, Tepe B, McGrane G, Tipon RC, Croft G, Panwala L, Hope A, Liang AJH, Zuo Z, Byeon SK, Wang L, Pandey A, Bellen HJ. Exploring therapeutic strategies for infantile neuronal axonal dystrophy ( INAD/PARK14). eLife 2023; 12:82555. [PMID: 36645408 PMCID: PMC9889087 DOI: 10.7554/elife.82555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 01/15/2023] [Indexed: 01/17/2023] Open
Abstract
Infantile neuroaxonal dystrophy (INAD) is caused by recessive variants in PLA2G6 and is a lethal pediatric neurodegenerative disorder. Loss of the Drosophila homolog of PLA2G6, leads to ceramide accumulation, lysosome expansion, and mitochondrial defects. Here, we report that retromer function, ceramide metabolism, the endolysosomal pathway, and mitochondrial morphology are affected in INAD patient-derived neurons. We show that in INAD mouse models, the same features are affected in Purkinje cells, arguing that the neuropathological mechanisms are evolutionary conserved and that these features can be used as biomarkers. We tested 20 drugs that target these pathways and found that Ambroxol, Desipramine, Azoramide, and Genistein alleviate neurodegenerative phenotypes in INAD flies and INAD patient-derived neural progenitor cells. We also develop an AAV-based gene therapy approach that delays neurodegeneration and prolongs lifespan in an INAD mouse model.
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Affiliation(s)
- Guang Lin
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Burak Tepe
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Geoff McGrane
- New York Stem Cell Foundation Research InstituteNew YorkUnited States
| | - Regine C Tipon
- New York Stem Cell Foundation Research InstituteNew YorkUnited States
| | - Gist Croft
- New York Stem Cell Foundation Research InstituteNew YorkUnited States
| | | | | | - Agnes JH Liang
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Zhongyuan Zuo
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Seul Kee Byeon
- Department of Laboratory Medicine and Pathology, Mayo ClinicRochesterUnited States
| | - Lily Wang
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
| | - Akhilesh Pandey
- Department of Laboratory Medicine and Pathology, Mayo ClinicRochesterUnited States
- Manipal Academy of Higher Education, ManipalKarnatakaIndia
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of MedicineHoustonUnited States
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s HospitalHoustonUnited States
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
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3
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Bhardwaj NK, Gowda VK, Saini J, Sardesai AV, Santhoshkumar R, Mahadevan A. Neurodegeneration with brain iron accumulation: Characterization of clinical, radiological, and genetic features of pediatric patients from Southern India. Brain Dev 2021; 43:1013-1022. [PMID: 34272103 DOI: 10.1016/j.braindev.2021.06.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/03/2021] [Accepted: 06/28/2021] [Indexed: 12/29/2022]
Abstract
BACKGROUND Neurodegeneration with brain iron accumulation (NBIA) is a group of rare inherited neurodegenerative disorders. Ten types of NBIA are known. Studies reporting various NBIA subtypes together are few. This study was aimed at describing clinical features, neuroimaging findings, and genetic mutations of different NBIA group disorders. METHODS Clinical, radiological, and genetic data of patients diagnosed with NBIA in a tertiary care centre in Southern India from 2014 to 2020 was retrospectively collected and analysed. RESULTS In our cohort of 27 cases, PLA2G6-associated neurodegeneration (PLAN) was most common (n = 13) followed by Pantothenate kinase-associated neurodegeneration (PKAN) (n = 9). We had 2 cases each of Mitochondrial membrane-associated neurodegeneration (MPAN) and Beta-propeller protein- associated neurodegeneration (BPAN) and 1 case of Kufor-Rakeb Syndrome (KRS). Walking difficulty was the presenting complaint in all PKAN cases, whereas the presentation in PLAN was that of development regression with onset at a mean age of 2 years. Overall, 50% patients of them presented with development regression and one-third had epilepsy. Presence of pyramidal signs was most common examination feature (89%) followed by one or more eye findings (81%) and movement disorders (50%). Neuroimaging was abnormal in 24/27 cases and cerebellar atrophy was the commonest finding (52%) followed by globus pallidus hypointensities (44%). CONCLUSIONS One should have a high index of clinical suspicion for the diagnosis of NBIA in children presenting with neuroregression and vision abnormalities in presence of pyramidal signs or movement disorders. Neuroimaging and ophthalmological evaluation provide important clues to diagnosis in NBIA syndromes.
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Affiliation(s)
- Naveen Kumar Bhardwaj
- Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - Vykuntaraju K Gowda
- Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India.
| | - Jitendra Saini
- Neuroradiology, National Institute of Mental Health and Neurosciences, Bangalore, Karnataka, India
| | - Ashwin Vivek Sardesai
- Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - Rashmi Santhoshkumar
- Electron Microscope Laboratory, National Institute of Mental Health and Neurosciences, Bangalore, India
| | - Anita Mahadevan
- Department of Neuropathology, National Institute of Mental Health and Neurosciences, Bangalore, India
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Adams D, Midei M, Dastgir J, Flora C, Molinari RJ, Heerinckx F, Endemann S, Atwal P, Milner P, Shchepinov MS. Treatment of infantile neuroaxonal dystrophy with RT001: A di-deuterated ethyl ester of linoleic acid: Report of two cases. JIMD Rep 2020; 54:54-60. [PMID: 32685351 PMCID: PMC7358664 DOI: 10.1002/jmd2.12116] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 03/04/2020] [Accepted: 03/06/2020] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Infantile neuroaxonal dystrophy (INAD) is a rare, autosomal recessive disease due to defects in PLA2G6 and is associated with lipid peroxidation. RT001 is a di-deuterated form of linoleic acid that protects lipids from oxidative damage. METHODS We evaluated the pharmacokinetics (PK), safety, and effectiveness of RT001 in two subjects with INAD (subject 1: 34 months; subject 2: 10 months). After screening and baseline evaluations, subjects received 1.8 g of RT001 BD. PK analysis and clinical evaluations were made periodically. MAIN FINDINGS Plasma levels of deuterated linoleic acid (D2-LA), deuterated arachidonic acid (D2-AA), D2-LA to total LA, and D2-AA to total AA ratios were measured. The targeted plasma D2-LA ratio (>20%) was achieved by month 1 and maintained throughout the study. RBC AA-ratios were 0.11 and 0.18 at 6 months for subjects 1 and 2; respectively. No treatment-related adverse events occurred. Limited slowing of disease progression and some return of lost developmental milestones were seen. CONCLUSIONS Oral RT001 was administered safely in two subjects with INAD. Early findings suggest that the compound was well tolerated, metabolized and incorporated in the RBC membrane. A clinical trial is underway to assess efficacy.
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Affiliation(s)
- Darius Adams
- Atlantic Health SystemGoryeb Children's HospitalMorristownNew JerseyUSA
| | - Mark Midei
- Clinical DivisionRetrotope, Inc.Los AltosCaliforniaUSA
| | - Jahannaz Dastgir
- Atlantic Health SystemGoryeb Children's HospitalMorristownNew JerseyUSA
| | - Christina Flora
- Atlantic Health SystemGoryeb Children's HospitalMorristownNew JerseyUSA
| | | | | | | | - Paldeep Atwal
- Clinical DivisionRetrotope, Inc.Los AltosCaliforniaUSA
| | - Peter Milner
- Clinical DivisionRetrotope, Inc.Los AltosCaliforniaUSA
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Altuame FD, Foskett G, Atwal PS, Endemann S, Midei M, Milner P, Salih MA, Hamad M, Al-Muhaizea M, Hashem M, Alkuraya FS. The natural history of infantile neuroaxonal dystrophy. Orphanet J Rare Dis 2020; 15:109. [PMID: 32357911 PMCID: PMC7193406 DOI: 10.1186/s13023-020-01355-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 12/25/2019] [Accepted: 03/17/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Infantile neuroaxonal dystrophy (INAD) is a rapidly progressive neurodegenerative disorder of early onset causing premature death. It results from biallelic pathogenic variants in PLA2G6, which encodes a calcium-independent phospholipase A2. OBJECTIVE We aim to outline the natural history of INAD and provide a comprehensive description of its clinical, radiological, laboratory, and molecular findings. MATERIALS AND METHODS We comprehensively analyzed the charts of 28 patients: 16 patients from Riyadh, Saudi Arabia, 8 patients from North and South America and 4 patients from Europe with a molecularly confirmed diagnosis of PLA2G6-associated neurodegeneration (PLAN) and a clinical history consistent with INAD. RESULTS In our cohort, speech impairment and loss of gross motor milestones were the earliest signs of the disease. As the disease progressed, loss of fine motor milestones and bulbar dysfunction were observed. Temporo-frontal function was among the last of the milestones to be lost. Appendicular spastic hypertonia, axial hypotonia, and hyperreflexia were common neurological findings. Other common clinical findings include nystagmus (60.7%), seizures (42.9%), gastrointestinal disease (42.9%), skeletal deformities (35.7%), and strabismus (28.6%). Cerebellar atrophy and elevations in serum AST and LDH levels were consistent features of INAD. There was a statistically significant difference when comparing patients with non-sense/truncating variants compared with missense/in-frame deletions in the time of initial concern (p = 0.04), initial loss of language (p = 0.001), initial loss of fine motor skills (p = 0.009), and initial loss of bulbar skills (p = 0.007). CONCLUSION INAD is an ultra-rare neurodegenerative disorder that presents in early childhood, with a relentlessly progressive clinical course. Knowledge of the natural history of INAD may serve as a resource for healthcare providers to develop a targeted care plan and may facilitate the design of clinical trials to treat this disease.
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Affiliation(s)
- Fadie D Altuame
- College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | | | | | | | | | | | - Mustafa A Salih
- Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Muddathir Hamad
- Division of Pediatric Neurology, Department of Pediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mohammad Al-Muhaizea
- Department of Neurosciences, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Mais Hashem
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
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6
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Guo YP, Tang BS, Guo JF. PLA2G6-Associated Neurodegeneration (PLAN): Review of Clinical Phenotypes and Genotypes. Front Neurol 2018; 9:1100. [PMID: 30619057 PMCID: PMC6305538 DOI: 10.3389/fneur.2018.01100] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [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: 08/24/2018] [Accepted: 12/03/2018] [Indexed: 12/18/2022] Open
Abstract
Phospholipase A2 group VI (PLA2G6)-associated neurodegeneration (PLAN) includes a series of neurodegenerative diseases that result from the mutations in PLA2G6. PLAN has genetic and clinical heterogeneity, with different mutation sites, mutation types and ethnicities and its clinical phenotype is different. The clinical phenotypes and genotypes of PLAN are closely intertwined and vary widely. PLA2G6 encodes a group of VIA calcium-independent phospholipase A2 proteins (iPLA2β), an enzyme involved in lipid metabolism. According to the age of onset and progressive clinical features, PLAN can be classified into the following subtypes: infantile neuroaxonal dystrophy (INAD), atypical neuroaxonal dystrophy (ANAD) and parkinsonian syndrome which contains adult onset dystonia parkinsonism (DP) and autosomal recessive early-onset parkinsonism (AREP). In this review, we present an overview of PLA2G6-associated neurodegeneration in the context of current research.
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Affiliation(s)
- Yu-Pei Guo
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing, China.,Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Bei-Sha Tang
- Center for Brain Disorders Research, Capital Medical University and Beijing Institute of Brain Disorders, Beijing, China.,Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Center for Medical Genetics, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
| | - Ji-Feng Guo
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China.,National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China.,Center for Medical Genetics, Central South University, Changsha, China.,Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
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7
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Mazzotta GM, Bellanda M, Minervini G, Damulewicz M, Cusumano P, Aufiero S, Stefani M, Zambelli B, Mammi S, Costa R, Tosatto SCE. Calmodulin Enhances Cryptochrome Binding to INAD in Drosophila Photoreceptors. Front Mol Neurosci 2018; 11:280. [PMID: 30177872 PMCID: PMC6109769 DOI: 10.3389/fnmol.2018.00280] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 11/14/2017] [Accepted: 07/24/2018] [Indexed: 12/13/2022] Open
Abstract
Light is the main environmental stimulus that synchronizes the endogenous timekeeping systems in most terrestrial organisms. Drosophila cryptochrome (dCRY) is a light-responsive flavoprotein that detects changes in light intensity and wavelength around dawn and dusk. We have previously shown that dCRY acts through Inactivation No Afterpotential D (INAD) in a light-dependent manner on the Signalplex, a multiprotein complex that includes visual-signaling molecules, suggesting a role for dCRY in fly vision. Here, we predict and demonstrate a novel Ca2+-dependent interaction between dCRY and calmodulin (CaM). Through yeast two hybrid, coimmunoprecipitation (Co-IP), nuclear magnetic resonance (NMR) and calorimetric analyses we were able to identify and characterize a CaM binding motif in the dCRY C-terminus. Similarly, we also detailed the CaM binding site of the scaffold protein INAD and demonstrated that CaM bridges dCRY and INAD to form a ternary complex in vivo. Our results suggest a process whereby a rapid dCRY light response stimulates an interaction with INAD, which can be further consolidated by a novel mechanism regulated by CaM.
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Affiliation(s)
| | - Massimo Bellanda
- Department of Chemical Sciences, University of Padova, Padova, Italy
| | | | - Milena Damulewicz
- Department of Cell Biology and Imaging, Institute of Zoology and Biomedical Research, Faculty of Biology and Earth Sciences, Jagiellonian University, Kraków, Poland
| | - Paola Cusumano
- Department of Biology, University of Padova, Padova, Italy
| | - Simona Aufiero
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Monica Stefani
- Department of Chemical Sciences, University of Padova, Padova, Italy
| | - Barbara Zambelli
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Stefano Mammi
- Department of Chemical Sciences, University of Padova, Padova, Italy
| | - Rodolfo Costa
- Department of Biology, University of Padova, Padova, Italy
| | - Silvio C E Tosatto
- Department of Biomedical Sciences, University of Padova, Padova, Italy.,CNR Institute of Neuroscience, Padova, Italy
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8
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Abstract
Neurodegeneration with brain iron accumulation (NBIA) comprises a clinically and genetically heterogeneous group of disorders affecting children and adults. These rare disorders are often first suspected when increased basal ganglia iron is observed on brain magnetic resonance imaging. For the majority of NBIA disorders the genetic basis has been delineated, and clinical testing is available. The four most common NBIA disorders include pantothenate kinase-associated neurodegeneration (PKAN) due to mutations in PANK2, phospholipase A2-associated neurodegeneration caused by mutation in PLA2G6, mitochondrial membrane protein-associated neurodegeneration from mutations in C19orf12, and beta-propeller protein-associated neurodegeneration due to mutations in WDR45. The ultrarare NBIA disorders are caused by mutations in CoASY, ATP13A2, and FA2H (causing CoA synthase protein-associated neurodegeneration, Kufor-Rakeb disease, and fatty acid hydroxylase-associated neurodegeneration, respectively). Together, these genes account for disease in approximately 85% of patients diagnosed with an NBIA disorder. New NBIA genes are being recognized with increasing frequency as a result of whole-exome sequencing, which is also facilitating early ascertainment of patients whose phenotype is often nonspecific.
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Affiliation(s)
- Susan J Hayflick
- Departments of Molecular and Medical Genetics, Pediatrics and Neurology, Oregon Health and Science University, Portland, OR, United States.
| | - Manju A Kurian
- Molecular Neurosciences, Developmental Neurosciences Programme, Institute of Child Health, University College London and Department of Neurology, Great Ormond Street Hospital, London, United Kingdom
| | - Penelope Hogarth
- Departments of Molecular and Medical Genetics and Neurology, Oregon Health and Science University, Portland, OR, United States
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9
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Illingworth MA, Meyer E, Chong WK, Manzur AY, Carr LJ, Younis R, Hardy C, McDonald F, Childs AM, Stewart B, Warren D, Kneen R, King MD, Hayflick SJ, Kurian MA. PLA2G6-associated neurodegeneration (PLAN): further expansion of the clinical, radiological and mutation spectrum associated with infantile and atypical childhood-onset disease. Mol Genet Metab 2014; 112:183-9. [PMID: 24745848 PMCID: PMC4048546 DOI: 10.1016/j.ymgme.2014.03.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 03/21/2014] [Indexed: 11/18/2022]
Abstract
Phospholipase A2 associated neurodegeneration (PLAN) is a major phenotype of autosomal recessive Neurodegeneration with Brain Iron Accumulation (NBIA). We describe the clinical phenotypes, neuroimaging features and PLA2G6 mutations in 5 children, of whom 4 presented with infantile neuroaxonal dystrophy (INAD). One other patient was diagnosed with the onset of PLAN in childhood, and our report highlights the diagnostic challenges associated with this atypical PLAN subtype. In this series, the neuroradiological relevance of classical PLAN features as well as apparent claval hypertrophy' is explored. Novel PLA2G6 mutations were identified in all patients. PLAN should be considered not only in patients presenting with a classic INAD phenotype but also in older patients presenting later in childhood with non-specific progressive neurological features including social communication difficulties, gait disturbance, dyspraxia, neuropsychiatric symptoms and extrapyramidal motor features.
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Affiliation(s)
- M A Illingworth
- Department of Neurology, Great Ormond Street Hospital, London, UK
| | - E Meyer
- Neurosciences Unit, UCL-Institute of Child Health, London, UK
| | - W K Chong
- Department of Radiology, Great Ormond Street Hospital, London, UK
| | - A Y Manzur
- Dubowitz Neuromuscular Centre for Congenital Muscular Dystrophies and Myopathies, Great Ormond Street Hospital, London, UK
| | - L J Carr
- Department of Neurology, Great Ormond Street Hospital, London, UK
| | - R Younis
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - C Hardy
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - F McDonald
- West Midlands Regional Genetics, Birmingham Women's Hospital, Birmingham, UK
| | - A M Childs
- Department of Paediatric Neurology, Leeds General Infirmary, Leeds, UK
| | - B Stewart
- Department of Paediatrics, York Teaching Hospitals NHS Foundation Trust, York, UK
| | - D Warren
- Department of Neuroradiology, Leeds teaching Hospitals, Leeds. UK
| | - R Kneen
- Department of Neurology, Alder Hey Children's Hospital, Liverpool, UK
| | - M D King
- Department of Paediatric Neurology, Children's University Hospital, Temple Street, Dublin, Ireland
| | - S J Hayflick
- Department of Molecular & Medical Genetics, OR Health & Science University, Portland 97239, USA; Department of Paediatrics, OR Health & Science University, Portland 97239, USA; Department of Neurology, OR Health & Science University, Portland 97239, USA
| | - M A Kurian
- Department of Neurology, Great Ormond Street Hospital, London, UK; Neurosciences Unit, UCL-Institute of Child Health, London, UK.
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