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Kaya Özçora GD, Miyatake S, Matsumoto N, Canpolat M, Erdoğan M, Bayramov R, Kumandaş S. PEX10-related autosomal recessive cerebellar ataxia with hearing loss. Acta Neurol Belg 2020; 120:429-432. [PMID: 30022445 DOI: 10.1007/s13760-018-0987-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Accepted: 07/11/2018] [Indexed: 11/26/2022]
Affiliation(s)
- Gül Demet Kaya Özçora
- Department of Pediatric Neurology, Faculty of Medicine, Erciyes University, Kayseri, Turkey.
| | - Satoko Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, 236-0004, Japan
- Clinical Genetics Department, Yokohama City University Hospital, Yokohama, Kanagawa, 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, 236-0004, Japan
| | - Mehmet Canpolat
- Department of Pediatric Neurology, Faculty of Medicine, Erciyes University, Kayseri, Turkey
| | - Murat Erdoğan
- Department of Medical Genetics, Kayseri Training and Research Hospital, Kayseri, Turkey
| | - Ruslan Bayramov
- Medical Genetics Department, Faculty of Medicine, Erciyes University, Kayseri, Turkey
| | - Sefer Kumandaş
- Department of Pediatric Neurology, Faculty of Medicine, Erciyes University, Kayseri, Turkey
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2
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Havali C, Dorum S, Akbaş Y, Görükmez O, Hirfanoglu T. Two different missense mutations of PEX genes in two similar patients with severe Zellweger syndrome: an argument on the genotype-phenotype correlation. J Pediatr Endocrinol Metab 2020; 33:437-441. [PMID: 32069232 DOI: 10.1515/jpem-2019-0194] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 12/16/2019] [Indexed: 11/15/2022]
Abstract
Background Peroxisomal biogenesis disorders (PBDs) include a miscellaneous group of diseases which cause serious multisystem disease. Mutations of 13 different PEX genes lead to PBDs including Zellweger syndrome (ZS). Different types of mutations of PEX1 and PEX10 genes are correlated with broad-range phenotypes of PBDs. Case presentation Patient 1 is a 4-month-old boy who was affected by myoclonic seizures, poor oral feeding since birth. The patient was hypotonic and had hepatosplenomegaly. Patient 2 is a 2-month-old boy who presented with decreased movement, severe hypotonia and failure to thrive. The laboratory studies of the patients revealed increased plasma very-long-chain fatty acids (VLCFAs). The genetic analyses of patient 1 demonstrated the first homozygous missense mutation in the PEX10 gene. A novel homozygous missense mutation was found in the PEX1 gene in patient 2. Conclusions This report highlights that the detected homozygous missense mutations of PEX10 and PEX1 genes and the substitutions of specific amino acids lead to the severe form of PBDs.
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Affiliation(s)
- Cengiz Havali
- Bursa Yuksek İhtisas Training and Research Hospital, Department of Pediatrics, Division of Neurology, Yıldırım/Bursa 16310, Turkey
- Department of Pediatrics, Division of Neurology, Bursa Yuksek İhtisas Training and Research Hospital, Bursa, Turkey
| | - Sevil Dorum
- Department of Pediatrics, Division of Pediatric Metabolic Disorders, Bursa Yuksek İhtisas Training and Research Hospital, Bursa, Turkey
| | - Yılmaz Akbaş
- Department of Pediatric Neurology, Gazi University Faculty of Medicine, Ankara, Turkey
| | - Orhan Görükmez
- Department of Medical Genetics, Bursa Yuksek İhtisas Training and Research Hospital, Bursa, Turkey
| | - Tugba Hirfanoglu
- Department of Pediatric Neurology, Gazi University Faculty of Medicine, Ankara, Turkey
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3
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Zhang C, Zhan FX, Tian WT, Xu YQ, Zhu ZY, Wang Y, Song XW, Cao L. Ataxia with novel compound heterozygous PEX10 mutations and a literature review of PEX10-related peroxisome biogenesis disorders. Clin Neurol Neurosurg 2019; 177:92-96. [PMID: 30640048 DOI: 10.1016/j.clineuro.2019.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 01/03/2019] [Accepted: 01/05/2019] [Indexed: 10/27/2022]
Abstract
OBJECTIVES To describe the clinical and genetic features of a Chinese peroxisome biogenesis disorder 6B patient with PEX10 mutations and review PEX10-related peroxisomal disorders. PATIENTS AND METHODS The proband is a 7-year-old boy with mild mental retardation and gait instability, intention tremor and nystagmus. An extensive clinical and laboratory evaluation including molecular genetic studies was performed. Genomic DNA was extracted from peripheral blood using the standardized phenol/chloroform extraction method, and the coding region of the PEX10 gene was sequenced in three family members. RESULTS Cerebral MRI showed cerebellar atrophy. Magnetic resonance spectroscopy revealed a decreased N-acetyl aspartate peak in the cerebellum. Nerve conduction velocity examination found prolonged motor and sensory nerve potential latencies (proximal obvious), decreased potential amplitude, and slow nerve conduction velocity. Routine blood tests and biochemistries were abnormal. The PEX10 gene test showed compound heterozygous mutations (c.209 G > A, p. G70E and c.830 T > C, p. L277 P). The mutation c.830 T > C, p. L277 P has been previously reported, whereas c.209 G > A, p. G70E is novel. CONCLUSION We identified an ataxia case of peroxisome biogenesis disorder 6B caused by novel compound heterozygous mutations of the PEX10 gene. Peroxisome biogenesis disorders should be considered in the differential diagnosis of autosomal recessive ataxia, especially cases with early onset.
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Affiliation(s)
- Chao Zhang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China; School of Medicine, Anhui University of Science and Technology, Anhui 232001, China
| | - Fei-Xia Zhan
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China
| | - Wo-Tu Tian
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China
| | - Yang-Qi Xu
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China
| | - Ze-Yu Zhu
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China
| | - Yan Wang
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China
| | - Xing-Wang Song
- Department of the Second Affiliated Hospital and Institute of Neuroscience of Guangzhou, Medical University, Guangzhou 510260, China.
| | - Li Cao
- Department of Neurology and Institute of Neurology, Rui Jin Hospital & Rui Jin Hospital North, Shanghai Jiao Tong University School of Medicine, 200025, China.
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4
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Blomqvist M, Ahlberg K, Lindgren J, Ferdinandusse S, Asin-Cayuela J. Identification of a novel mutation in PEX10 in a patient with attenuated Zellweger spectrum disorder: a case report. J Med Case Rep 2017; 11:218. [PMID: 28784167 PMCID: PMC5547663 DOI: 10.1186/s13256-017-1365-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 06/23/2017] [Indexed: 12/05/2022] Open
Abstract
Background The peroxisome biogenesis disorders, which are caused by mutations in any of 13 different PEX genes, include the Zellweger spectrum disorders. Severe defects in one of these PEX genes result in the absence of functional peroxisomes which is seen in classical Zellweger syndrome. These patients present with hypotonia and seizures shortly after birth. Other typical symptoms are dysmorphic features, liver disease, retinal degeneration, sensorineural deafness, polycystic kidneys, and the patient does not reach any developmental milestones. Case presentation We report a case of a patient with Zellweger spectrum disorder due to a novel mutation in the PEX10 gene, presenting with a mild late-onset neurological phenotype. The patient, an Assyrian girl originating from Iraq, presented with sensorineural hearing impairment at the age of 5 followed by sensorimotor polyneuropathy, cognitive delay, impaired gross and fine motor skills, and tremor and muscle weakness in her teens. Analyses of biochemical markers for peroxisomal disease suggested a mild peroxisomal defect and functional studies in fibroblasts confirmed the existence of a peroxisome biogenesis disorder. Diagnosis was confirmed by next generation sequencing analysis, which showed a novel homozygous mutation (c.530 T > G (p.Leu177Arg) (NM_153818.1)) in the PEX10 gene predicted to be pathogenic. Conclusions This case highlights the importance of performing biochemical, functional, and genetic peroxisomal screening in patients with clinical presentations milder than those usually observed in Zellweger spectrum disorders.
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Affiliation(s)
- Maria Blomqvist
- Institute of Biomedicine, Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden.
| | - Karin Ahlberg
- Paediatric Clinic, Central Hospital, S-65185, Karlstad, Sweden
| | - Julia Lindgren
- Institute of Biomedicine, Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Department of Clinical Chemistry, Academic Medical Center, Amsterdam, The Netherlands
| | - Jorge Asin-Cayuela
- Institute of Biomedicine, Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
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5
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Yamashita T, Mitsui J, Shimozawa N, Takashima S, Umemura H, Sato K, Takemoto M, Hishikawa N, Ohta Y, Matsukawa T, Ishiura H, Yoshimura J, Doi K, Morishita S, Tsuji S, Abe K. Ataxic form of autosomal recessive PEX10-related peroxisome biogenesis disorders with a novel compound heterozygous gene mutation and characteristic clinical phenotype. J Neurol Sci 2017; 375:424-429. [PMID: 28320181 DOI: 10.1016/j.jns.2017.02.058] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 11/30/2022]
Abstract
Peroxisome biogenesis factor 10 (PEX10) is involved in the import of peroxisomal matrix proteins, and the mutation of this gene causes 3 subtypes of peroxisome biogenesis disorders, namely Zellweger syndrome (severe), neonatal adrenoleukodystrophy (moderate) and an ataxic form (mild). Here, we report 3 siblings of the ataxic form with cerebellar ataxia, mild mental retardation, and 3 additional characteristic features: mydriasis, hyperreflexia and involuntary head movement. All 3 siblings are compound heterozygous for a previously reported mutation, c.2T>C (p.M1T), and a novel mutation, c.920G>A, causing a missense change (p.C307Y) located in the RING finger domain of PEX10. The present cases suggest that these PEX10 mutations involve not only cerebellar but also more multiple nervous systems including pupillary autonomic, pyramidal and extrapyramidal systems.
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Affiliation(s)
- Toru Yamashita
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Jun Mitsui
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan
| | - Nobuyuki Shimozawa
- Division of Genomic Research, Life Science Research Center, Gifu University, Gifu 501-1193, Japan
| | - Shigeo Takashima
- Division of Genomic Research, Life Science Research Center, Gifu University, Gifu 501-1193, Japan
| | - Hiroshi Umemura
- Department of Dermatology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Kota Sato
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Mami Takemoto
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Nozomi Hishikawa
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Yasuyuki Ohta
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan
| | - Takashi Matsukawa
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan
| | - Hiroyuki Ishiura
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan
| | - Jun Yoshimura
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 113-8655, Japan
| | - Koichiro Doi
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 113-8655, Japan
| | - Shinichi Morishita
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo 113-8655, Japan
| | - Shoji Tsuji
- Department of Neurology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8655, Japan
| | - Koji Abe
- Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikatacho, Okayama 700-8558, Japan..
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6
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Renaud M, Guissart C, Mallaret M, Ferdinandusse S, Cheillan D, Drouot N, Muller J, Claustres M, Tranchant C, Anheim M, Koenig M. Expanding the spectrum of PEX10-related peroxisomal biogenesis disorders: slowly progressive recessive ataxia. J Neurol 2016; 263:1552-8. [PMID: 27230853 DOI: 10.1007/s00415-016-8167-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/09/2016] [Accepted: 05/09/2016] [Indexed: 11/24/2022]
Abstract
Peroxisomal biogenesis disorders (PBDs) consist of a heterogeneous group of autosomal recessive diseases, in which peroxisome assembly and proliferation are impaired leading to severe multisystem disease and early death. PBDs include Zellweger spectrum disorders (ZSDs) with a relatively mild clinical phenotype caused by PEX1, (MIM# 602136), PEX2 (MIM# 170993), PEX6 (MIM# 601498), PEX10 (MIM# 602859), PEX12 (MIM# 601758), and PEX16 (MIM# 603360) mutations. Three adult patients are reported belonging to a non-consanguineous French family affected with slowly progressive cerebellar ataxia, axonal neuropathy, and pyramidal signs. Mental retardation and diabetes mellitus were optional. The age at onset was in childhood or in adolescence (3-15 years). Brain MRI showed marked cerebellar atrophy. Biochemical blood analyses suggested a mild peroxisomal defect. With whole exome sequencing, two mutations in PEX10 were found in the three patients: c.827G>T (novel) causing the missense change p.Cys276Phe and c.932G>A causing the missense change p.Arg311Gln. The phenotypic spectrum related to PEX10 mutations includes slowly progressive, syndromic recessive ataxia.
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Affiliation(s)
- Mathilde Renaud
- Département de Neurologie, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 67098, Strasbourg Cedex, France.,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Claire Guissart
- Laboratoire de Génétique de Maladies Rares, Institut Universitaire de Recherche Clinique, EA7402, Université de Montpellier, CHU Montpellier, 641 Avenue du Doyen Gaston Giraud, 34093, Montpellier Cedex 5, France
| | - Martial Mallaret
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France.,Service de Neurologie, Centre Hospitalier de Haguenau, 67500, Haguenau, France
| | - Sacha Ferdinandusse
- Laboratory Genetic Metabolic Diseases, Academic Medical Center, 1105 AZ, Amsterdam, The Netherlands
| | - David Cheillan
- Hospices Civils de Lyon: Service des Maladies Héréditaires du Métabolisme et Dépistage Néonatal, INSERM U.1060: Laboratoire de Recherche en Cardiovasculaire, Métabolisme, Diabétologie et Nutrition, Lyon, France
| | - Nathalie Drouot
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France
| | - Jean Muller
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France.,Laboratoire de Génétique Médicale, UMR_S INSERM U1112, IGMA, Faculté de Médecine FMTS, Université de Strasbourg, Strasbourg, France.,Laboratoire de Diagnostic Génétique, Hôpitaux Universitaires de Strasbourg, Strasbourg, France
| | - Mireille Claustres
- Laboratoire de Génétique de Maladies Rares, Institut Universitaire de Recherche Clinique, EA7402, Université de Montpellier, CHU Montpellier, 641 Avenue du Doyen Gaston Giraud, 34093, Montpellier Cedex 5, France
| | - Christine Tranchant
- Département de Neurologie, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 67098, Strasbourg Cedex, France.,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Mathieu Anheim
- Département de Neurologie, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 67098, Strasbourg Cedex, France.,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404, Illkirch, France.,Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Michel Koenig
- Laboratoire de Génétique de Maladies Rares, Institut Universitaire de Recherche Clinique, EA7402, Université de Montpellier, CHU Montpellier, 641 Avenue du Doyen Gaston Giraud, 34093, Montpellier Cedex 5, France.
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7
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Peripheral nervous system defects in a mouse model for peroxisomal biogenesis disorders. Dev Biol 2014; 395:84-95. [PMID: 25176044 DOI: 10.1016/j.ydbio.2014.08.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 08/19/2014] [Accepted: 08/20/2014] [Indexed: 12/19/2022]
Abstract
Peroxisome biogenesis disorders (PBD) are autosomal recessive disorders in humans characterized by skeletal, eye and brain abnormalities. Despite the fact that neurological deficits, including peripheral nervous system (PNS) defects, can be observed at birth in some PBD patients including those with PEX10 mutations, the embryological basis of the PNS defects is unclear. Using a forward genetic screen, we identified a mouse model for Pex10 deficiency that exhibits neurological abnormalities during fetal development. Homozygous Pex10 mutant mouse embryos display biochemical abnormalities related to a PBD deficiency. During late embryogenesis, Pex10 homozygous mutant mice experience progressive loss of movement and at birth they become cyanotic and die shortly thereafter. Homozygous Pex10 mutant fetuses display decreased integrity of axons and synapses, over-extension of axons in the diaphragm and decreased Schwann cell numbers. Our neuropathological, molecular and electrophysiological studies provide new insights into the embryological basis of the PNS deficits in a PBD model. Our findings identify PEX10 function, and likely other PEX proteins, as an essential component of the spinal locomotor circuit.
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8
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Shiba N, Daza RAM, Shaffer LG, Barkovich AJ, Dobyns WB, Hevner RF. Neuropathology of brain and spinal malformations in a case of monosomy 1p36. Acta Neuropathol Commun 2013; 1:45. [PMID: 24252393 PMCID: PMC3893467 DOI: 10.1186/2051-5960-1-45] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 07/18/2013] [Indexed: 11/10/2022] Open
Abstract
Monosomy 1p36 is the most common subtelomeric chromosomal deletion linked to mental retardation and seizures. Neuroimaging studies suggest that monosomy 1p36 is associated with brain malformations including polymicrogyria and nodular heterotopia, but the histopathology of these lesions is unknown. Here we present postmortem neuropathological findings from a 10 year-old girl with monosomy 1p36, who died of respiratory complications. The findings included micrencephaly, periventricular nodular heterotopia in occipitotemporal lobes, cortical dysgenesis resembling polymicrogyria in dorsolateral frontal lobes, hippocampal malrotation, callosal hypoplasia, superiorly rotated cerebellum with small vermis, and lumbosacral hydromyelia. The abnormal cortex exhibited “festooned” (undulating) supragranular layers, but no significant fusion of the molecular layer. Deletion mapping demonstrated single copy loss of a contiguous 1p36 terminal region encompassing many important neurodevelopmental genes, among them four HES genes implicated in regulating neural stem cell differentiation, and TP73, a monoallelically expressed gene. Our results suggest that brain and spinal malformations in monosomy 1p36 may be more extensive than previously recognized, and may depend on the parental origin of deleted genes. More broadly, our results suggest that specific genetic disorders may cause distinct forms of cortical dysgenesis.
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9
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El Magraoui F, Bäumer BE, Platta HW, Baumann JS, Girzalsky W, Erdmann R. The RING-type ubiquitin ligases Pex2p, Pex10p and Pex12p form a heteromeric complex that displays enhanced activity in an ubiquitin conjugating enzyme-selective manner. FEBS J 2012; 279:2060-70. [PMID: 22471590 DOI: 10.1111/j.1742-4658.2012.08591.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The RING finger peroxins Pex2p, Pex10p and Pex12p are central components of the peroxisomal matrix protein import machinery. The RING domain enables each of these proteins to exhibit ubiquitin-protein ligase activity, which has been linked to ubiquitin-dependent regulation of the peroxisomal import receptor Pex5p. The RING peroxins are considered to form a heteromeric complex in vivo, although the elucidation of the structural assembly, as well as the functional interplay of the RING domains, has remained elusive. Using in vitro approaches, we show that the RING domains form a heteromeric complex with Pex10p(RING) as a central component that directly binds the Pex2p(RING) and Pex12p(RING). The RING domains proved to function as heteromeric pairs that display an Pex10p-dependent enhanced ligase activity in an ubiquitin conjugating enzyme-selective manner.
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Affiliation(s)
- Fouzi El Magraoui
- Abteilung für Systembiochemie, Institut für Physiologische Chemie, Medizinische Fakultät, Ruhr-Universität Bochum, Germany
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10
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Waterham HR, Ebberink MS. Genetics and molecular basis of human peroxisome biogenesis disorders. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1430-41. [PMID: 22871920 DOI: 10.1016/j.bbadis.2012.04.006] [Citation(s) in RCA: 189] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 03/30/2012] [Accepted: 04/11/2012] [Indexed: 10/28/2022]
Abstract
Human peroxisome biogenesis disorders (PBDs) are a heterogeneous group of autosomal recessive disorders comprised of two clinically distinct subtypes: the Zellweger syndrome spectrum (ZSS) disorders and rhizomelic chondrodysplasia punctata (RCDP) type 1. PBDs are caused by defects in any of at least 14 different PEX genes, which encode proteins involved in peroxisome assembly and proliferation. Thirteen of these genes are associated with ZSS disorders. The genetic heterogeneity among PBDs and the inability to predict from the biochemical and clinical phenotype of a patient with ZSS which of the currently known 13 PEX genes is defective, has fostered the development of different strategies to identify the causative gene defects. These include PEX cDNA transfection complementation assays followed by sequencing of the thus identified PEX genes, and a PEX gene screen in which the most frequently mutated exons of the different PEX genes are analyzed. The benefits of DNA testing for PBDs include carrier testing of relatives, early prenatal testing or preimplantation genetic diagnosis in families with a recurrence risk for ZSS disorders, and insight in genotype-phenotype correlations, which may eventually assist to improve patient management. In this review we describe the current status of genetic analysis and the molecular basis of PBDs.
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11
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Ebberink MS, Mooijer PAW, Gootjes J, Koster J, Wanders RJA, Waterham HR. Genetic classification and mutational spectrum of more than 600 patients with a Zellweger syndrome spectrum disorder. Hum Mutat 2011; 32:59-69. [PMID: 21031596 DOI: 10.1002/humu.21388] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The autosomal recessive Zellweger syndrome spectrum (ZSS) disorders comprise a main subgroup of the peroxisome biogenesis disorders and can be caused by mutations in any of 12 different currently identified PEX genes resulting in severe multisystemic disorders. To get insight into the spectrum of PEX gene defects among ZSS disorders and to investigate if additional human PEX genes are required for functional peroxisome biogenesis, we assigned over 600 ZSS fibroblast cell lines to different genetic complementation groups. These fibroblast cell lines were subjected to a complementation assay involving fusion by means of polyethylene glycol or a PEX cDNA transfection assay specifically developed for this purpose. In a majority of the cell lines we subsequently determined the underlying mutations by sequence analysis of the implicated PEX genes. The PEX cDNA transfection assay allows for the rapid identification of PEX genes defective in ZSS patients. The assignment of over 600 fibroblast cell lines to different genetic complementation groups provides the most comprehensive and representative overview of the frequency distribution of the different PEX gene defects. We did not identify any novel genetic complementation group, suggesting that all PEX gene defects resulting in peroxisome deficiency are currently known.
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Affiliation(s)
- Merel S Ebberink
- Academic Medical Centre at the University of Amsterdam, The Netherlands
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12
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Yik WY, Steinberg SJ, Moser AB, Moser HW, Hacia JG. Identification of novel mutations and sequence variation in the Zellweger syndrome spectrum of peroxisome biogenesis disorders. Hum Mutat 2009; 30:E467-80. [PMID: 19105186 DOI: 10.1002/humu.20932] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Peroxisome biogenesis disorders (PBD) are a heterogeneous group of autosomal recessive neurodegenerative disorders that affect multiple organ systems. Approximately 80% of PBD patients are classified in the Zellweger syndrome spectrum (PBD-ZSS). Mutations in the PEX1, PEX6, PEX10, PEX12, or PEX26 genes are found in approximately 90% of PBD-ZSS patients. Here, we sequenced the coding regions and splice junctions of these five genes in 58 PBD-ZSS cases previously subjected to targeted sequencing of a limited number of PEX gene exons. In our cohort, 71 unique sequence variants were identified, including 18 novel mutations predicted to disrupt protein function and 2 novel silent variants. We identified 4 patients who had two deleterious mutations in one PEX gene and a third deleterious mutation in a second PEX gene. For two such patients, we conducted cell fusion complementation analyses to identify the defective gene responsible for aberrant peroxisome assembly. Overall, we provide empirical data to estimate the relative fraction of disease-causing alleles that occur in the coding and splice junction sequences of these five PEX genes and the frequency of cases where mutations occur in multiple PEX genes. This information is beneficial for efforts aimed at establishing rapid and sensitive clinical diagnostics for PBD-ZSS patients and interpreting the results from these genetic tests.
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Affiliation(s)
- Wing Yan Yik
- Department of Biochemistry and Molecular Biology, University of Southern California, Los Angeles, California, USA
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Steinberg SJ, Snowden A, Braverman NE, Chen L, Watkins PA, Clayton PT, Setchell KDR, Heubi JE, Raymond GV, Moser AB, Moser HW. A PEX10 defect in a patient with no detectable defect in peroxisome assembly or metabolism in cultured fibroblasts. J Inherit Metab Dis 2009; 32:109-19. [PMID: 19127411 DOI: 10.1007/s10545-008-0969-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Revised: 09/10/2008] [Accepted: 10/09/2008] [Indexed: 11/28/2022]
Abstract
Zellweger spectrum disorders (ZSD) are diagnosed by biochemical assay in blood, urine and cultured fibroblasts and PEX gene mutation identification. In most cases studies in fibroblasts corroborate results obtained in body fluids. In 1996 Clayton and colleagues described a 10-year old girl with evidence of a peroxisome disorder, based on elevated bile acid metabolites and phytanate. At the time it was not possible to distinguish whether she had a ZSD or a single peroxisomal protein defect. Studies in our laboratory showed that she also had elevated plasma pipecolate, supporting the former diagnosis. Despite the abnormal metabolites detected in blood (phytanate, bile acid intermediates and pipecolate), analysis of multiple peroxisomal pathways in fibroblasts yielded normal results. In addition, she had a milder clinical phenotype than usually associated with ZSD. Since complementation analysis to determine the gene defect was not possible, we screened this patient following the PEX Gene Screen algorithm (PGS). The PGS provides a template for sequencing PEX gene exons independent of complementation analysis. Two mutations in PEX10 were identified, a frameshift mutation inherited from her father and a de novo missense mutation in a conserved functional domain on the other allele. This case highlights that molecular analysis may be essential to the diagnosis of patients at the milder end of the ZSD spectrum. Furthermore, it supports the concept that some tissues are less affected by certain PEX gene defects than brain and liver.
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Affiliation(s)
- S J Steinberg
- Neurogenetics, Kennedy Krieger Institute, Baltimore, Maryland 21205, USA.
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Turner CLS, Bunyan DJ, Thomas NS, Mackay DJG, Jones HP, Waterham HR, Wanders RJA, Temple IK. Zellweger syndrome resulting from maternal isodisomy of chromosome 1. Am J Med Genet A 2007; 143A:2172-7. [PMID: 17702006 DOI: 10.1002/ajmg.a.31912] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Zellweger syndrome (ZS) is an autosomal recessive peroxisomal disorder that results from mutations in one of the peroxisome biogenesis (PEX) genes. This is the first patient reported with uniparental disomy (UPD) resulting in ZS, in this case maternal isodisomy of chromosome 1 involving reduction to homoallelism of a frameshift mutation within PEX 10. Other reported cases of UPD1, and evidence for the imprinting of genes on chromosome 1, are reviewed. The molecular findings in this patient have important implications for molecular testing and genetic counseling in ZS.
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Affiliation(s)
- Claire L S Turner
- Wessex Clinical Genetics Service, Southampton University Hospital NHS Trust, Princess Anne Hospital, Coxford Road, Southampton, UK.
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Steinberg SJ, Dodt G, Raymond GV, Braverman NE, Moser AB, Moser HW. Peroxisome biogenesis disorders. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1733-48. [PMID: 17055079 DOI: 10.1016/j.bbamcr.2006.09.010] [Citation(s) in RCA: 338] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Revised: 09/05/2006] [Accepted: 09/06/2006] [Indexed: 01/02/2023]
Abstract
Defects in PEX genes impair peroxisome assembly and multiple metabolic pathways confined to this organelle, thus providing the biochemical and molecular bases of the peroxisome biogenesis disorders (PBD). PBD are divided into two types--Zellweger syndrome spectrum (ZSS) and rhizomelic chondrodysplasia punctata (RCDP). Biochemical studies performed in blood and urine are used to screen for the PBD. DNA testing is possible for all of the disorders, but is more challenging for the ZSS since 12 PEX genes are known to be associated with this spectrum of PBD. In contrast, PBD-RCDP is associated with defects in the PEX7 gene alone. Studies of the cellular and molecular defects in PBD patients have contributed significantly to our understanding of the role of each PEX gene in peroxisome assembly.
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Affiliation(s)
- Steven J Steinberg
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Steinberg S, Chen L, Wei L, Moser A, Moser H, Cutting G, Braverman N. The PEX Gene Screen: molecular diagnosis of peroxisome biogenesis disorders in the Zellweger syndrome spectrum. Mol Genet Metab 2004; 83:252-63. [PMID: 15542397 DOI: 10.1016/j.ymgme.2004.08.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Revised: 08/14/2004] [Accepted: 08/20/2004] [Indexed: 10/26/2022]
Abstract
Peroxisome biogenesis disorders in the Zellweger syndrome spectrum (PBD-ZSS) are caused by defects in at least 12 PEX genes required for normal organelle assembly. Clinical and biochemical features continue to be used reliably to assign patients to this general disease category. Identification of the precise genetic defect is important, however, to permit carrier testing and early prenatal diagnosis. Molecular analysis is likely to expand the clinical spectrum of PBD and may also provide data relevant to prognosis and future therapeutic intervention. However, the large number of genes involved has thus far impeded rapid mutation identification. In response, we developed the PEX Gene Screen, an algorithm for the systematic screening of exons in the six PEX genes most commonly defective in PBD-ZSS. We used PCR amplification of genomic DNA and sequencing to screen 91 unclassified PBD-ZSS patients for mutations in PEX1, PEX26, PEX6, PEX12, PEX10, and PEX2. A maximum of 14 reactions per patient identified pathological mutations in 79% and both mutant alleles in 54%. Twenty-five novel mutations were identified overall. The proportion of patients with different PEX gene defects correlated with frequencies previously identified by complementation analysis. This systematic, hierarchical approach to mutation identification is therefore a valuable tool to identify rapidly the molecular etiology of suspected PBD-ZSS disorders.
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Affiliation(s)
- Steven Steinberg
- Peroxisomal Diseases Laboratory, Kennedy Krieger Institute and Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
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Gootjes J, Schmohl F, Waterham HR, Wanders RJA. Novel mutations in the PEX12 gene of patients with a peroxisome biogenesis disorder. Eur J Hum Genet 2004; 12:115-20. [PMID: 14571262 DOI: 10.1038/sj.ejhg.5201090] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The peroxisome biogenesis disorders (PBDs) form a genetically and clinically heterogeneous group of disorders due to defects in at least 11 distinct genes. The prototype of this group of disorders is Zellweger syndrome (ZS), with neonatal adrenoleukodystrophy (NALD) and infantile Refsum disease (IRD) as milder variants. Liver disease, variable neurodevelopmental delay, retinopathy and perceptive deafness are common to PBDs. PBD patients belonging to complementation group 3 (CG3) have mutations in the PEX12 gene, which codes for a protein (PEX12) that contains two transmembrane domains, and a zinc-binding domain considered to be important for its interaction with other proteins of the peroxisomal protein import machinery. We report on the identification of five PBD patients belonging to CG3. Sequence analysis of their PEX12 genes revealed five different mutations, four of which have not been reported before. Four of the patients have mutations that disrupt the translation frame and/or create an early termination codon in the PEX12 open reading frame predicted to result in truncated protein products, lacking at least the COOH-terminal zinc-binding domain. All these patients display the more severe phenotypes (ZS or NALD). The fifth patient expresses two PEX12 alleles capable of encoding a protein that does contain the zinc-binding domain and displayed a milder phenotype (IRD). The three biochemical markers measured in fibroblasts (DHAPAT activity, C26:0 beta-oxidation and pristanic acid beta-oxidation) also correlated with the genotypes. Thus, the genotypes of our CG3 patients show a good correlation with the biochemical and clinical phenotype of the patients.
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Affiliation(s)
- Jeannette Gootjes
- Department of Clinical Chemistry, Academic Medical Center, University of Amsterdam, The Netherlands
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Gootjes J, Elpeleg O, Eyskens F, Mandel H, Mitanchez D, Shimozawa N, Suzuki Y, Waterham HR, Wanders RJA. Novel mutations in the PEX2 gene of four unrelated patients with a peroxisome biogenesis disorder. Pediatr Res 2004; 55:431-6. [PMID: 14630978 DOI: 10.1203/01.pdr.0000106862.83469.8d] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The peroxisome biogenesis disorders (PBDs) form a genetically and clinically heterogeneous group of disorders due to defects in at least 11 distinct genes. The prototype of this group of disorders is Zellweger syndrome (ZS) with neonatal adrenoleukodystrophy (NALD) and infantile Refsum disease (IRD) as milder variants. Common to PBDs are liver disease, variable neurodevelopmental delay, retinopathy and perceptive deafness. PBD patients belonging to complementation group 10 (CG10) have mutations in the PEX2 gene (PXMP3), which codes for a protein (PEX2) that contains two transmembrane domains and a zinc-binding domain considered to be important for its interaction with other proteins of the peroxisomal protein import machinery. We report on the identification of four PBD patients belonging to CG10. Sequence analysis of their PEX2 genes revealed 4 different mutations, 3 of which have not been reported before. Two of the patients had homozygous mutations leading to truncated proteins lacking both transmembrane domains and the zinc-binding domain. These mutations correlated well with their severe phenotypes. The third patient had a homozygous mutation leading to the absence of the zinc-binding domain (W223X) and the fourth patient had a homozygous mutation leading to the change of the second cysteine residue of the zinc-binding domain (C247R). Surprisingly, the patient lacking the domain had a mild phenotype, whereas the C247R patient had a severe phenotype. This might be due to an increased instability of PEX2 due to the R for C substitution or to a dominant negative effect on interacting proteins.
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Affiliation(s)
- Jeannette Gootjes
- Lab. Genetic Metabolic Diseases (F0-224), Department of Clinical Chemistry and Peadiatrics, Emma Children's Hospital, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Abstract
The peroxisome biogenesis disorders (PBDs) comprise 12 autosomal recessive complementation groups (CGs). The multisystem clinical phenotype varies widely in severity and results from disturbances in both development and metabolic homeostasis. Progress over the last several years has lead to identification of the genes responsible for all of these disorders and to a much improved understanding of the biogenesis and function of the peroxisome. Increasing availability of mouse models for these disorders offers hope for a better understanding of their pathophysiology and for development of therapies that might especially benefit patients at the milder end of the clinical phenotype.
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Affiliation(s)
- Sabine Weller
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Schumann U, Wanner G, Veenhuis M, Schmid M, Gietl C. AthPEX10, a nuclear gene essential for peroxisome and storage organelle formation during Arabidopsis embryogenesis. Proc Natl Acad Sci U S A 2003; 100:9626-31. [PMID: 12883010 PMCID: PMC170968 DOI: 10.1073/pnas.1633697100] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In yeasts and mammals, PEX10 encodes an integral membrane protein with a C3HC4 RING finger motif in its C-terminal domain and is required for peroxisome biogenesis and matrix protein import. In humans, its dysfunction in peroxisome biogenesis leads to severe Zellweger Syndrome and infantile Refsum disease. Here we show that dysfunction of a homologous gene in Arabidopsis leads to lethality at the heart stage of embryogenesis, impairing the biogenesis of peroxisomes, lipid bodies, and protein bodies. In a T-DNA insertion mutant disrupting the fourth exon of the AthPEX10 gene, ultrastructural analyses fail to detect peroxisomes characteristic for wild-type embryogenesis. Storage triacyl glycerides are not assembled into lipid bodies (oil bodies; oleosomes) surrounded by the phospholipid-protein monolayer membrane. Instead, the dysfunctional monolayer membranes, which derive from the bilayer membrane of the endoplasmic reticulum, accumulate in the cytosol. Concomitantly the transfer of the storage proteins from their site of synthesis at the endoplasmic reticulum to the vacuoles is disturbed. The mutant can be rescued by transformation with wild-type AthPEX10 cDNA. Transformants of wild-type Hansenula polymorpha cells with the AthPEX10 cDNA did produce the encoded protein without targeting it to peroxisomes. Additionally, the cDNA could not complement a Hansenula pex10 mutant unable to form peroxisomes. The ultrastructural knockout phenotype of AthPEX10p suggests that this protein in Arabidopsis is essential for peroxisome, oleosome, and protein transport vesicle formation.
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Affiliation(s)
- Uwe Schumann
- Lehrstuhl für Botanik, Technische Universität München, Am Hochanger 4, D-85350 Freising, Germany
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Dodt G, Warren D, Becker E, Rehling P, Gould SJ. Domain mapping of human PEX5 reveals functional and structural similarities to Saccharomyces cerevisiae Pex18p and Pex21p. J Biol Chem 2001; 276:41769-81. [PMID: 11546814 DOI: 10.1074/jbc.m106932200] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PEX5 functions as an import receptor for proteins with the type-1 peroxisomal targeting signal (PTS1). Although PEX5 is not involved in the import of PTS2-targeted proteins in yeast, it is essential for PTS2 protein import in mammalian cells. Human cells generate two isoforms of PEX5 through alternative splicing, PEX5S and PEX5L, and PEX5L contains an additional insert 37 amino acids long. Only one isoform, PEX5L, is involved in PTS2 protein import, and PEX5L physically interacts with PEX7, the import receptor for PTS2-containing proteins. In this report we map the regions of human PEX5L involved in PTS2 protein import, PEX7 interaction, and targeting to peroxisomes. These studies revealed that amino acids 1-230 of PEX5L are required for PTS2 protein import, amino acids 191-222 are sufficient for PEX7 interaction, and amino acids 1-214 are sufficient for targeting to peroxisomes. We also identified a 21-amino acid-long peptide motif of PEX5L, amino acids 209-229, that overlaps the regions sufficient for full PTS2 rescue activity and PEX7 interaction and is shared by Saccharomyces cerevisiae Pex18p and Pex21p, two yeast peroxins that act only in PTS2 protein import in yeast. A mutation in PEX5 that changes a conserved serine of this motif abrogates PTS2 protein import in mammalian cells and reduces the interaction of PEX5L and PEX7 in vitro. This peptide motif also lies within regions of Pex18p and Pex21p that interact with yeast PEX7. Based on these and other results, we propose that mammalian PEX5L may have acquired some of the functions that yeast Pex18p and/or Pex21p perform in PTS2 protein import. This hypothesis may explain the essential role of PEX5L in PTS2 protein import in mammalian cells and its lack of importance for PTS2 protein import in yeast.
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Affiliation(s)
- G Dodt
- Institut für Physiologische Chemie, Systembiochemie Ruhr-Universität, 44801 Bochum, Germany.
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