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1.
J Cell Sci ; 135(17)2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35950506

RESUMO

VPS13 family proteins form conduits between the membranes of different organelles through which lipids are transferred. In humans, there are four VPS13 paralogs, and mutations in the genes encoding each of them are associated with different inherited disorders. VPS13 proteins contain multiple conserved domains. The Vps13 adaptor-binding (VAB) domain binds to adaptor proteins that recruit VPS13 to specific membrane contact sites. This work demonstrates the importance of a different domain in VPS13A function. The pleckstrin homology (PH) domain at the C-terminal region of VPS13A is required to form a complex with the XK scramblase and for the co-localization of VPS13A with XK within the cell. Alphafold modeling was used to predict an interaction surface between VPS13A and XK. Mutations in this region disrupt both complex formation and co-localization of the two proteins. Mutant VPS13A alleles found in patients with VPS13A disease truncate the PH domain. The phenotypic similarities between VPS13A disease and McLeod syndrome caused by mutations in VPS13A and XK, respectively, argue that loss of the VPS13A-XK complex is the basis of both diseases.


Assuntos
Neuroacantocitose , Proteínas de Transporte Vesicular , Humanos , Membranas Mitocondriais/metabolismo , Mutação/genética , Neuroacantocitose/complicações , Neuroacantocitose/genética , Neuroacantocitose/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
2.
Mol Genet Genomics ; 299(1): 39, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519717

RESUMO

Chorea-acanthocytosis (ChAc) is a rare autosomal recessive neurodegenerative disorder characterized by a variety of involuntary movements, predominantly chorea, and the presence of acanthocytosis in peripheral blood smears. ChAc is caused by mutations in the vacuolar protein sorting-associated protein 13A (VPS13A) gene. The aim of the present study was to conduct a clinical and genetic analysis of five patients with suspected ChAc in Iran. This study included five patients who were referred to the genetic department of the Endocrinology and Metabolism Research Institute between 2020 and 2022, with a suspicion of ChAc. Clinical features and the presence of characteristic MRI findings were evaluated in the patients. Whole-exome sequencing (WES) followed by Sanger sequencing was employed to identify the disease-causing variants. The functional effects of novel mutations were analyzed by specific bioinformatics prediction tools. WES and data analysis revealed the presence of five distinct VPS13A mutations in the patients, four of which were novel. These included one nonsense mutation (p.L984X), and three splice site mutations (c.755-1G>A, c.144+1 G>C, c.2512+1G>A). All mutations were validated by Sanger sequencing, and in silico analysis predicted that all mutations were pathogenic. This study provides the first molecular genetic characteristics of Iranian patients with ChAc, identifying four novel mutations in the VPS13A gene. These findings expand the VPS13A variants spectrum and confirm the clinical variability in ChAc patients.


Assuntos
Neuroacantocitose , Proteínas de Transporte Vesicular , Humanos , Irã (Geográfico) , Mutação , Neuroacantocitose/genética , Neuroacantocitose/patologia , Transporte Proteico , Proteínas de Transporte Vesicular/genética
3.
Neurol Sci ; 45(5): 2057-2061, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37985634

RESUMO

Chorea-acanthocytosis (ChAc) is a rare clinical genetic disorder of the nervous system, which is characterized by choreiform movement disorder, cognitive decline, and psychiatric disorders. ChAc is mostly diagnosed based on its typical clinical manifestations and the increased number of acanthocytes in peripheral blood smears. Here, we report a patient, who has the characteristic clinical manifestations of ChAc with limb choreiform movements, involuntary lip and tongue bites, seizures, and emotional instability. However, her blood smear was negative for acanthocytes with scanning electron microscopy. We later identified two novel pathogenic mutations in the patient's vacuolar protein sorting homolog 13 A (VPS13A) on chromosome 9q21 by targeted gene sequencing, and she was definitively diagnosed with "ChAc." After treatment with carbamazepine, haloperidol, the patient's symptoms gradually improved. We consider that an acanthocyte negative blood smear cannot rule out ChAC diagnosis, and genetic testing is the "gold standard" for the diagnosis. Through a review of previous research, it is rare for a patient to have a clear diagnosis of ChAc by genetic testing, but whose blood smear is negative for acanthocytes with electron microscopy. In addition, in this report, we discovered two novel pathogenic mutations, which have not been reported previously, and extended the genetic characteristics of ChAc.


Assuntos
Transtornos dos Movimentos , Neuroacantocitose , Humanos , Feminino , Neuroacantocitose/diagnóstico , Neuroacantocitose/genética , Neuroacantocitose/patologia , Acantócitos/metabolismo , Acantócitos/patologia , Transtornos dos Movimentos/patologia , Transporte Proteico , Mutação/genética , Proteínas de Transporte Vesicular/genética
4.
Bioessays ; 44(10): e2200106, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35996795

RESUMO

Extracellular ATP released from necrotic cells in inflamed tissues activates the P2X7 receptor, stimulates the exposure of phosphatidylserine, and causes cell lysis. Recent findings indicated that XK, a paralogue of XKR8 lipid scramblase, forms a complex with VPS13A at the plasma membrane of T cells. Upon engagement by ATP, an unidentified signal(s) from the P2X7 receptor activates the XK-VPS13A complex to scramble phospholipids, followed by necrotic cell death. P2X7 is expressed highly in CD25+ CD4+ T cells but weakly in CD8+ T cells, suggesting a role of this system in the activation of the immune system to prevent infection. On the other hand, a loss-of-function mutation in XK or VPS13A causes neuroacanthocytosis, indicating the crucial involvement of XK-VPS13A-mediated phospholipid scrambling at plasma membranes in the maintenance of homeostasis in the nervous and red blood cell systems.


Assuntos
Fosfatidilserinas , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Morte Celular , Membrana Celular/metabolismo , Fosfatidilserinas/metabolismo , Fosfolipídeos/metabolismo , Receptores Purinérgicos P2X7/genética , Receptores Purinérgicos P2X7/metabolismo
5.
Ecotoxicol Environ Saf ; 286: 117225, 2024 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-39427538

RESUMO

Atrazine (ATR) is a broad-spectrum herbicide with dopaminergic (DAergic) neurotoxicity that can cause Parkinson's disease (PD)-like syndrome. However, research on preventing ATR neurotoxicity is unclear. Soybean isoflavones (SI) are natural plant compounds with neuroprotective effects. In this study, we found that pre-administration of SI prevented ATR-induced motor dysfunction and substantia nigra pathological damage. RNA-seq datasets revealed that the neuroprotective effect of SI was related to autophagy. Further experiments showed that ATR inhibited autophagy, and SI pre-administration before ATR exposure increased autophagy. In addition, single-cell data analysis combined with experimental verification showed that the gene VPS13A was a key target by which SI protected DAergic neurons from ATR damage, and inhibiting VPS13A-induced autophagy was a key mechanism enabling SI prevention of neuron damage. Together, these findings provide new insights for the development of preventive measures and intervention targets protecting against functional neuronal damage caused by ATR and other herbicides.

6.
Int J Mol Sci ; 25(14)2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39063018

RESUMO

The Vps13a gene encodes a lipid transfer protein called VPS13A, or chorein, associated with mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs), mitochondria-endosomes, and lipid droplets. This protein plays a crucial role in inter-organelle communication and lipid transport. Mutations in the VPS13A gene are implicated in the pathogenesis of chorea-acanthocytosis (ChAc), a rare autosomal recessive neurodegenerative disorder characterized by chorea, orofacial dyskinesias, hyperkinetic movements, seizures, cognitive impairment, and acanthocytosis. Previous mouse models of ChAc have shown variable disease phenotypes depending on the genetic background. In this study, we report the generation of a Vps13a flox allele in a pure C57BL/6N mouse background and the subsequent creation of Vps13a knockout (KO) mice via Cre-recombination. Our Vps13a KO mice exhibited increased reticulocytes but not acanthocytes in peripheral blood smears. Additionally, there were no significant differences in the GFAP- and Iba1-positive cells in the striatum, the basal ganglia of the central nervous system. Interestingly, we observed abnormal spermatogenesis leading to male infertility. These findings indicate that Vps13a KO mice are valuable models for studying male infertility and some hematological aspects of ChAc.


Assuntos
Encéfalo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuroacantocitose , Fenótipo , Testículo , Proteínas de Transporte Vesicular , Animais , Masculino , Proteínas de Transporte Vesicular/genética , Camundongos , Testículo/metabolismo , Testículo/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Neuroacantocitose/genética , Neuroacantocitose/patologia , Modelos Animais de Doenças , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Espermatogênese/genética
7.
J Cell Mol Med ; 27(11): 1557-1564, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37163371

RESUMO

VPS13A is a lipid transfer protein localized at different membrane contact sites between organelles, and mutations in the corresponding gene produce a rare neurodegenerative disease called chorea-acanthocytosis (ChAc). Previous studies showed that VPS13A depletion in HeLa cells results in an accumulation of endosomal and lysosomal markers, suggesting a defect in lysosomal degradation capacity leading to partial autophagic dysfunction. Our goal was to determine whether compounds that modulate the endo-lysosomal pathway could be beneficial in the treatment of ChAc. To test this hypothesis, we first generated a KO model using CRISPR/Cas9 to study the consequences of the absence of VPS13A in HeLa cells. We found that inactivation of VPS13A impairs cell growth, which precludes the use of isolated clones due to the undesirable selection of edited clones with residual protein expression. Therefore, we optimized the use of pool cells obtained shortly after transfection with CRISPR/Cas9 components. These cells are a mixture of wild-type and edited cells that allow a comparative analysis of phenotypes and avoids the selection of clones with residual level of VPS13A expression after long-term growth. Consistent with previous observations by siRNA inactivation, VPS13A inactivation by CRISPR/Cas9 resulted in accumulation of the endo-lysosomal markers RAB7A and LAMP1. Notably, we observed that rapamycin partially suppressed the difference in lysosome accumulation between VPS13A KO and WT cells, suggesting that modulation of the autophagic and lysosomal pathway could be a therapeutic target in the treatment of ChAc.


Assuntos
Neuroacantocitose , Doenças Neurodegenerativas , Humanos , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo , Sistemas CRISPR-Cas/genética , Células HeLa , Sirolimo/farmacologia , Doenças Neurodegenerativas/metabolismo , Lisossomos/metabolismo , Neuroacantocitose/genética , Neuroacantocitose/metabolismo
8.
Neurobiol Dis ; 187: 106292, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714309

RESUMO

Chorea-acanthocytosis (ChAc) is an inherited neurodegenerative movement disorder caused by VPS13A gene mutations leading to the absence of protein expression. The striatum is the most affected brain region in ChAc patients. However, the study of the VPS13A function in the brain has been poorly addressed. Here we generated a VPS13A knockdown (KD) model and aimed to elucidate the contribution of VPS13A to synaptic plasticity and neuronal communication in the corticostriatal circuit. First, we infected primary cortical neurons with miR30-shRNA against VPS13A and analyzed its effects on neuronal plasticity. VPS13A-KD neurons showed a higher degree of branching than controls, accompanied by decreased BDNF and PSD-95 levels, indicative of synaptic alterations. We then injected AAV-KD bilaterally in the frontal cortex and two different regions of the striatum of mice and analyzed the effects of VPS13A-KD on animal behavior and synaptic plasticity. VPS13A-KD mice showed modification of the locomotor behavior pattern, with increased exploratory behavior and hyperlocomotion. Corticostriatal dysfunction in VPS13A-KD mice was evidenced by impaired striatal long-term depression (LTD) after stimulation of cortical afferents, which was partially recovered by BDNF administration. VPS13A-KD did not lead to neuronal loss in the cortex or the striatum but induced a decrease in the neuronal release of CX3CL1 and triggered a microglial reaction, especially in the striatum. Notably, CX3CL1 administration partially restored the impaired corticostriatal LTD in VPS13A-KD mice. Our results unveil the involvement of VPS13A in neuronal connectivity modifying BDNF and CX3CL1 release. Moreover, the involvement of VPS13A in synaptic plasticity and motor behavior provides key information to further understand not only ChAc pathophysiology but also other neurological disorders.

9.
Mol Genet Genomics ; 298(4): 965-976, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37209156

RESUMO

Choreoacanthocytosis, one of the forms of neuroacanthocytosis, is caused by mutations in vacuolar protein sorting-associated protein A (VPS13A), and is often misdiagnosed with other form of neuroacanthocytosis with discrete genetic defects. The phenotypic variations among the patients with VPS13A mutations significantly obfuscates the understanding of the disease and treatment strategies. In this study, two unrelated cases were identified, exhibiting the core phenotype of neuroacanthocytosis but with considerable clinical heterogeneity. Case 1 presented with an additional Parkinsonism phenotype, whereas seizures were evident in case 2. To decipher the genetic basis, whole exome sequencing followed by validation with Sanger sequencing was performed. A known homozygous pathogenic nonsense mutation (c.799C > T; p.R267X) in exon 11 of the VPS13A gene was identified in case 1 that resulted in a truncated protein. A novel missense mutation (c.9263T > G; p.M3088R) in exon 69 of VPS13A identified in case 2 was predicted as pathogenic. In silico analysis of the p.M3088R mutation at the C-terminus of VPS13A suggests a loss of interaction with TOMM40 and may disrupt mitochondrial localization. We also observed an increase in mitochondrial DNA copy numbers in case 2. Mutation analysis revealed benign heterozygous variants in interacting partners of VPS13A such as VAPA in case 1. Our study confirmed the cases as ChAc and identified the novel homozygous variant of VPS13A (c.9263T > G; p.M3088R) within the mutation spectrum of VPS13A-associated ChAc. Furthermore, mutations in VPS13A and co-mutations in its potential interacting partner(s) might contribute to the diverse clinical manifestations of ChAc, which requires further study.


Assuntos
Neuroacantocitose , Humanos , Neuroacantocitose/genética , Neuroacantocitose/patologia , Sequenciamento do Exoma , Genes Modificadores , Mutação , Códon sem Sentido/genética , Proteínas de Transporte Vesicular/genética
10.
Mov Disord ; 38(12): 2163-2172, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37670483

RESUMO

BACKGROUND: Vacuolar protein sorting 13 homolog A (VPS13A) disease, historically known as chorea-acanthocytosis, is a rare neurodegenerative disorder caused by biallelic mutations in VPS13A, usually resulting in reduced or absent levels of its protein product, VPS13A. VPS13A localizes to contact sites between subcellular organelles, consistent with its recently identified role in lipid transfer between membranes. Mutations are associated with neuronal loss in the striatum, most prominently in the caudate nucleus, and associated marked astrogliosis. There are no other known disease-specific cellular changes (eg, protein aggregation), but autopsy reports to date have been limited, often lacking genetic or biochemical diagnostic confirmation. OBJECTIVE: The goal of this study was to characterize neuropathological findings in the brains of seven patients with VPS13A disease (chorea-acanthocytosis). METHODS: In this study, we collected brain tissues and clinical data from seven cases of VPS13A for neuropathological analysis. The clinical diagnosis was confirmed by the presence of VPS13A mutations and/or immunoblot showing the loss or reduction of VPS13A protein. Tissues underwent routine, special, and immunohistochemical staining focused on neurodegeneration. Electron microscopy was performed in one case. RESULTS: Gross examination showed severe striatal atrophy. Microscopically, there was neuronal loss and astrogliosis in affected regions. Luxol fast blue staining showed variable lipid accumulation with diverse morphology, which was further characterized by electron microscopy. In some cases, rare degenerating p62- and ubiquitin-positive cells were present in affected regions. Calcifications were present in four cases, being extensive in one. CONCLUSIONS: We present the largest autopsy series of biochemically and genetically confirmed VPS13A disease and identify novel histopathological findings implicating abnormal lipid accumulation. © 2023 International Parkinson and Movement Disorder Society.


Assuntos
Neuroacantocitose , Humanos , Autopsia , Núcleo Caudado/metabolismo , Gliose , Lipídeos , Neuroacantocitose/genética , Neuroacantocitose/diagnóstico , Neuroacantocitose/patologia , Proteínas de Transporte Vesicular/genética
11.
Mov Disord ; 38(8): 1535-1541, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37307400

RESUMO

BACKGROUND: Chorea-acanthocytosis (ChAc) is associated with mutations of VPS13A, which encodes for chorein, a protein implicated in lipid transport at intracellular membrane contact sites. OBJECTIVES: The goal of this study was to establish the lipidomic profile of patients with ChAc. METHODS: We analyzed 593 lipid species in the caudate nucleus (CN), putamen, and dorsolateral prefrontal cortex (DLPFC) from postmortem tissues of four patients with ChAc and six patients without ChAc. RESULTS: We found increased levels of bis(monoacylglycerol)phosphate, sulfatide, lysophosphatidylserine, and phosphatidylcholine ether in the CN and putamen, but not in the DLPFC, of patients with ChAc. Phosphatidylserine and monoacylglycerol were increased in the CN and N-acyl phosphatidylserine in the putamen. N-acyl serine was decreased in the CN and DLPFC, whereas lysophosphatidylinositol was decreased in the DLPFC. CONCLUSIONS: We present the first evidence of altered sphingolipid and phospholipid levels in the brains of patients with ChAc. Our observations are congruent with recent findings in cellular and animal models, and implicate defects of lipid processing in VPS13A disease pathophysiology. © 2023 International Parkinson and Movement Disorder Society. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Neuroacantocitose , Animais , Humanos , Neuroacantocitose/genética , Neuroacantocitose/metabolismo , Fosfolipídeos/metabolismo , Fosfatidilserinas/metabolismo , Proteínas de Transporte Vesicular/genética , Encéfalo/metabolismo
12.
BMC Neurol ; 23(1): 350, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794323

RESUMO

BACKGROUND: Chorea-acanthocytosis (ChAc) is a rare hereditary autosomal recessive neurodegenerative disorder caused by pathogenic variants of the Vacuolar Protein Sorting 13 homolog A (VPS13A) gene. The variant spectrum of VPS13A has not been completely elucidated. This study reports two novel heterozygous VPS13A pathogenic variants in ChAc that expand the variant spectrum of VPS13A. CASE PRESENTATION: We described a case of a 29-year-old man with typical clinical manifestations of ChAc, including chorea, orofacial lingual dyskinesia, vocal tics, elevated serum biochemical indicators, increased acanthocytes in peripheral blood, and caudate nucleus atrophy. Next-generation sequencing revealed two heterozygous variants of VPS13A: a nonsense variant (NM_033305.2: c.8215G > T, p. Glu2739Ter) and a deletion variant in the exons 25-31. CONCLUSION: The identified nonsense variant gives rise to premature translation termination, while the deletion variant is expected to cause a significant in-frame deletion of amino acid residues in the encoded protein. Both variants are considered to be pathogenic and result in loss-of-function proteins. These findings have implications for the genetic counseling of patients with VPS13A variants.


Assuntos
Discinesias , Neuroacantocitose , Tiques , Masculino , Humanos , Adulto , Neuroacantocitose/genética , Proteínas de Transporte Vesicular/genética , Núcleo Caudado/metabolismo , Núcleo Caudado/patologia
13.
Int J Mol Sci ; 23(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35563497

RESUMO

Mutations in human VPS13A-D genes result in rare neurological diseases, including chorea-acanthocytosis. The pathogenesis of these diseases is poorly understood, and no effective treatment is available. As VPS13 genes are evolutionarily conserved, the effects of the pathogenic mutations could be studied in model organisms, including yeast, where one VPS13 gene is present. In this review, we summarize advancements obtained using yeast. In recent studies, vps13Δ and vps13-I2749 yeast mutants, which are models of chorea-acanthocytosis, were used to screen for multicopy and chemical suppressors. Two of the suppressors, a fragment of the MYO3 and RCN2 genes, act by downregulating calcineurin activity. In addition, vps13Δ suppression was achieved by using calcineurin inhibitors. The other group of multicopy suppressors were genes: FET4, encoding iron transporter, and CTR1, CTR3 and CCC2, encoding copper transporters. Mechanisms of their suppression rely on causing an increase in the intracellular iron content. Moreover, among the identified chemical suppressors were copper ionophores, which require a functional iron uptake system for activity, and flavonoids, which bind iron. These findings point at areas for further investigation in a higher eukaryotic model of VPS13-related diseases and to new therapeutic targets: calcium signalling and copper and iron homeostasis. Furthermore, the identified drugs are interesting candidates for drug repurposing for these diseases.


Assuntos
Neuroacantocitose , Doenças Neurodegenerativas , Proteínas de Saccharomyces cerevisiae , Sinalização do Cálcio , Proteínas de Ligação ao Cálcio/metabolismo , Cobre/metabolismo , Proteínas de Transporte de Cobre , Humanos , Ferro/metabolismo , Proteínas de Ligação ao Ferro/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
14.
Int J Mol Sci ; 22(23)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34884823

RESUMO

Loss-of-function mutations in the human vacuolar protein sorting the 13 homolog A (VPS13A) gene cause Chorea-acanthocytosis (ChAc), with selective degeneration of the striatum as the main neuropathologic feature. Very little is known about the VPS13A expression in the brain. The main objective of this work was to assess, for the first time, the spatiotemporal distribution of VPS13A in the mouse brain. We found VPS13A expression present in neurons already in the embryonic stage, with stable levels until adulthood. VPS13A mRNA and protein distributions were similar in the adult mouse brain. We found a widespread VPS13A distribution, with the strongest expression profiles in the pons, hippocampus, and cerebellum. Interestingly, expression was weak in the basal ganglia. VPS13A staining was positive in glutamatergic, GABAergic, and cholinergic neurons, but rarely in glial cells. At the cellular level, VPS13A was mainly located in the soma and neurites, co-localizing with both the endoplasmic reticulum and mitochondria. However, it was not enriched in dendritic spines or the synaptosomal fraction of cortical neurons. In vivo pharmacological modulation of the glutamatergic, dopaminergic or cholinergic systems did not modulate VPS13A concentration in the hippocampus, cerebral cortex, or striatum. These results indicate that VPS13A has remarkable stability in neuronal cells. Understanding the distinct expression pattern of VPS13A can provide relevant information to unravel pathophysiological hallmarks of ChAc.


Assuntos
Encéfalo/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Encéfalo/citologia , Encéfalo/patologia , Células Cultivadas , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Retículo Endoplasmático/metabolismo , Neurônios GABAérgicos/metabolismo , Hipocampo/metabolismo , Hibridização in Situ Fluorescente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Neuritos/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Transporte Vesicular/genética
15.
Int J Mol Sci ; 22(22)2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34830155

RESUMO

VPS13 proteins are evolutionarily conserved. Mutations in the four human genes (VPS13A-D) encoding VPS13A-D proteins are linked to developmental or neurodegenerative diseases. The relationship between the specific localization of individual VPS13 proteins, their molecular functions, and the pathology of these diseases is unknown. Here we used a yeast model to establish the determinants of Vps13's interaction with the membranes of Golgi apparatus. We analyzed the different phenotypes of the arf1-3 arf2Δ vps13∆ strain, with reduced activity of the Arf1 GTPase, the master regulator of Golgi function and entirely devoid of Vps13. Our analysis led us to propose that Vps13 and Arf1 proteins cooperate at the Golgi apparatus. We showed that Vps13 binds to the Arf1 GTPase through its C-terminal Pleckstrin homology (PH)-like domain. This domain also interacts with phosphoinositol 4,5-bisphosphate as it was bound to liposomes enriched with this lipid. The homologous domain of VPS13A exhibited the same behavior. Furthermore, a fusion of the PH-like domain of Vps13 to green fluorescent protein was localized to Golgi structures in an Arf1-dependent manner. These results suggest that the PH-like domains and Arf1 are determinants of the localization of VPS13 proteins to the Golgi apparatus in yeast and humans.


Assuntos
Fator 1 de Ribosilação do ADP/metabolismo , Complexo de Golgi/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Fator 1 de Ribosilação do ADP/genética , Clatrina/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Microscopia Confocal , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Biológicos , Mutação , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Ligação Proteica , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Temperatura
16.
BMC Med Genet ; 21(1): 47, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131761

RESUMO

BACKGROUND: Choreoacanthocytosis (ChAc), is a rare neurodegenerative disease, characterized by movement disorders and acanthocytosis in the peripheral blood smears, and various neurological, neuropsychiatric and neuromuscular signs. It is caused by mutations in VPS13A gene with autosomal recessive pattern of inheritance. CASE PRESENTATION: Here we report two patients belonging to a consanguineous Moroccan family who present with movement disorder pathology. They were suspected to have choreoacanthocytosis according to biological, clinical and radiological finding. Thus, whole-exome sequencing was performed for precise diagnosis and identified a homozygous novel nonsense mutation c.337C > T (p.Gln113*) in exon 5 of VPS13A in the two affected siblings. CONCLUSION: Here, we report a novel nonsense p.Gln113* mutation in VPS13A identified by whole-exome sequencing, which caused ChAc in a Moroccan family. This is the first description of ChAc in Morocco with genetic confirmation, that expands the mutation diversity of VPS13A and provide clinical, neuroimaging and deep brain stimulation findings.


Assuntos
Neuroacantocitose/genética , Polimorfismo de Nucleotídeo Único , Proteínas de Transporte Vesicular/genética , Adulto , Códon sem Sentido , Consanguinidade , Feminino , Humanos , Marrocos , Neuroacantocitose/patologia , Linhagem , Convulsões/complicações , Convulsões/genética , Irmãos , Espasmo/complicações , Espasmo/genética
17.
J Integr Neurosci ; 18(2): 197-201, 2019 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-31321962

RESUMO

Neuroacanthocytosis is a rare progressive neurodegenerative disease, including Chorea-acanthocytosis, McLeod syndrome, Huntington's disease-like 2, and pantothenate kinase-associated neurodegeneration, where Chorea-acanthocytosis occupies the main entity of this disease group. Here, a classic case of Chorea-acanthocytosis is reported that exhibited gradually deteriorating abnormal movements of limbs and face, swallowing difficulty, and lip and cheek biting for the past two years. Peripheral blood smears revealed that 35% of the red blood cells were acanthocytes and electron microcopy scans clearly showed the morphology of acanthocytes. VPS13A gene sequencing found a heterozygous novel VPS13A gene mutation (c.80dupT). Brain magnetic resonance imaging scans showed moderate anterior horn dilation of lateral ventricles and bilateral atrophy of the head of caudate nucleus. Several suggestive features are summarized to provide diagnostic clues for Chorea-acanthocytosis and facilitate future diagnosis and treatment.


Assuntos
Encéfalo/patologia , Neuroacantocitose/diagnóstico , Neuroacantocitose/genética , Acantócitos/patologia , Adulto , Atrofia/patologia , Encéfalo/diagnóstico por imagem , Humanos , Masculino , Neuroacantocitose/patologia
18.
Biochem Biophys Res Commun ; 503(2): 915-920, 2018 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-29928881

RESUMO

Chorea-acanthocytosis (ChAc) is an autosomal recessive hereditary disease characterized by neurodegeneration in the striatum and acanthocytosis caused by loss-of-function mutations in the Vacuolar Protein Sorting 13 Homolog A (VPS13A) gene, which encodes chorein. We previously produced a ChAc-model mouse with a homozygous deletion of exons 60-61 in Vps13a, which corresponded to the human disease mutation. We found that male ChAc-model mice exhibited complete infertility as a result of severely diminished sperm motility. Immunocytochemical study revealed that chorein-like immunoreactivity is abundant only in the midpiece, mitochondria-rich region, of the sperm of wild type mice. They showed no significant differences from wild types in terms of the adenosine 5'-triphosphate (ATP) concentration of their sperm, sperm count, or sexual activity. Electron microscopy revealed abnormal ultrastructural morphology of the mitochondria in the midpiece of sperm from ChAc-model mice. These results suggest that chorein is essential in mouse sperm for the maintenance of ultrastructural mitochondrial morphology and sperm motility.


Assuntos
Modelos Animais de Doenças , Infertilidade Masculina/genética , Mitocôndrias/metabolismo , Neuroacantocitose/genética , Peça Intermédia do Espermatozoide/metabolismo , Motilidade dos Espermatozoides/genética , Animais , Humanos , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Mutação , Proteínas do Tecido Nervoso/genética , Peça Intermédia do Espermatozoide/ultraestrutura , Proteínas de Transporte Vesicular
19.
FASEB J ; 30(11): 3726-3732, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27468757

RESUMO

The autophagy pathway has recently been implicated in several neurodegenerative diseases. Recently, it was reported that chorein-depleted cells showed accumulation of autophagic markers and impaired autophagic flux. Here, we demonstrate that chorein overexpression preserves cell viability from starvation-induced cell death in human embryonic kidney 293 (HEK293) cells. Subsequent coimmunoprecipitation and reverse coimmunoprecipitation assays using extracts from chorein that stably overexpressed HEK293 cells revealed that chorein interacts with α-tubulin and histone deacetylase 6, a known α-tubulin deacetylater and central component of basal autophagy. Indeed, acetylated α-tubulin immunoreactivity was significantly decreased in chorein that stably overexpressed HEK293 cells. These results suggest that chorein/histone deacetylase 6/α-tubulin interactions may play an important role in starvation-induced cell stress, and their disruption may be one of the molecular pathogenic mechanisms of chorea-acanthocytosis.-Sasaki, N., Nakamura, M., Kodama, A., Urata, Y., Shiokawa, N., Hayashi, T., Sano, A. Chorein interacts with α-tubulin and histone deacetylase 6, and overexpression preserves cell viability during nutrient deprivation in human embryonic kidney 293 cells.


Assuntos
Histona Desacetilases/metabolismo , Rim/embriologia , Rim/metabolismo , Tubulina (Proteína)/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Acetilação , Animais , Autofagia/fisiologia , Sobrevivência Celular , Células Cultivadas , Células HEK293 , Humanos , Imunoprecipitação/métodos , Camundongos Knockout
20.
Orv Hetil ; 158(42): 1681-1684, 2017 Oct.
Artigo em Húngaro | MEDLINE | ID: mdl-29037056

RESUMO

In a patient with marked symptoms of Huntington disease after the huntingtin testing, which gave normal result, a whole exome sequencing (WES) has been performed based on an international collaboration. A homozygous G>A nucleotid change in the exon 34 of the VPS13A gene has been detected with WES, a mutation resulting in a premature stop codon at the position 1301. This change is a known pathogenic mutation. The aim of this article is to draw attention on the importance of the WES in the diagnosis of rare neurological diseases without any specific symptoms. Orv Hetil. 2017; 158(42): 1681-1684.


Assuntos
Neuroacantocitose/diagnóstico , Proteínas de Transporte Vesicular/genética , Sequência de Bases , Humanos , Neuroacantocitose/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
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