Progressive myoclonus epilepsy type 1 (EPM1), also known as Unverricht-Lundborg disease, is one of the rare forms of epilepsy that shows a clear pattern of autosomal recessive inheritance. The gene defective in this disease was linked to the distal tip of chromosome 21, in band q22.3. In this study, we have collected 93 samples from 15 EPM1 families and 5 affected individuals as the basis for identifying the EPM1 gene. We have also constructed a 770 kb cosmid and bacterial artificial chromosome contig covering the candidate EPM1 region, and have isolated expressed sequences from this contig. For three of the genes that we isolated (GT335, GT334, and PWP2), we have identified and sequenced a full-length cDNA, identified the putative protein, assessed the expression pattern of the gene by Northern blot, determined the exon/intron structure of the gene, characterized basepair polymorphisms within each gene, and finally excluded each of these genes as the one defective in EPM1 patients. Using these new polymorphisms, and others that were available and that we had identified, we were able to construct detailed haplotypes on each of the affected EPM1 chromosomes, to help pinpoint, the location of the EPM1 gene, and help estimate the number of different mutations we might have in our collection. / While these studies were underway, another group identified the cystatin B (STFB) gene as that defective in EPM1. This allowed us to directly test this gene for mutations in our collection of EPM1 patients. We could identify four different mutations in the STFB gene, the most common of which consisted of a variable length insertion in the 5 ' flanking region of the gene, and which was previously undescribed. This mutation, which is found in 78% of unrelated EPM1 chromosomes we studied, showed some level of meiotic instability, and mapped to a polymorphic 12-bp GC-rich repeat. Using a combination of PCR and Southern blotting assays, we could accurately diagnose nearly 100% of all EPM1 patients. This represents a significant step forward in our ability to diagnose this disease at the molecular level, and should allow a more precise definition of the progressive myoclonus epilepsies, as a whole.

No description available.

Myoclonus dystonia (MD) is a rare autosomal-dominant combined dystonia movement disorder characterised by quick, involuntary muscle jerks (myoclonus) paired with sustained muscular contraction (dystonia). Although known to be genetically heterogeneous, the most common genetic factor is mutations within SGCE, the gene encoding ε-sarcoglycan, accounting for approximately 45% of cases. Previous linkage analyses conducted on a family displaying inherited MD without SGCE mutations lead to the identification of another critical region, DYT15. Preliminary data suggested that mutations within the long non-coding RNA (lncRNA) CD108131, found within the DYT15 locus, resulted in decreased expression of both the SGCE transcript, as well as the SGCE protein. Validation of the remaining variants of interest yielded no new candidate genes. A low coverage area coinciding with the entire sequence of TMEM200C was discovered, however subsequent sequencing data revealed no potential disease-causing variants. Therefore, to further characterise the relationship between CD108131 and SGCE suggested by the preliminary data, a CRISPR-Cas9 knockout was developed in HEK293 cells using a double-cut strategy that allowed for complete excision of the CD108131 gene. Stable CD108131 knockout mutant cell lines were examined for differences in gene expression. QRT-PCR analysis was conducted and revealed a significant decrease in SGCE expression in the absence of CD108131. Additionally, expression also trended towards a decrease for ZBTB14, however ARHGAP28 and RPPH1 were not significantly altered. This data demonstrates that the lncRNA CD108131 is likely to have a regulatory effect on SGCE, and perhaps ZBTB14, transcription.

Orientadores: Marilisa Mantovani Guerreiro, Maria Augusta Montenegro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T12:47:22Z (GMT). No. of bitstreams: 1 Preto_PaulaMaria_M.pdf: 6934972 bytes, checksum: e8531a69068b5848bc523e1dce28ee1c (MD5) Previous issue date: 2010 / Resumo: A Epilepsia Mioclônica Grave da Infância ou Síndrome de Dravet (SDr) e a Epilepsia Miclônico-Astática ou Síndrome de Doose (SDo) são epilepsias raras da infância, que cursam com crises epilépticas refratárias, nas quais há predomínio das mioclonias, e que podem levar à deterioração do desenvolvimento neuropsicomotor. Em aproximadamente 2/3 dos pacientes com SDr encontra-se mutação da subunidade alfa do canal de sódio (SCN1A). Nosso objetivo neste estudo foi de avaliar as características clínicas e eletrencefalográficas na SDr e SDo. Avaliamos 14 pacientes com SDr, com idade de início das crises entre três e 18 meses (média: 9 ± 4 meses), sendo quatro do sexo masculino e 10 do sexo feminino. Avaliamos também 13 pacientes com Sdo, com idade de início das crises entre dois e seis anos (média: 3,02 ± 1,22 anos), sendo sete do sexo masculino e seis do sexo feminino. Em todos os pacientes foram realizados exame neurológico tradicional, EEG (2 a 8 exames por paciente), RM crânio e Escala de Vineland, que estabelece o nível de maturidade social e psicomotora da criança, para permitir a avaliação do comportamento adaptativo nas áreas relacionadas à comunicação, atividade de vida diária, socialização e habilidades motoras fina e grossa. Foram encontradas alterações no exame neurológico em todos os pacientes com SDr e quatro pacientes com SDo. Ocorreu deterioração do comportamento adaptativo em todos os pacientes com SDr e oito pacientes com SDo. Nosso estudo encontrou ataxia, sinais leves de liberação piramidal, hiperatividade, espectro autístico nos pacientes com SDr e SDo. Foi observada lentificação da atividade de base e atividade epileptiforme no EEG em dez pacientes com SDr e ritmo de Doose em nove pacientes com SDo, além de atividade epileptiforme em todos os pacientes com SDo. Observamos alterações epileptiformes focais e generalizadas na SDr e alterações epileptiformes predominantemente generalizadas na SDo. A pesquisa da mutação da subunidade alfa do canal de sódio (SCN1A) foi realizada em 10 pacientes com SDr e em 10 pacientes com SDo e foi encontrada a mutação em seis pacientes com SDr, sendo normal nos demais. Nas SDr e SDo os nossos dados concordaram com os achados da literatura em relação aos achados clínicos, exame neurológico, EEG, exames de imagem, genotipagem e tratamento; no entanto, foi discordante da literatura quanto à distribuição quanto ao sexo na SDr, o que pode ser justificado pela nossa casuística modesta. A aplicação da Escala de Vineland foi dado inovador nos estudos da SDr e SDo. Acreditamos que nossa pesquisa permitiu melhor caracterização dessas duas síndromes epilépticas e mostrou resultados semelhantes aos estudos europeus, onde foram originalmente descritos / Abstract: Severe Myoclonic Epilepsy of Infancy or Dravet syndrome (SMEI) and Mioclonic-Astatic Epilepsy or Doose Syndrome (MAE) are rare childhood epilepsies, which occur with refractory seizures, where there is a predominance of myoclonic seizures. Deterioration of the neuropsychomotor development usually occurs. Approximately two thirds of patients of the patients with SMEI may have mutation of the alpha subunit of the sodium channel (SCN1A). Our objective was to evaluate the clinical and electroencephalographic features of SMEI and MAE. We evaluated 14 patients with seizure onset between three and 18 months of age with SMEI (mean age: 9 ± 4 months). Four were male and 10 female. We also evaluated 13 patients with seizure onset between two and six years with MAE (mean age: 3, 02 ± 1, 22 years). Seven were male and six female. We performed traditional neurological examination, EEG (2-8 exams per patient), cerebral MRI and Vineland Scale, that establishes the level of psychomotor and social maturity of the child to allow an assessment of the adaptive behavior in areas related to communication, activity of daily living, socialization and fine and gross motor skills. Our study found changes in the neurological examination of 14 patients with SMEI and four patients with MAE. We observed slowing of background activity and epileptiform activity in 10 patients with SMEI. Doose rhythm was detected in nine patients with MAE and epileptiform activity in all patients with MAE. Deterioration of adaptive behavior occurred in all patients with SMEI and eight patients with MAE. Our study showed ataxia, mild signs of pyramidal liberation, hyperactivity and autistic spectrum in patients with SMEI and MAE. We observed focal and generalized epileptiform discharges in patients with SMEI and disturbance was predominantly generalized in patients with MAE. The study of mutation of the alpha subunit of the sodium channel (SCN1A) was performed in 10 patients with SMEI and 10 patients with MAE and the mutation was found in six patients with SMEI and the remaining examination was normal. In SMEI and EMA our data are in keeping with the findings of the literature regarding clinical, neurological examination, EEG, cerebral MRI, genotyping and treatment; except for gender distribution in the SMEI, which can be attributed to the small study group. The assessment with Vineland scale brought a new light to the understanding of SMEI and MAE. We believe that our research has enabled better characterization of these two epileptic syndromes, showing that the results are similar to those from Europe, where they were originally described / Mestrado / Neurologia / Mestre em Ciências Médicas

京都大学 / 新制・課程博士 / 博士(医学) / 甲第23774号 / 医博第4820号 / 新制||医||1057(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 伊佐 正, 教授 高橋 淳, 教授 井上 治久 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Myoclonus Dystonia (MD) is an autosomal dominant movement disorder characterized by bilateral myoclonic jerks paired with dystonia 1. Mutations have been mapped to the ε-sarcoglycan (SGCE) gene in about 40% of patients 2,92. The purpose of this project was to examine the properties of SGCE in the central nervous system (CNS) and use this knowledge to elucidate the pathology of MD. Although Sgce is a member of the sarcoglycan complex (SGC) in other tissues, little is known about its interactions in the CNS. The vast majority of mutations in SGCE alter the translational reading frame. Proteins arising from these rare mutations are less stable than the wild type (WT) and undergo preferential degradation via the ubiquitin proteasome system 3. As this locus is maternally imprinted, patients with MD are effectively null for sgce expression 73,91. Therefore, Sgce knock out (KO) models should approximate MD conditions both in vivo and in vitro. As there are no current treatments for MD, in sight into the pathology of the disease will aid in eventual treatments and help bring patients some relief by finally understanding their disease. Since a large percentage of MD patients are without the sgce protein, identifying what this protein’s function is and how its absence effects normal processing in the brain should help to identify the underlying cellular pathology which produces the MD phenotype. This research was performed under the hypothesis that, in neuronal cells, sgce interacts with a group of proteins that together play a role in stabilization and localization of ion channels and signaling proteins at the cell membrane. The aims were to: (1) Build a MD mouse model with either a conditional knock-out (cKO) or a conditional gene repair (cGR) mutation; (2) Use neuroblastoma cells to identify the other proteins which interact with sgce in neurons, and; (3) Determine if there is a disruption of the localization of the sgce-complex members due to the loss of sgce. Recombineering was used to complete the constructs for two transgenic mouse models: One model for the KO of exon 4 of sgce and one for the cGR in intron 1. Primary neurosphere lines from two previously generated chimeras were developed, as well as from a WT mouse. These neurosphere cell lines allowed comparisons of RT-PCR results from a heterogeneous neurological cell population to neuroblastoma cell lines. mRNA is present in neuronal cells for many of the DGC associated proteins. It was confirmed that the KD of sgce results in a reduction of nNOS protein and in increased proliferation of NIE cells. By using a nitrite/nitrate assay as well as studies with L-NAME, it was confirmed that this increased proliferation was in fact due to a lack of nNOS function. These proliferation changes did not occur in N2A cells, which do not express high levels of nNOS during proliferation, further confirming nNOS’s role in the proliferation changes. Using qRT-PCR, KD of sgce was shown to result in significant changes in the transcript levels for many DGC associated proteins. This suggests that a DGC-like complex is forming in neuronal cells. Also, as a result of difficulties with the research, it became clear that over-expression of sgce causes cell death. This observation was quantified using cell counts and TUNEL staining, both showing significant results. Additionally, several new constructs were created which will hopefully be of use for future students wanting to study sgce’s functions. New shRNA targeting sgce and sgcb have been made and both constructs result in reducing the expression of sgce. Seven different flag-tagged sgces have been created and some of these have been transferred into a tet-inducible system, which should circumvent the problem of over-expression. Finally GFP-tagged constructs for sgce and sgcb have been made and pooled clones have been developed. These tools will hopefully enable future students to continue to tease apart sgce’s function(s).

Myoclonus Dystonia (MD) is an autosomal dominant movement disorder characterized by bilateral myoclonic jerks paired with dystonia 1. Mutations have been mapped to the ε-sarcoglycan (SGCE) gene in about 40% of patients 2,92. The purpose of this project was to examine the properties of SGCE in the central nervous system (CNS) and use this knowledge to elucidate the pathology of MD. Although Sgce is a member of the sarcoglycan complex (SGC) in other tissues, little is known about its interactions in the CNS. The vast majority of mutations in SGCE alter the translational reading frame. Proteins arising from these rare mutations are less stable than the wild type (WT) and undergo preferential degradation via the ubiquitin proteasome system 3. As this locus is maternally imprinted, patients with MD are effectively null for sgce expression 73,91. Therefore, Sgce knock out (KO) models should approximate MD conditions both in vivo and in vitro. As there are no current treatments for MD, in sight into the pathology of the disease will aid in eventual treatments and help bring patients some relief by finally understanding their disease. Since a large percentage of MD patients are without the sgce protein, identifying what this protein’s function is and how its absence effects normal processing in the brain should help to identify the underlying cellular pathology which produces the MD phenotype. This research was performed under the hypothesis that, in neuronal cells, sgce interacts with a group of proteins that together play a role in stabilization and localization of ion channels and signaling proteins at the cell membrane. The aims were to: (1) Build a MD mouse model with either a conditional knock-out (cKO) or a conditional gene repair (cGR) mutation; (2) Use neuroblastoma cells to identify the other proteins which interact with sgce in neurons, and; (3) Determine if there is a disruption of the localization of the sgce-complex members due to the loss of sgce. Recombineering was used to complete the constructs for two transgenic mouse models: One model for the KO of exon 4 of sgce and one for the cGR in intron 1. Primary neurosphere lines from two previously generated chimeras were developed, as well as from a WT mouse. These neurosphere cell lines allowed comparisons of RT-PCR results from a heterogeneous neurological cell population to neuroblastoma cell lines. mRNA is present in neuronal cells for many of the DGC associated proteins. It was confirmed that the KD of sgce results in a reduction of nNOS protein and in increased proliferation of NIE cells. By using a nitrite/nitrate assay as well as studies with L-NAME, it was confirmed that this increased proliferation was in fact due to a lack of nNOS function. These proliferation changes did not occur in N2A cells, which do not express high levels of nNOS during proliferation, further confirming nNOS’s role in the proliferation changes. Using qRT-PCR, KD of sgce was shown to result in significant changes in the transcript levels for many DGC associated proteins. This suggests that a DGC-like complex is forming in neuronal cells. Also, as a result of difficulties with the research, it became clear that over-expression of sgce causes cell death. This observation was quantified using cell counts and TUNEL staining, both showing significant results. Additionally, several new constructs were created which will hopefully be of use for future students wanting to study sgce’s functions. New shRNA targeting sgce and sgcb have been made and both constructs result in reducing the expression of sgce. Seven different flag-tagged sgces have been created and some of these have been transferred into a tet-inducible system, which should circumvent the problem of over-expression. Finally GFP-tagged constructs for sgce and sgcb have been made and pooled clones have been developed. These tools will hopefully enable future students to continue to tease apart sgce’s function(s).

Myoclonus Dystonia (MD) is an autosomal dominant movement disorder characterized by bilateral myoclonic jerks paired with dystonia 1. Mutations have been mapped to the ε-sarcoglycan (SGCE) gene in about 40% of patients 2,92. The purpose of this project was to examine the properties of SGCE in the central nervous system (CNS) and use this knowledge to elucidate the pathology of MD. Although Sgce is a member of the sarcoglycan complex (SGC) in other tissues, little is known about its interactions in the CNS. The vast majority of mutations in SGCE alter the translational reading frame. Proteins arising from these rare mutations are less stable than the wild type (WT) and undergo preferential degradation via the ubiquitin proteasome system 3. As this locus is maternally imprinted, patients with MD are effectively null for sgce expression 73,91. Therefore, Sgce knock out (KO) models should approximate MD conditions both in vivo and in vitro. As there are no current treatments for MD, in sight into the pathology of the disease will aid in eventual treatments and help bring patients some relief by finally understanding their disease. Since a large percentage of MD patients are without the sgce protein, identifying what this protein’s function is and how its absence effects normal processing in the brain should help to identify the underlying cellular pathology which produces the MD phenotype. This research was performed under the hypothesis that, in neuronal cells, sgce interacts with a group of proteins that together play a role in stabilization and localization of ion channels and signaling proteins at the cell membrane. The aims were to: (1) Build a MD mouse model with either a conditional knock-out (cKO) or a conditional gene repair (cGR) mutation; (2) Use neuroblastoma cells to identify the other proteins which interact with sgce in neurons, and; (3) Determine if there is a disruption of the localization of the sgce-complex members due to the loss of sgce. Recombineering was used to complete the constructs for two transgenic mouse models: One model for the KO of exon 4 of sgce and one for the cGR in intron 1. Primary neurosphere lines from two previously generated chimeras were developed, as well as from a WT mouse. These neurosphere cell lines allowed comparisons of RT-PCR results from a heterogeneous neurological cell population to neuroblastoma cell lines. mRNA is present in neuronal cells for many of the DGC associated proteins. It was confirmed that the KD of sgce results in a reduction of nNOS protein and in increased proliferation of NIE cells. By using a nitrite/nitrate assay as well as studies with L-NAME, it was confirmed that this increased proliferation was in fact due to a lack of nNOS function. These proliferation changes did not occur in N2A cells, which do not express high levels of nNOS during proliferation, further confirming nNOS’s role in the proliferation changes. Using qRT-PCR, KD of sgce was shown to result in significant changes in the transcript levels for many DGC associated proteins. This suggests that a DGC-like complex is forming in neuronal cells. Also, as a result of difficulties with the research, it became clear that over-expression of sgce causes cell death. This observation was quantified using cell counts and TUNEL staining, both showing significant results. Additionally, several new constructs were created which will hopefully be of use for future students wanting to study sgce’s functions. New shRNA targeting sgce and sgcb have been made and both constructs result in reducing the expression of sgce. Seven different flag-tagged sgces have been created and some of these have been transferred into a tet-inducible system, which should circumvent the problem of over-expression. Finally GFP-tagged constructs for sgce and sgcb have been made and pooled clones have been developed. These tools will hopefully enable future students to continue to tease apart sgce’s function(s).

Thesis (DMed (Medicine. Internal Medicine))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Progressive Myoclonic Epilepsies (PME) are characterized by progressive neurological impairment with myoclonus, seizures and dementia. In contradistinction, Familial Adult Myoclonic Epilepsy (FAME) is characterized by a benign course with rare seizures and cortical tremor. Both conditions have neurophysiological features suggestive of a cortical origin for their myoclonus. This dissertation reports on a novel form of PME. Many of those who were affected had no or minimal progression of their illness, low seizure frequency and were cognitively intact, suggestive of non-progressive disorders linked to the FAME loci. The majority of patients had features of cortical myoclonus, with generalized spike and wave discharges on electroencephalography, enlarged evoked potentials, enhanced C reflexes, and evidence of cortical excitability with magnetic stimulation. However, there was evidence of cerebellar dysfunction both pathologically and on imaging. With regard to similar conditions, dentatorubral pallidoluysian atrophy and Unverricht-Lundborg syndrome were excluded by linkage analysis. Similarly, linkage was not present for either the FAME 1 or FAME 2 loci. This syndrome is both clinically and genetically novel, and has a nosology which is difficult to characterize, in which the condition appears to lie on the spectrum between FAME and PME. The dissociation between the pathological and radiological findings which suggest subcortical dysfunction, and the neurophysiological findings of cortical myoclonus is striking. Review of the literature associated with the neurophysiology of related conditions associated with PME and FAME suggests that: 1. The assumption that generalized forms of myoclonic disorders represent multifocal forms of focal cortical discharges is an oversimplification. 2. The dissociation between initial and later components of the evoked potential is less robust than is generally supposed, and that subcortical inputs may affect later components of the evoked potential. 3. In a high proportion of cases the latency from cortical spike discharge to myoclonic jerk obtained with jerk locked averaging is incompatible with a cortical origin for the spike discharge. 4. The proposal that myoclonus is a form of long latency reflex and that myoclonus represents a reflex arising from subclinical sensory input, is unproven. / AFRIKAANSE OPSOMMING: Progressiewe Miokloniese Epilepsie (PME) word gekenmerk deur progressiewe neurologiese agteruitgang met mioklonus, konvulsies en demensie. Daarenteen word Familiële Volwasse Miokloniese Epilepsie (FAME) gekenmerk deur 'n benigne verloop met ongereelde konvulsies en kortikale tremor. Beide entiteite het neurofisiologiese kenmerke suggestief van 'n kortikale oorsprong vir die mioklonus. Hierdie manuskrip beskryf 'n nuwe vorm van PME. Baie van die aangetaste persone toon geen of min agteruitgang van die siekte oor tyd nie, met 'n lae frekwensie van konvulsies en is kognitief intak, wat suggestief is van 'n nie-progressiewe siekte gekoppel aan die FAME loci. Die oorgrote meerderheid van pasiente het kenmerke van kortikale mioklonus gehad, met algemene spits en boog ontladings op elektroensefalografie, hoë amplitude ontlokte potensiale, versterkte C-reflekse, en tekens van kortikale eksiteerbaarheid met magnetiese stimulasie. Met neurobeelding en patologie was daar egter bewyse van serebellêre disfunksie. Soortgelyke toestande, naamlik dentatorubro-pallidoluysiese atrofie en Unverricht-Lundborg sindroom is uitgeskakel deur middel van koppelingsanalise. Koppeling met die FAME1 of FAME2 loci kon ook nie aangetoon word nie. Die sindroom is beide klinies sowel as geneties nuut en het 'n nosologie wat moeilik gekaraktiseer kan word. Dit wil voorkom of die siekte op 'n spektrum lê tussen FAME en PME. Die dissosiasie tussen die patologiese en radiologiese bevindinge, wat suggestief is van subkortikale disfunksie, en die neurofisiologiese bevindinge van kortikale mioklonus is opmerklik. ’n Oorsig van die literatuur in verband met die neurofisiologie van toestande geassosieer met PME en FAME suggesteer die volgende: 1. Die aanname dat algemene vorme van miokloniese toestande multifokale vorme van fokale kortikale ontladings verteenwoordig, is ’n oorvereenvoudiging. 2. Die dissosiasie tussen inisiële en latere komponente van die ontlokte potensiaal is minder robuust as wat algemeen aanvaar word, en subkortikale invoer mag latere komponente van die ontlokte potensiaal beïnvloed. 3. In ’n groot proporsie van gevalle is die latensie van kortikale spits ontlading tot miokloniese ruk, verkry deur “jerk locked averaging”, nie verenigbaar met met ’n kortikale oorsprong vir die spits ontlading nie. 4. Geen bewyse bestaan vir die teorie dat mioklonus ’n vorm van ’n lang latensie refleks is en dat mioklonus ’n refleks is wat ontstaan uit subkliniese sensoriese invoer nie.

Myoclonus-Dystonia (MD) is an inherited, rare, autosomal dominant movement disorder characterized by quick, involuntary muscle jerking or twitching (myoclonus) and involuntary muscle contractions that cause twisting and pulling movements, resulting in abnormal postures (dystonia). The first MD locus was mapped to 7q21-q31 and called DYT11; this locus corresponds to the SGCE gene. Our group previously identified a second MD locus (DYT15) which maps to a 3.18 Mb region on 18p11. Two patients were chosen to undergo next-generation sequencing, which identified 2,292 shared novel variants within the critical region. Analysis of these variants revealed a 3 bp duplication in a transcript referred to as CD108131, which is believed to be a long non-coding RNA. Characterization of this transcript determined that it is 863 bp in size, it is ubiquitously expressed, with high expression in the cerebellum, and it accounts for ~3% of MD cases.