Conselho Nacional de Desenvolvimento Científico e Tecnológico / A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais frequente no mundo, afetando 1-2% da população acima de 65 anos, caracterizada clinicamente por tremor em repouso, bradicinesia, instabilidade postural e rigidez muscular. Essas manifestações surgem devido à degeneração neuronal progressiva e à presença de inclusões proteicas ricas em &#945;-sinucleína. A DP é decorrente da interação entre fatores ambientais e genéticos, e entre os fatores genéticos, variantes exônicas de transmissão dominante nos genes LRRK2 (leucine-rich repeat kinase 2), VPS35 (vacuolar protein sorting 35) e EIF4G1 (eukaryotic translation initiation factor 4-gamma 1) têm sido associadas à etiologia da doença. Entretanto, estudos sobre o efeito dessas variantes na população brasileira são raros ou inexistentes. Por essa razão, neste trabalho rastreamos mutações nos genes VPS35 (p.D620N; p.R524W), EIF4G1 (p.R1205H; p.A502V) e LRRK2 (p.G2019S) em uma amostra de 582 pacientes brasileiros com DP não aparentados e 329 indivíduos controles saudáveis. Além disso, conduzimos o primeiro estudo caso-controle para análise de variantes exônicas raras (p.Q1111H, p.T1410M, p.M1646T, p.S1761R, p.Y2189C) e comuns (p.N551K, p.R1398H, p.K1423K) no gene LRRK2 em um subgrupo de 329 pacientes brasileiros com DP, não aparentados, naturais da região sudeste. Esse subgrupo foi analisado e comparado com 222 indivíduos controles saudáveis a fim de verificar associações dessas variantes e a DP. Em relação às mutações dos genes VPS35 e EIF4G1, não foram encontradas alterações nos pacientes com DP. A mutação p.G2019S no gene LRRK2 foi encontrada em 15 probandos (2,6%), dos quais 9 são do sexo feminino (64,3%). O tremor em repouso foi observado em 47,36% dos pacientes com a mutação p.G2019S como primeiro sintoma motor. As análises das variantes raras no gene LRRK2 não revelaram qualquer associação estatisticamente significante. Entre as variantes comuns, a p.K1423K mostrou evidência de associação de risco com a DP (p<0,05) na estratificação contendo o grupo de indivíduos com história familiar da doença e para as variantes p.N551K e p.R1398H não foram observadas associações. A análise do haplótipo p.N551K-p.R1398H-p.K1423K revelou associação de proteção na amostra sudeste e na estratificação Rio de Janeiro (p<0,05). Esse haplótipo não está em desequilíbrio de ligação na amostra de 222 indivíduos controles brasileiros analisados (r2&#8804;45). Os resultados obtidos neste estudo representam contribuições valiosas ao entendimento da relação entre as variantes genéticas estudadas e o risco de desenvolvimento da doença de Parkinson, principalmente no que se refere aos endofenótipos associados. / Parkinsons disease (PD) is the second most common neurodegenerative disorder in the world, affecting 1-2% of population more than 65 years of age, clinically recognized by resting tremor, bradykinesia, postural instability and rigidity. These manifestations occur due to progressive neuronal degeneration and to the presence of protein inclusions enriched with &#945;-synuclein. PD results from the interaction between environmental and genetic factors, and, among genetic factors, dominant exonic variants in LRRK2 (leucine-rich repeat kinase 2), VPS35 (vacuolar protein sorting 35) e EIF4G1 (eukaryotic translation initiation factor 4-gamma 1) genes have been described as causes of the disease. However, studies of the effect of these variants in Brazilian population are rare or do not exist. For this reason, in this study we decided screening mutations in VPS35 (p.D620N; p.R524W), EIF4G1 (p.R1205H; p.A502V) and LRRK2 (p.G2019S) genes in a cohort of 582 unrelated Brazilian patients with PD and 329 healthy individuals control. In additional, we carried on the first case-control study to analyze LRRK2 exonic rare (p.Q1111H, p.T1410M, p.M1646T, p.S1761R, p.Y2189C) and common (p.N551K, p.R1398H, p.K1423K) variants in a subgroup of 329 unrelated Brazilian patients with PD from Southeastern region. This group was analyzed and compared to 222 healthy individuals control in order to verify associations between these variants and PD. Regarding mutations of VPS35 and EIF4G1 genes, we have not found any alteration in Brazilian patients with PD. The mutation p.G2019S in LRRK2 gene was found in 15 probands (2.6%), 9 of them are female (64,3%). Resting tremor was observed in 47,36% of p.G2019S patients as the predominant initial symptom. Regarding the LRRK2 rare variants, the results showed no significant association. Among LRRK2 common variants, the p.K1423K showed evidence of risk association with PD (p<0,05) in the stratified analysis concerning the group of patients with family history of the disease, in contrast, p.N551K and p.R1398H variants showed no associations. The analysis of p.N551K-p.R1398H-p.K1423K revealed protection in Southeastern group and Rio de Janeiro stratification (p<0,05). This haplotype is not in disequilibrium linkage in 222 Brazilian healthy individuals control analyzed (r2&#8804;45). Results obtained in this research represent valuable contributions for the understanding of association between the genetic variants studied and the risk of developing PD, particularly with regard to the associated endophenotypes.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / A doença de Parkinson (DP) é a segunda doença neurodegenerativa mais frequente no mundo, afetando 1-2% da população acima de 65 anos, caracterizada clinicamente por tremor em repouso, bradicinesia, instabilidade postural e rigidez muscular. Essas manifestações surgem devido à degeneração neuronal progressiva e à presença de inclusões proteicas ricas em &#945;-sinucleína. A DP é decorrente da interação entre fatores ambientais e genéticos, e entre os fatores genéticos, variantes exônicas de transmissão dominante nos genes LRRK2 (leucine-rich repeat kinase 2), VPS35 (vacuolar protein sorting 35) e EIF4G1 (eukaryotic translation initiation factor 4-gamma 1) têm sido associadas à etiologia da doença. Entretanto, estudos sobre o efeito dessas variantes na população brasileira são raros ou inexistentes. Por essa razão, neste trabalho rastreamos mutações nos genes VPS35 (p.D620N; p.R524W), EIF4G1 (p.R1205H; p.A502V) e LRRK2 (p.G2019S) em uma amostra de 582 pacientes brasileiros com DP não aparentados e 329 indivíduos controles saudáveis. Além disso, conduzimos o primeiro estudo caso-controle para análise de variantes exônicas raras (p.Q1111H, p.T1410M, p.M1646T, p.S1761R, p.Y2189C) e comuns (p.N551K, p.R1398H, p.K1423K) no gene LRRK2 em um subgrupo de 329 pacientes brasileiros com DP, não aparentados, naturais da região sudeste. Esse subgrupo foi analisado e comparado com 222 indivíduos controles saudáveis a fim de verificar associações dessas variantes e a DP. Em relação às mutações dos genes VPS35 e EIF4G1, não foram encontradas alterações nos pacientes com DP. A mutação p.G2019S no gene LRRK2 foi encontrada em 15 probandos (2,6%), dos quais 9 são do sexo feminino (64,3%). O tremor em repouso foi observado em 47,36% dos pacientes com a mutação p.G2019S como primeiro sintoma motor. As análises das variantes raras no gene LRRK2 não revelaram qualquer associação estatisticamente significante. Entre as variantes comuns, a p.K1423K mostrou evidência de associação de risco com a DP (p<0,05) na estratificação contendo o grupo de indivíduos com história familiar da doença e para as variantes p.N551K e p.R1398H não foram observadas associações. A análise do haplótipo p.N551K-p.R1398H-p.K1423K revelou associação de proteção na amostra sudeste e na estratificação Rio de Janeiro (p<0,05). Esse haplótipo não está em desequilíbrio de ligação na amostra de 222 indivíduos controles brasileiros analisados (r2&#8804;45). Os resultados obtidos neste estudo representam contribuições valiosas ao entendimento da relação entre as variantes genéticas estudadas e o risco de desenvolvimento da doença de Parkinson, principalmente no que se refere aos endofenótipos associados. / Parkinsons disease (PD) is the second most common neurodegenerative disorder in the world, affecting 1-2% of population more than 65 years of age, clinically recognized by resting tremor, bradykinesia, postural instability and rigidity. These manifestations occur due to progressive neuronal degeneration and to the presence of protein inclusions enriched with &#945;-synuclein. PD results from the interaction between environmental and genetic factors, and, among genetic factors, dominant exonic variants in LRRK2 (leucine-rich repeat kinase 2), VPS35 (vacuolar protein sorting 35) e EIF4G1 (eukaryotic translation initiation factor 4-gamma 1) genes have been described as causes of the disease. However, studies of the effect of these variants in Brazilian population are rare or do not exist. For this reason, in this study we decided screening mutations in VPS35 (p.D620N; p.R524W), EIF4G1 (p.R1205H; p.A502V) and LRRK2 (p.G2019S) genes in a cohort of 582 unrelated Brazilian patients with PD and 329 healthy individuals control. In additional, we carried on the first case-control study to analyze LRRK2 exonic rare (p.Q1111H, p.T1410M, p.M1646T, p.S1761R, p.Y2189C) and common (p.N551K, p.R1398H, p.K1423K) variants in a subgroup of 329 unrelated Brazilian patients with PD from Southeastern region. This group was analyzed and compared to 222 healthy individuals control in order to verify associations between these variants and PD. Regarding mutations of VPS35 and EIF4G1 genes, we have not found any alteration in Brazilian patients with PD. The mutation p.G2019S in LRRK2 gene was found in 15 probands (2.6%), 9 of them are female (64,3%). Resting tremor was observed in 47,36% of p.G2019S patients as the predominant initial symptom. Regarding the LRRK2 rare variants, the results showed no significant association. Among LRRK2 common variants, the p.K1423K showed evidence of risk association with PD (p<0,05) in the stratified analysis concerning the group of patients with family history of the disease, in contrast, p.N551K and p.R1398H variants showed no associations. The analysis of p.N551K-p.R1398H-p.K1423K revealed protection in Southeastern group and Rio de Janeiro stratification (p<0,05). This haplotype is not in disequilibrium linkage in 222 Brazilian healthy individuals control analyzed (r2&#8804;45). Results obtained in this research represent valuable contributions for the understanding of association between the genetic variants studied and the risk of developing PD, particularly with regard to the associated endophenotypes.

京都大学 / 0048 / 新制・課程博士 / 博士(生命科学) / 甲第20820号 / 生博第389号 / 新制||生||51(附属図書館) / 京都大学大学院生命科学研究科高次生命科学専攻 / (主査)教授 米原 伸, 教授 垣塚 彰, 教授 HEJNA James / 学位規則第4条第1項該当 / Doctor of Philosophy in Life Sciences / Kyoto University / DFAM

No description available.

Mitochondria are dynamic; they alter their shape through fission, fusion and budding of vesicles. Mitochondrial vesicles serve as a quality control mechanism enabling these organelles to rid themselves of damaged lipids and proteins. Dysregulation in mitochondrial dynamics and quality control have been linked to Parkinson’s Disease, making the identification of molecules requisite for these processes a priority. We identified the endocytic protein, Sorting nexin 9 (Snx9) through a genome wide siRNA screen for genes which substantially alter mitochondrial morphology and therefore are important for its maintenance. In this work, the role of Snx9 in mitochondrial morphology is examined. Ultrastructural imaging of mitochondria within cells silenced for Snx9 revealed unbudded vesicles along a hyperfused mitochondrial reticulum suggesting a role for Snx9 in the release of these vesicles. The vesicular profiles contained concentric membranous whorls enriched for neutral lipids. Localization studies suggest the Parkinson’s disease genes, Parkin and Vps35 localize to the unbudded profiles.

Mitochondria are dynamic; they alter their shape through fission, fusion and budding of vesicles. Mitochondrial vesicles serve as a quality control mechanism enabling these organelles to rid themselves of damaged lipids and proteins. Dysregulation in mitochondrial dynamics and quality control have been linked to Parkinson’s Disease, making the identification of molecules requisite for these processes a priority. We identified the endocytic protein, Sorting nexin 9 (Snx9) through a genome wide siRNA screen for genes which substantially alter mitochondrial morphology and therefore are important for its maintenance. In this work, the role of Snx9 in mitochondrial morphology is examined. Ultrastructural imaging of mitochondria within cells silenced for Snx9 revealed unbudded vesicles along a hyperfused mitochondrial reticulum suggesting a role for Snx9 in the release of these vesicles. The vesicular profiles contained concentric membranous whorls enriched for neutral lipids. Localization studies suggest the Parkinson’s disease genes, Parkin and Vps35 localize to the unbudded profiles.

Mitochondria are dynamic; they alter their shape through fission, fusion and budding of vesicles. Mitochondrial vesicles serve as a quality control mechanism enabling these organelles to rid themselves of damaged lipids and proteins. Dysregulation in mitochondrial dynamics and quality control have been linked to Parkinson’s Disease, making the identification of molecules requisite for these processes a priority. We identified the endocytic protein, Sorting nexin 9 (Snx9) through a genome wide siRNA screen for genes which substantially alter mitochondrial morphology and therefore are important for its maintenance. In this work, the role of Snx9 in mitochondrial morphology is examined. Ultrastructural imaging of mitochondria within cells silenced for Snx9 revealed unbudded vesicles along a hyperfused mitochondrial reticulum suggesting a role for Snx9 in the release of these vesicles. The vesicular profiles contained concentric membranous whorls enriched for neutral lipids. Localization studies suggest the Parkinson’s disease genes, Parkin and Vps35 localize to the unbudded profiles.