The identification of novel alpha-synuclein-immunoreactive bands in these various forms of parkinsonism may open new research avenues for exploring the relationship between abnormal protein deposition in the brain and one or more neurodegenerative disorders, including the Contursi form of familial parkinsonism.
With the first variant being defined, genetic heterogeneity has become apparent, as in other families parkinsonism was not linked to the 4q-locus and was not associated with the alpha-synuclein mutation (unpublished data).
NACP/alpha-synuclein and tau constitute two distinctive subsets of filaments in the same neuronal inclusions in brains from a family of parkinsonism and dementia with Lewy bodies: double-immunolabeling fluorescence and electron microscopic studies.
These results indicated that the parkinsonism of the Sagamihara family seems not to be due to previously identified point mutations of alpha-synuclein, tau, or UCH-L1, or to exon deletion of parkin.
The fact that Lewy bodies stain strongly with antibodies to asynuclein and that mutations in the alpha-synuclein gene lead to syndromes in which parkinsonism and dementia occur gives us important clues regarding the biologic processes leading to disease.
Furthermore, studies in singly and doubly tg mice have shown that toxic conversion and accumulation can be accelerated by alpha-synuclein mutations associated with familial parkinsonism, by amyloid beta peptide 1-42 (Abeta 1-42), and by oxidative stress.
In this study no one of our 85 patients of Serbian origin with young-onset (</= 45 years) dopa-responsive parkinsonism (YOP), previously proved negative forPARK1 and PARK2 mutations, had either spinocerebellar ataxia type 2 (SCA2) or SCA3 mutation.
However, MnCl(2) resulted in a significantly stronger decreased viability of cells overexpressing alpha-synuclein after 72 h. These findings suggest that manganese may co-operate with alpha-synuclein in triggering neuronal cell death such as seen in manganese parkinsonism.
Mutations in the alpha-synuclein (alpha-syn) gene are responsible for a rare familial parkinsonism syndrome, a finding that has led to extensive characterization of altered alpha-syn structure in sporadic Parkinson's disease (PD) and other neurodegenerative disorders.
We demonstrate dopamine neuron loss and other features of Parkinsonism based on the interaction of several of these human risk factors in transgenic mice expressing human alpha-synuclein.
Recent molecular biology research on neurodegenerative diseases, including parkinsonisms, has identified mutations in the genes that code for the proteins alpha-synuclein and tau, which have been used to classify them into synucleinopathies and tauopathies.
The results indicate that, in this family, where disease is caused by overexpression of normal alpha-synuclein, cardiac sympathetic denervation cosegregates with parkinsonism.
These findings prompted us to screen for multiplication of the SNCA locus in nine families in whom parkinsonism segregates as an autosomal dominant trait.
We examined 7 patients from a family harboring a novel mutation in the alpha-synuclein gene (E46K) that segregated with a phenotype of parkinsonism and dementia with Lewy bodies.