Subcellular localization of α-synuclein in primary neuronal cultures: effect of missense mutations
Numerous recent observations have implicated α-synuclein in the pathogenesis of several neurodegenerative diseases, including Parkinson’s disease, Alzheimer’s disease, dementia with Lewy bodies and multiple-system atrophy. Two missense mutations in the gene for α-synuclein have been identified in some cases of familial Parkinson’s disease and it is thought that these may disrupt the normal structure of the protein and thus promote aggregation into Lewy body filaments. Here, we examine the subcellular localization of α-synuclein in primary cortical neurons maintained in a monolayer culture. The protein has widespread expression throughout neurons, including the nucleus, and has a discete localization in the neurites of more mature neurons, reminiscent of synaptic specializations. Interestingly, in a subpopulation of cortical neurons transfected at 13 days in vitro, we find that α-synuclein appears to aggregate into distinct punctate inclusions in the cytoplasm and proximal neurites. Unlike Lewy bodies, these structures are not ubiquitin positive. These regions of α-synuclein accumulation are observed following transfections with wild-type, Ala30Pro or Ala53Thr α-synuclein; neither mutation alters their frequency.
KeywordsLewy Body Expression Construct Primary Cortical Neuron Discrete Localization Primary Neuronal Culture
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- Engelender S, Guo X, Hoffman B.E. (1998) Synphilin-1: a novel protein that interacts with alpha-synuclein. Soc Neurosci Abstr 24 (Part 1): 968Google Scholar
- Irizarry M.C., Kim T-W, McNamara M, Tanzi R.E., George J.M., Clayton D.F., Hyman B.T. (1996) Characterization of the precursor protein of the non-Ab component of senile plaques (NACP) in the human central nervous system. J Neuropathol Exp Neurol 55:889–895Google Scholar
- Irizarry M.C., Growdon W, Gomez-Isla T, Newell K, George J.M., Clayton D.F., Hyman B.T. (1998) Nigral and corticallewy bodies and dystrophic nigral neurites in Parkinson’s disease and cortical lewy body disease contain α-synuclein immunoreactivity. J Neuropathol Exp Neurol 57: 334–337PubMedCrossRefGoogle Scholar
- Jakes R, Spillantini M.G., Goedert M (1994) Identification of two distinct synucleins from human brain. FEBS Lett 345: 27–32Google Scholar
- Nakajo S, Kawarazaki S, Kanai T, Hirabayashi T, Nakaya K (1998) Analysis of binding proteins for PNP-14 and α-synuclein. Soc N eurosci Abstr 24 (Part 1): 967Google Scholar
- Payton J.E., Perrin R.J., Clayton D.F., George J.M. (1998) Protein-protein interactions of asynuclein. Soc Neurosci Abstr 24 (Part 1): 966Google Scholar
- Polymeropoulos M.H., Lavedan C, Leroy E, Idle S.E., Dehejia A, Dutra A, Pike B, Root H, Rubenstein J, Boyer R, Stenroos E.S., Chandrasekharappa S, Athanassiadou A, Papaetropoulos T, Johnson W.G., Lazzarini A.M., Duvoisin R.C., Iorio G.D., Golbe L.I., Nussbaum R.L. (1997) Mutation in the α-Synuclein gene identified in families with Parkinson’s disease. Science 276: 2045–2047PubMedCrossRefGoogle Scholar