Inhibition of fibril formation and toxicity of a fragment of alpha-synuclein by an N-methylated peptide analogue.

Neurosci Lett

Centre for Peptide and Protein Engineering, School of Biology and Biochemistry, The Queen's University of Belfast, Medical Biology Centre, Belfast BT9 7BL, UK.

Published: April 2004

Alpha-synuclein has been linked to amyloidogenesis in Parkinson's disease and other neurodegenerative disorders. We have previously shown that a peptide comprising residues 68-78 of alpha-synuclein is the minimum fragment that, like alpha-synuclein itself, forms amyloid fibrils and exhibits toxicity towards cells in culture. Hughes et al. [J. Biol. Chem. 275 (2000) 25109] showed that an N-methylated derivative of Abeta(25-35) inhibited the formation of fibrils by Abeta(25-35) and reduced its toxicity. We have now extended this concept to an amyloidogenic alpha-synuclein-based peptide. Alpha-synuclein(68-78), N-methylated at G1y73, was compared to non-methylated peptide. Whereas alpha-synuclein(68-78) formed fibrils and was toxic to cells, the N-methylated analogue had neither of these properties. Moreover, an equimolar mixture of the non-methylated and methylated peptides formed very few fibrils and toxicity was markedly reduced.

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http://dx.doi.org/10.1016/j.neulet.2003.12.077DOI Listing

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