title: Intracellular screening of a peptide library to derive a potent peptide inhibitor of α-synuclein aggregation.
abstract: Aggregation of α-synuclein (α-syn) into toxic fibrils is a pathogenic hallmark of Parkinson disease (PD). Studies have focused largely on residues 71-82, yet most early-onset mutations are located between residues 46 and 53. A semirationally designed 209,952-member library based entirely on this region was constructed, containing all wild-type residues and changes associated with early-onset PD. Intracellular cell survival screening and growth competition isolated a 10-residue peptide antagonist that potently inhibits α-syn aggregation and associated toxicity at a 1:1 stoichiometry. This was verified using continuous growth measurements and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cytotoxicity studies. Atomic force microscopy and circular dichroism on the same samples showed a random-coil structure and no oligomers. A new region of α-syn for inhibitor targeting has been highlighted, together with the approach of using a semirational design and intracellular screening. The peptides can then be used as candidates for modification in drugs capable of slowing or even preventing the onset of PD.
authors.affiliation: From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ.
authors.forename: Harish
authors.initials: H
authors.lastname: Cheruvara
authors.affiliation: From the School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, Essex CO4 3SQ.
authors.forename: Victoria L
authors.initials: VL
authors.lastname: Allen-Baume
authors.affiliation: the School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, and.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Kad
authors.affiliation: the Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom j.mason@bath.ac.uk.
authors.forename: Jody M
authors.initials: JM
authors.lastname: Mason
mesh_terms: D000544:Alzheimer Disease / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D002942:Circular Dichroism; D017931:DNA Primers; D016631:Lewy Bodies / Q000378:metabolism; D018625:Microscopy, Atomic Force; D010300:Parkinson Disease / Q000378:metabolism; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D051844:alpha-Synuclein / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D017931:DNA Primers; D019151:Peptide Library; D010455:Peptides; D051844:alpha-Synuclein
keywords: Alpha-synuclein (α-Synuclein); Amyloid; Library Screening; Parkinson Disease; Protein Misfolding; Protein-Fragment Complementation Assay; Protein-Protein Interaction