8ovi

Publication Abstract from PubMed

The complex kinetics of disease-related amyloid aggregation of proteins such as alpha-Synuclein (alpha-Syn) in Parkinson's disease and Abeta42 in Alzheimer's disease include primary nucleation, amyloid fibril elongation and secondary nucleation. The latter can be a key accelerator of the aggregation process. It has been demonstrated that the chaperone domain BRICHOS can interfere with the secondary nucleation process of Abeta42. Here, we explore the mechanism of secondary nucleation inhibition of the BRICHOS domain of the lung surfactant protein (proSP-C) against alpha-Syn aggregation and amyloid formation. We determine the 3D NMR structure of an inactive trimer of proSP-C BRICHOS and its active monomer using a designed mutant. Furthermore, the interaction between the proSP-C BRICHOS chaperone and a substrate peptide has been studied. NMR-based interaction studies of proSP-C BRICHOS with alpha-Syn fibrils show that proSP-C BRICHOS binds to the C-terminal flexible fuzzy coat of the fibrils, which is the secondary nucleation site on the fibrils. Super-resolution fluorescence microscopy demonstrates that proSP-C BRICHOS runs along the fibrillar axis diffusion-dependently sweeping off monomeric alpha-Syn from the fibrils. The observed mechanism explains how a weakly binding chaperone can inhibit the alpha-Syn secondary nucleation pathway via avidity where a single proSP-C BRICHOS molecule is sufficient against up to ~7-40 alpha-Syn molecules embedded within the fibrils.

The inhibitory action of the chaperone BRICHOS against the alpha-Synuclein secondary nucleation pathway.,Ghosh D, Torres F, Schneider MM, Ashkinadze D, Kadavath H, Fleischmann Y, Mergenthal S, Guntert P, Krainer G, Andrzejewska EA, Lin L, Wei J, Klotzsch E, Knowles T, Riek R Nat Commun. 2024 Nov 20;15(1):10038. doi: 10.1038/s41467-024-54212-2. PMID:39567476^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.