Ast A, Buntru A, Schindler F, Hasenkopf R, Schulz A, Brusendorf L, Klockmeier K, Grelle G, McMahon B, Niederlechner H, Jansen I, Diez L, Edel J, Boeddrich A, Franklin SA, Baldo B, Schnoegl S, Kunz S, Purfürst B, Gaertner A, Kampinga HH, Morton AJ, Petersén Å, Kirstein J, Bates GP, Wanker EE. mHTT Seeding Activity: A Marker of Disease Progression and Neurotoxicity in Models of Huntington's Disease. Mol Cell. 2018 Sep 6;71(5):675-688.e6. PMID: 30193095.
From the abstract: "Self-propagating, amyloidogenic mutant huntingtin (mHTT) aggregates may drive progression of Huntington's disease (HD). Here, we report the development of a FRET-based mHTT aggregate seeding (FRASE) assay that enables the quantification of mHTT seeding activity (HSA) ... Application of the FRASE assay revealed HSA in brain homogenates of presymptomatic HD transgenic and knockin mice and its progressive increase with phenotypic changes, suggesting that HSA quantitatively tracks disease progression. Biochemical investigations ... demonstrated that small, rather than large, mHTT structures are responsible for the HSA measured in FRASE assays. Finally, we assessed the neurotoxicity of mHTT seeds in an inducible Drosophila model transgenic for HTTex1. We found a strong correlation between the HSA measured in adult neurons and the increased mortality of transgenic HD flies, indicating that FRASE assays detect disease-relevant, neurotoxic, mHTT structures with severe phenotypic consequences in vivo."