Amyloids are fibrous cross-β protein aggregates that are capable of proliferation via nucleated polymerization. Amyloid conformation likely represents an ancient protein fold and is linked to various biological or pathological manifestations. Self-perpetuating amyloid-based protein conformers provide a molecular basis for transmissible (infectious or heritable) protein isoforms, termed prions. Amyloids and prions, as well as other types of misfolded aggregated proteins are associated with a variety of devastating mammalian and human diseases, such as Alzheimer's, Parkinson's and Huntington's diseases, transmissible spongiform encephalopathies (TSEs), amyotrophic lateral sclerosis (ALS) and transthyretinopathies. In yeast and fungi, amyloid-based prions control phenotypically detectable heritable traits. Simplicity of cultivation requirements and availability of powerful genetic approaches makes yeast Saccharomyces cerevisiae an excellent model system for studying molecular and cellular mechanisms governing amyloid formation and propagation. Genetic techniques allowing for the expression of mammalian or human amyloidogenic and prionogenic proteins in yeast enable researchers to capitalize on yeast advantages for characterization of the properties of disease-related proteins. Chimeric constructs employing mammalian and human aggregation-prone proteins or domains, fused to fluorophores or to endogenous yeast proteins allow for cytological or phenotypic detection of disease-related protein aggregation in yeast cells. Yeast systems are amenable to high-throughput screening for antagonists of amyloid formation, propagation and/or toxicity. This review summarizes up to date achievements of yeast assays in application to studying mammalian and human disease-related aggregating proteins, and discusses both limitations and further perspectives of yeast-based strategies.
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Nanopore‐Based, Rapid Characterization of Individual Amyloid Particles in Solution: Concepts, Challenges, and Prospects
Aggregates of misfolded proteins are associated with several devastating neurodegenerative diseases. These so‐called amyloids are therefore explored as biomarkers for the diagnosis of dementia and other disorders, as well as for monitoring disease progression and assessment of the efficacy of therapeutic interventions. Quantification and characterization of amyloids as biomarkers is particularly demanding because the same amyloid‐forming protein can exist in different states of assembly, ranging from nanometer‐sized monomers to micrometer‐long fibrils that interchange dynamically both in vivo and in samples from body fluids ex vivo. Soluble oligomeric amyloid aggregates, in particular, are associated with neurotoxic effects, and their molecular organization, size, and shape appear to determine their toxicity. This concept article proposes that the emerging field of nanopore‐based analytics on a single molecule and single aggregate level holds the potential to account for the heterogeneity of amyloid samples and to characterize these particles—rapidly, label‐free, and in aqueous solution—with regard to their size, shape, and abundance. The article describes the concept of nanopore‐based resistive pulse sensing, reviews previous work in amyloid analysis, and discusses limitations and challenges that will need to be overcome to realize the full potential of amyloid characterization on a single‐particle level.
more » « less- NSF-PAR ID:
- 10075723
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 14
- Issue:
- 46
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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