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bioRxiv · 10.1101/417873

Intrinsically aggregation-prone proteins form amyloid-like aggregates and contribute to tissue aging in C. elegans

Abstract

Reduced protein homeostasis and increased protein instability is a common feature of aging. Yet it remains unclear whether protein instability is a cause of aging. In neurodegenerative diseases and amyloidoses, specific proteins self-assemble into amyloid fibrils and accumulate as pathological solid aggregates in a variety of tissues. More recently, widespread protein aggregation has been described during normal aging, in the absence of disease processes. Until now, an extensive characterization of the nature of age-dependent protein aggregation and its consequences for aging has been lacking. Here, we show that age-dependent aggregates are rapidly formed by newly synthesized proteins and contain amyloid-like structures similar to disease-associated protein aggregates. Moreover, we demonstrate that age-dependent protein aggregation accelerates the functional decline of different tissues in C. elegans. Together, these finding reveal that the formation of amyloid aggregates is a generic problem of aging and likely to be an important target for strategies designed to maintain physiological functions in later stages of life.

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BibTeXRIS

Huang, C., Wagner-Valladolid, S., Stephens, A. D., Jung, R., Poudel, C., Sinnige, T., Lechler, M. C., Schlörit, N., Laine, R. F., Michel, C. H., Vendruscolo, M. M., Kaminski, C. F., Kaminski Schierle, G. S., David, D. C.. 2018-09-14. Intrinsically aggregation-prone proteins form amyloid-like aggregates and contribute to tissue aging in C. elegans. https://doi.org/10.1101/417873

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