Functional Amyloids As Natural Storage of Peptide Hormones in Pituitary Secretory Granules

Laboratory of Physical Chemistry, Eidgenössische Technische Hochschule (ETH) Zürich, Wolfgang-Paulistrasse 10, CH-8093 Zürich, Switzerland.
Science (Impact Factor: 33.61). 07/2009; 325(5938):328-32. DOI: 10.1126/science.1173155
Source: PubMed


Amyloids are highly organized cross-beta-sheet-rich protein or peptide aggregates that are associated with pathological conditions including Alzheimer's disease and type II diabetes. However, amyloids may also have a normal biological function, as demonstrated by fungal prions, which are involved in prion replication, and the amyloid protein Pmel17, which is involved in mammalian skin pigmentation. We found that peptide and protein hormones in secretory granules of the endocrine system are stored in an amyloid-like cross-beta-sheet-rich conformation. Thus, functional amyloids in the pituitary and other organs can contribute to normal cell and tissue physiology.

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Available from: Michael R Sawaya, Jun 23, 2014
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    • "of biological processes, as diverse as biofilm formation, development of aerial structures, regulation of melanin synthesis, hormone production, epigenetic control of polyamines, and information transfer (Fowler et al., 2007; Maji et al., 2009; Maury, 2009b). In the case of prions, several properties, including transmissibility and species specificity seem to be dependent on the amyloid conformation (Jones and Surewicz, 2005; Toyama and Weissman, 2011; Frederick et al., 2014; Wickner et al., 2014). "
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    • "To probe the amyloidogenicity of the fibril networks, CR and ThT binding studies were performed. Both CR and ThT are known to bind the amyloid form of the protein/peptide aggregates and not to their monomeric counterparts , and were hence used for amyloid detection in vitro and in vivo [36]. ThT generally exhibited an elevated fluorescence signal at 480 nm when bound to amyloid fibrils upon excitation at 450 nm [67]. "
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