Researchers who study the fibrous protein aggregates known as amyloid are beginning to come around to the idea that amyloid’s bad reputation may be unfairly one-sided, because its ruinous role in debilitating and sometimes lethal neurodegenerative disorders such as Parkinson’s and Alzheimer’s diseases is only part of the story. As the study of amyloid structure and function advances and as more organisms that use its biophysical properties to their advantage are identified, the current understanding of amyloid is being re-evaluated to accommodate such nonpathological functions.
Although obtaining high-resolution structural information for amyloid has been challenging due to its insolubility and aggregated nature, electron microscopy and solid-state nuclear magnetic resonance studies are providing a clearer picture of amyloid structures and the physical properties shared by the pathogenic and functional forms.
In response to these developments, in the May 13 issue of the Journal of Biological Chemistry, Frank Shewmaker of the Uniformed Services University of the Health Sciences and Ryan P. McGlinchey and Reed B. Wickner of the National Institute of Diabetes and Digestive and Kidney Diseases tackle the evolving concept of amyloid and review various pathogenic and functional amyloids within the framework of the latest structural models.
“Amyloid’s traditional link to disease has led some to assert that the term ‘amyloidlike’ should be used for proteins that possess the hallmarks of amyloid but are not associated with pathological plaques,” the authors write. “Regardless of localization or functionality, there exists a protein biophysical state that is not limited to disease and more broadly represents a low-energy conformation that is common to many polypeptides.”
The minireview is titled “Structural Insights into Functional and Pathological Amyloid."
Angela Hopp (email@example.com) is managing editor for special projects of the Journal of Biological Chemistry.