Protein aggregation and its consequences for human disease.

Protein molecules have emerged through evolution so that they are able to remain in their functional and soluble states under normal physiological conditions, although in other situations they often have a high propensity to aggregate. Aggregation in vivo is associated with a wide range of human disorders, including Alzheimer's disease and type II diabetes, medical conditions that are becoming increasingly common in the modern world. In such diseases, aggregated proteins can often be observed as highly intractable thread-like species known as amyloid fibrils. This article provides an overview of our present knowledge of the nature of these fibrillar aggregates and the manner in which they form, and discusses the origins and potential means of suppression of the pathogenic properties with which they and their precursors are associated.