Tubulin seeds α-synuclein fibril formation

Increasing evidence suggests that a-synuclein is a common pathogenic molecule in several neurodegenerative diseases, particularly in Parkinson's disease. To understand alpha-synuclein pathology, we investigated molecules that interact with alpha-synuclein in human and rat brains and identified tubulin as an a-synuclein binding/associated protein. Tubulin co-localized with alpha-synuelein in Lewy bodies and other alpha-synuclein-positive pathological structures. Tubulin initiated and promoted alpha-synuclein fibril formation under physiological conditions in vitro. These findings suggest that an interaction between tubulin and alpha-synuclein might accelerate alpha-synuclein aggregation in diseased brains, leading to the formation of Lewy bodies.