科研之友
微信
新浪微博
Facebook
分享链接
摘要
Background. DJ-1, a small ubiquitously expressed protein implicated in several pathways associated with Parkinson's disease pathogenesis, has been found to interact with alpha-synuclein and modulate its aggregation, yet the exact mechanisms remain unclear. Methods: The stability and aggregation properties of wild-type DJ-1 under denaturing conditions, such as low pH, high temperature, presence of denaturants were investigated. The interaction between DJ-1 and alpha-synuclein was tested by SDS-PAGE gel and native gel electrophoresis and by size-exclusion HPLC. Fibrillization was monitored by thioflavin T fluorescence assays and amorphous aggregation was followed by light scattering measurements. The morphology of aggregated species was observed by transmission electron microscopy and atomic force microscopy. Protein secondary structures were characterized by far-UV circular dichroism. Results: DJ-1 fibrillization was first observed at low pH or by adding denaturants. Amorphous aggregates formed at neutral pH, and the aggregation was dramatically accelerated by elevated temperature and the presence of alpha-synuclein. Aggregation of DJ-1 were enhanced by heating and perturbed by the co-occurrence of alpha-synuclein but strong interactions between the two proteins were not found. Conclusions: Varying environmental factors led to different aggregation pathways of DJ-1 although a simulated physiological condition would not lead to fibrillization. DJ-1 co-aggregating with alpha-synuclein may result from weak hydrophobic interaction and DJ-1 exhibited chaperon-like activity in the initial time of alpha-synuclein aggregation at high temperature. General significance: This research on DJ-1 presented its aggregation behavior under denaturing conditions and interaction mechanism with alpha-synuclein that may help to decipher its potential neuroprotective or neurotoxic role in Parkinson's disease.
- 出版日期2017-7
