Amyloid β42 (Aβ42) aggregation plays a key role in the pathogenesis of Alzheimer's disease. However, the morphology and structural dynamics in different stages of Aβ42 assembly are not well known. To investigate...Amyloid β42 (Aβ42) aggregation plays a key role in the pathogenesis of Alzheimer's disease. However, the morphology and structural dynamics in different stages of Aβ42 assembly are not well known. To investigate the dynamic properties of morphological and structural changes in the aggregation process of Aβ in vitro, transmission electron microscopy, western blot analysis and circular dichroism were used to observe the changes in morphology, immunoreactivity and secondary structure during Aβ aggregation, respectively. Results demonstrated that at 24 hours following Aβ42 aggregation in vitro, the structures of spherical granules from 5 to 10 nm and coils from 20 to 30 nm were visualized by transmission electron microscopy. Different immunoreactivities of the oligomers and fibers were detected by western blot analysis. The dynamic changes of the α-helix to β-sheet were confirmed by circular dichroism spectra. The dynamic properties of the morphological and structural changes in the aggregation process of Aβ42 in vitro were analyzed, which contributed to the identification of stable conditions of Aβ42 oligomer formation.展开更多
基金Supported by the State Plan for High-Tech Research and Development (863 Project), No. 2006AA02A247the Scientific and Technological Major Special Project of China, No. 2009ZX10004-216Fundamental Research Funds for the Central Universities, No. 2011JBM124
文摘Amyloid β42 (Aβ42) aggregation plays a key role in the pathogenesis of Alzheimer's disease. However, the morphology and structural dynamics in different stages of Aβ42 assembly are not well known. To investigate the dynamic properties of morphological and structural changes in the aggregation process of Aβ in vitro, transmission electron microscopy, western blot analysis and circular dichroism were used to observe the changes in morphology, immunoreactivity and secondary structure during Aβ aggregation, respectively. Results demonstrated that at 24 hours following Aβ42 aggregation in vitro, the structures of spherical granules from 5 to 10 nm and coils from 20 to 30 nm were visualized by transmission electron microscopy. Different immunoreactivities of the oligomers and fibers were detected by western blot analysis. The dynamic changes of the α-helix to β-sheet were confirmed by circular dichroism spectra. The dynamic properties of the morphological and structural changes in the aggregation process of Aβ42 in vitro were analyzed, which contributed to the identification of stable conditions of Aβ42 oligomer formation.