SynPull: An advanced method for studying neurodegeneration-related aggregates in synaptosomes using super-resolution...

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Synaptic dysfunction is a key feature of Alzheimer's and Parkinson's diseases, impacting cognition.
• Pathological aggregation of alpha-synuclein, beta-amyloid, and tau proteins contributes to synaptopathology.
• Current methods for studying small, soluble protein aggregates in synapses are limited.

Purpose of the Study:

• To introduce SynPull, a novel method for characterizing protein aggregates within synaptosomes.
• To investigate the types and sizes of protein aggregates in human and mouse synaptosomes from neurodegenerative diseases.
• To elucidate the role of specific protein aggregates in synaptic dysfunction.

Main Methods:

• SynPull combines single-molecule pull-down, super-resolution microscopy, and computational analysis.
• Analysis of protein aggregates in synaptosomes from postmortem Alzheimer's disease and control brains.
• Comparison of intra-synaptic aggregates with extra-synaptic aggregates.

Main Results:

• AT8-positive tau aggregates were the predominant type in Alzheimer's disease synaptosomes.
• Aggregate size did not significantly change with disease progression in synaptosomes.
• Alpha-synuclein and beta-amyloid aggregates in synapses were larger than their extra-synaptic counterparts.

Conclusions:

• SynPull is a valuable tool for studying pathological protein aggregates in neurodegenerative diseases.
• The findings provide insights into the specific aggregates driving synaptic dysfunction in Alzheimer's disease.
• Understanding aggregate characteristics can elucidate disease mechanisms and inform therapeutic strategies.