A method to study human synaptic protein-protein interactions by using flow cytometry coupled to proximity ligation...

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Synapses rely on complex protein-protein interactions (PPIs) for function.
• Mapping synaptic PPIs is key to understanding cognition, plasticity, learning, and memory.
• Analyzing PPIs in living humans is challenging, necessitating methods using isolated synaptosomes.

Purpose of the Study:

• To establish a novel method for detecting synaptic PPIs in human brain samples.
• To validate the new method by analyzing known synaptic interactions.

Main Methods:

• Developed Syn-FlowPLA (Flow Cytometric Proximity Ligation Assay on Synaptosomes).
• Applied Syn-FlowPLA to synaptosomes isolated from frozen human frontal cortex and hippocampus.
• Utilized known synaptic interactions as positive controls and non-interacting proteins as negative controls.

Main Results:

• Successfully detected known post-synaptic interactions (NMDARs-PSD95).
• Successfully detected known pre-synaptic interactions (SNAP25-VAMP2-STX1A).
• Confirmed specificity by analyzing a non-interacting pair (SOD2-PSD95).

Conclusions:

• Syn-FlowPLA enables rapid analysis of synaptic PPIs in isolated synaptosomes from frozen human brain tissue.
• The method offers high target sensitivity for studying human synaptic PPIs.
• Syn-FlowPLA is a valuable tool for investigating synaptic function in both physiological and pathological conditions.