@article {69840,
	title = {EPSILON: a method for pulse-chase labeling to probe synaptic AMPAR exocytosis during memory formation.},
	journal = {Nat Neurosci},
	year = {2025},
	month = {2025 Mar 31},
	abstract = {<p>A tool to map changes in synaptic strength during a defined time window could provide powerful insights into the mechanisms of learning and memory. Here we developed a technique, Extracellular Protein Surface Labeling in Neurons (EPSILON), to map α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) exocytosis in vivo by sequential pulse-chase labeling of surface AMPARs with membrane-impermeable dyes. This approach yields synaptic-resolution maps of AMPAR exocytosis, a proxy for synaptic potentiation, in genetically targeted neurons during memory formation. In mice undergoing contextual fear conditioning, we investigated the relationship between synapse-level AMPAR exocytosis in CA1 pyramidal neurons and cell-level expression of the immediate early gene product cFos, a frequently used marker of engram neurons. We observed a strong correlation between AMPAR exocytosis and cFos expression, suggesting a synaptic mechanism for the association of cFos expression with memory engrams. The EPSILON technique is a useful tool for mapping synaptic plasticity and may be extended to investigate trafficking of other transmembrane proteins.</p>
},
	issn = {1546-1726},
	doi = {10.1038/s41593-025-01922-5},
	url = {https://doi.org/10.1038/s41593-025-01922-5},
	author = {Kim, Doyeon and Park, Pojeong and Li, Xiuyuan and Wong-Campos, J David and Tian, He and Moult, Eric M and Grimm, Jonathan B and Lavis, Luke D and Cohen, Adam E}
}
