%0 Journal Article
%T Plasticity-induced actin polymerization in the dendritic shaft regulates intracellular AMPA receptor trafficking.
%A Wong VC
%A Houlihan PR
%A Liu H
%A Walpita D
%A DeSantis MC
%A Liu Z
%A O'Shea EK
%J Elife
%V 13
%N 0
%D 2024 Aug 15
%M 39146380
%F 8.713
%R 10.7554/eLife.80622
%X AMPA-type receptors (AMPARs) are rapidly inserted into synapses undergoing plasticity to increase synaptic transmission, but it is not fully understood if and how AMPAR-containing vesicles are selectively trafficked to these synapses. Here, we developed a strategy to label AMPAR GluA1 subunits expressed from their endogenous loci in cultured rat hippocampal neurons and characterized the motion of GluA1-containing vesicles using single-particle tracking and mathematical modeling. We find that GluA1-containing vesicles are confined and concentrated near sites of stimulation-induced structural plasticity. We show that confinement is mediated by actin polymerization, which hinders the active transport of GluA1-containing vesicles along the length of the dendritic shaft by modulating the rheological properties of the cytoplasm. Actin polymerization also facilitates myosin-mediated transport of GluA1-containing vesicles to exocytic sites. We conclude that neurons utilize F-actin to increase vesicular GluA1 reservoirs and promote exocytosis proximal to the sites of synaptic activity.