The tetraspanin TSPAN5 regulates AMPAR exocytosis by interacting with the AP4 complex

Intracellular trafficking of AMPA receptors is a tightly regulated process which involves several adaptor proteins, and is crucial for the activity of excitatory synapses both in basal conditions and during synaptic plasticity. We found that, in rat hippocampal neurons, an intracellular pool of the tetraspanin TSPAN5 promotes exocytosis of AMPA receptors without affecting their internalisation. TSPAN5 mediates this function by interacting with the adaptor protein complex AP4 and Stargazin and possibly using recycling endosomes as a delivery route. This work highlights TSPAN5 as a new adaptor regulating AMPA receptor trafficking.

Automated summary

In rat hippocampal neurons, the tetraspanin TSPAN5 was found to promote exocytosis of AMPA receptors without affecting their internalisation. This function is mediated by TSPAN5 interacting with the adaptor protein complex AP4 and Stargazin, possibly using recycling endosomes as a delivery route. This study highlights the importance of TSPAN5 as a new adaptor protein regulating AMPA receptor trafficking.