ESCRT-0 regulates AMPA receptor conductance and Ca2+- dependent signaling

ABSTRACT: Membrane protein trafficking is essential for synaptic growth, maintenance, function, and plasticity and involves the regulated exocytosis and endocytosis of proteins to and from the pre- and post-synaptic membranes. Defects in membrane protein trafficking can lead to the accumulation of ubiquitinated membrane proteins and contribute to neurodegenerative disease. The ESCRT (endosomal sorting complexes required for transport) machinery binds and sorts ubiquitinated membrane proteins into lysosomes for degradation, yet the presence and function of ESCRTs in sorting ubiquitinated AMPA and other receptors at the post-synapse remain unclear. Here we show that the ubiquitin-binding ESCRT-0 protein, Hrs, localizes to both pre- and post-synapses, and levels are modulated by neuronal activity, increasing and decreasing with higher and lower neuronal activity, respectively. Phosphoproteomic profiling of Hrs-depleted post-synaptic membranes revealed a role for Hrs in glutamatergic synaptic transmission, including long-term potentiation. In addition, Hrs-depleted neurons showed faster AMPAR current kinetics and reduced amplitude in whole-cell patch-clamp recordings. Furthermore, genetic deletion of neuronal Hgs in mice led to reductions in phosphorylated CaMKII-alpha and -beta (T286/T287) and in the structural proteins, PSD-95 and gephyrin, suggestive of long-term depression (LTD)-like synaptic depression. Hrs overexpression led to increased Ca2+-responsive signaling, including phosphorylation of protein kinase C (PKC) substrates and AMPAR subunit GluA1-S831, which increases conductance. Together these findings identify a dynamic, bidirectional role for Hrs at the post-synapse as it both senses and is modulated by neuronal activity, ultimately impacting excitatory synaptic strength

INSTRUMENT(S): Orbitrap Eclipse

ORGANISM(S): Mus Musculus (ncbitaxon:10090)

SUBMITTER: Christina Sigurdson  

PROVIDER: MSV000100622 | MassIVE | Wed Jan 28 08:19:00 GMT 2026

SECONDARY ACCESSION(S): PXD073715

REPOSITORIES: MassIVE