Related Experiment Video
Updated: May 22, 2026

In Vitro SUMOylation Assay to Study SUMO E3 Ligase Activity
Published on: January 29, 2018
Homeostatic synaptic scaling is regulated by protein SUMOylation
Tim J Craig1, Nadia Jaafari, Milos M Petrovic
1Medical Research Council Centre for Synaptic Plasticity, School of Biochemistry, University of Bristol, Bristol BS8 1TD, United Kingdom.
None:
Homeostatic scaling allows neurons to alter synaptic transmission to compensate for changes in network activity. Here, we show that suppression of network activity with tetrodotoxin, which increases surface expression of AMPA receptors (AMPARs), dramatically reduces levels of the deSUMOylating (where SUMO is small ubiquitin-like modifier) enzyme SENP1, leading to a consequent increase in protein SUMOylation. Overexpression of the catalytic domain of SENP1 prevents this scaling effect, and we identify Arc as a SUMO substrate involved in the tetrodotoxin-induced increase in AMPAR surface expression. Thus, protein SUMOylation plays an important and previously unsuspected role in synaptic trafficking of AMPARs that underlies homeostatic scaling.
Related Concept Videos
Integration of Synaptic Events
Chemical Synapses
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Chemical Synapses
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein.
Regulation of Nuclear Protein Sorting

