Proteomic Analysis of Activity-Dependent Synaptic Plasticity in Hippocampal Neurons

Following long-term treatment with bicuculline and tetrodotoxin (TTX) aimed at modifying synaptic
activity in cultured neurons, we used a proteomic approach to identify the associated changes in protein
expression. The neurons were left untreated, or treated with bicuculline or TTX, and fractionated by
means of differential detergent extraction, after which the proteins in each fraction were separated by
means of two-dimensional (2D) gel electrophoresis, and 57 proteins of interest were identified by mass
spectrometry. The proteins that showed altered expression and/or post-translational modifications
include proteins or enzymes involved in regulating cell and protein metabolism, the cytoskeleton, or
mitochondrial activity. These results suggest that extensive alterations in neuronal protein expression
take place as a result of increased or decreased synaptic activity.
Keywords: excitatory synapses • phosphorylation • dendritic spines • neuroproteomic analysis • mass spectrometry