On June 9th, Science published a report from ION entitled “Long-term potentiation of neuron-glia synapses mediated by Ca2+-permeable AMPA receptors”. This work was done by graduate students Wu-ping Ge and Xiu-juan Yang, under the supervision of Dr. Shu-min Duan.

Glial cells in the central nervous system consist of a heterogeneous population of cell types. NG2 cells express the chondriotin sulfate proteoglycan NG2 and have also been described as oligodendrocyte precursor cells (OPCs) or “protoplasmic” astrocytes. Most interestingly, NG2 cells in the CA1 area of the hippocampus receive direct glutamatergic and GABAergic synaptic inputs from neurons. We found that these neuron-glia synapses undergo activity-dependent modification analogous to long-term potentiation (LTP) at excitatory synapses, a hallmark of neuronal plasticity. Thus, although the structure of these synapses found in NG2 cells may differ from that of neuronal synapses, these neuron-NG2 cell synapses have adequate expression and localization of components required for both the induction and expression of LTP. Unlike LTP induced at many neuron-neuronal synapses, however, both induction and expression of neuron-NG2 LTP involve Ca2+-permeable AMPARs on NG2 cells. Rapid neuron-NG2 cell signaling may allow rapid feedback regulation of neuronal functions by Ca2+-dependent secretion of neuroactive factors, and the strength of such feedback regulation will increase following the induction of gLTP. These findings demonstrate a novel form of activity-dependent long-term enhancement of neuron-glia signaling and suggest additional sites for information storage in the brain.