| First Author | Antion MD | Year | 2010 |
| Journal | Mol Cell Neurosci | Volume | 45 |
| Issue | 4 | Pages | 378-88 |
| PubMed ID | 20678574 | Mgi Jnum | J:171314 |
| Mgi Id | MGI:4949591 | Doi | 10.1016/j.mcn.2010.07.011 |
| Citation | Antion MD, et al. (2010) Ephrin-B3 regulates glutamate receptor signaling at hippocampal synapses. Mol Cell Neurosci 45(4):378-88 |
| abstractText | B-ephrin-EphB receptor signaling modulates NMDA receptors by inducing tyrosine phosphorylation of NR2 subunits. Ephrins and EphB RTKs are localized to postsynaptic compartments in the CA1, and therefore potentially interact in a non-canonical cis- configuration. However, it is not known whether cis- configured receptor-ligand signaling is utilized by this class of RTKs, and whether this might influence excitatory synapses. We found that ablation of ephrin-B3 results in an enhancement of the NMDA receptor component of synaptic transmission relative to the AMPA receptor component in CA1 synapses. Synaptic AMPA receptor expression is reduced in ephrin-B3 knockout mice, and there is a marked enhancement of tyrosine phosphorylation of the NR2B receptor subunit. In a reduced system co-expression of ephrin-B3 attenuated EphB2-mediated NR2B tyrosine phosphorylation. Moreover, phosphorylation of EphB2 was elevated in the hippocampus of ephrin-B3 knockout mice, suggesting that regulation of EphB2 activity is lost in these mice. Direct activation of EphB RTKs resulted in phosphorylation of NR2B and a potential signaling partner, the non-receptor tyrosine kinase Pyk2. Our data suggests that ephrin-B3 limits EphB RTK-mediated phosphorylation of the NR2B subunit through an inhibitory cis- interaction which is required for the correct function of glutamatergic CA1 synapses. |
