Referenced in: none

Automatically associated channels: Kir2.3

Title: Masking of the endoplasmic reticulum retention signals during assembly of the NMDA receptor.

Authors: Martin Horak, Kai Chang, Robert J Wenthold

Journal, date & volume: J. Neurosci., 2008 Mar 26 , 28, 3500-9

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/18367616

Abstract
NMDA receptors are glutamate-gated ion channels that play important roles in synaptic transmission and excitotoxicity. The functional NMDA receptor is thought to be a heterotetramer composed mainly of two NR1 and two NR2 subunits. Although it is generally accepted that only correctly assembled NMDA receptors can pass the ER quality control, the mechanism underlying this process is not well understood. Using truncated and chimeric NMDA receptor subunits expressed in heterologous cells and cortical neurons, we found that the third membrane domains (M3) of both NR1 and NR2B contain signals that cause the unassembled subunits to be retained in the ER. M3 of both NR1 and NR2B and, M4 of NR1, are necessary for masking ER retention signals found in M3. Thus, our data reveal a critical role of the membrane domains in the assembly of functional NMDA receptors.