AMPA receptors are the most commonly found neurotransmitter receptors in the nervous system. They mediate fast glutamatergic signaling in many parts of the brain and are thought to coassemble with regulatory proteins, of which the TARP (transmembrane AMPA receptor regulatory protein) family is perhaps best known. Using proteomic analysis, immunohistochemistry, and electrophysiology of native AMPA receptors from rat and mouse brain, Schwenk et al. (see the Perspective by Tigaret and Choquet) found that two members of the cornichon family, CNIH-2 and CNIH-3, tightly coassembled with the pore-forming subunits of the AMPA receptors. Indeed, about 70% of the AMPA receptor complexes in the mammalian brain assemble with the cornichon proteins, which promote surface expression of the AMPA receptor complexes and modulate their gating kinetics.
J. Schwenk, N. Harmel, G. Zolles, W. Bildl, A. Kulik, B. Heimrich, O. Chisaka, P. Jonas, U. Schulte, B. Fakler, N. Klöcker, Functional proteomics identify cornichon proteins as auxiliary subunits of AMPA receptors. Science 323, 1313–1319 (2009). [Abstract] [Full Text]