Ikeda K, Nagasawa M, Mori H, Araki K, Sakimura K, Watanabe M, Inoue Y, Mishina M
Department of Neuropharmacology, Niigata University, Japan.
FEBS Lett. 1992 Nov 16;313(1):34-8. doi: 10.1016/0014-5793(92)81178-o.
The primary structure of a novel subunit of the mouse NMDA (N-methyl-D-aspartate) receptor channel, designated epsilon 4, has been revealed by cloning and sequencing the cDNA. The epsilon 4 subunit shares high amino acid sequence identity with the epsilon 1, epsilon 2 and epsilon 3 subunits of the mouse NMDA receptor channel, thus constituting the epsilon subfamily of the glutamate receptor channel. Expression from cloned cDNAs of the epsilon 4 subunit together with the zeta 1 subunit in Xenopus oocytes yields functional NMDA receptor channels. The epsilon 4/zeta 1 heteromeric channel exhibits high apparent affinities for agonists and low sensitivities to competitive antagonists. The epsilon 4 subunit is thus distinct in functional properties from the epsilon 1, epsilon 2 and epsilon 3 subunits, and contributes further diversity of the NMDA receptor channel.
