R, 2005; Nanao et al., 2005; Naur et al., 2005; Mayer et al., 2006) (Fig. 8B). There are several noteworthy differences among the kainate receptor LBDs, such as the loss of a hydrogen bond to the agonist -amino group at GluK2 Ala487, which is equivalent to Thr480 in GluA2 and Thr503 in GluK1. This may contribute to the higher glutamate EC50 for GluK2 compared with GluK1 (Mayer, 2005). A central fe