Activation of Na-permeable kainate receptors

Kainate receptors that are formed by subunits GRIK1 and or GRIK2 that are edited at the Q/R and other editing sites in GRIK2 are Ca2+ impermeable. They permit the passage of Na+ ions. Glutamine in GRIK1 at position 636 is replaced by arginine by an editing step which occurs posttranscriptioanlly. GRIK2 is glutamine 621 is edited to arginine. GRIK2 is also edited at 571 (Y/C) where a tyrosine residue is changed to cysteine and 567 (I/V) where an isoleucine is changed to valine. All three sites are edited postranscriptionally. A fully edited GRIK2 at all three sites is impermeable to calcium ions.

由亚基 GRIK1 和或 GRIK2 形成的 Kainate 受体，在 GRIK2 的 Q/R 及其他编辑位点进行编辑，对 Ca2+ 离子具有不可渗透性。它们允许 Na+ 离子的通过。在 GRIK1 的 636 位点上，谷氨酰胺被编辑为精氨酸，这一编辑步骤发生在转录后。GRIK2 中的谷氨酰胺 621 位点被编辑为精氨酸。GRIK2 还在 571 位点（Y/C）进行编辑，其中酪氨酸残基被半胱氨酸所取代，以及 567 位点（I/V），其中异亮氨酸被缬氨酸所替换。这三个位点均发生转录后编辑。在所有三个位点均完全编辑的 GRIK2 对钙离子具有不可渗透性。