8.A.47.1.2
Neuropilin and tolloid-like protein 2, Neto2 (Neto-2; Neto 2) or BTCL2, of 525 aas and 2 TMSs, one N-terminal and a second near the C-terminus of the protein (Copits and Swanson 2012). It is an accessory subunit of neuronal kainate-sensitive glutamate receptors, GRIK2 and GRIK3. It increases kainate-receptor channel activity, slowing the decay kinetics of the receptors, without affecting their expression at the cell surface, and increasing the open probability of the receptor channels. It modulates the agonist sensitivity of kainate receptors and slows the decay of kainate receptor-mediated excitatory postsynaptic currents (EPSCs), thus directly influencing synaptic transmission. Neto1 and Neto2 are auxiliary subunits of kainate-type glutamate receptors (KARs) that regulate KAR trafficking and gating (Li et al. 2019). CryoEM structures of homotetrameric GluK2 in complex with NETO2 have been published; NETO2 accesses two broad faces of kainate receptors (He et al. 2021).