7f57
Kainate-bound GluK2-1xNeto2 complex, at the desensitized state
Structural highlights
FunctionGRIK2_RAT Ionotropic glutamate receptor. L-glutamate acts as an excitatory neurotransmitter at many synapses in the central nervous system. Binding of the excitatory neurotransmitter L-glutamate induces a conformation change, leading to the opening of the cation channel, and thereby converts the chemical signal to an electrical impulse. The receptor then desensitizes rapidly and enters a transient inactive state, characterized by the presence of bound agonist. May be involved in the transmission of light information from the retina to the hypothalamus. Modulates cell surface expression of NETO2 (By similarity).[1] [2] Publication Abstract from PubMedGlutamate-gated kainate receptors are ubiquitous in the central nervous system of vertebrates, mediate synaptic transmission at the postsynapse and modulate transmitter release at the presynapse(1-7). In the brain, the trafficking, gating kinetics and pharmacology of kainate receptors are tightly regulated by neuropilin and tolloid-like (NETO) proteins(8-11). Here we report cryo-electron microscopy structures of homotetrameric GluK2 in complex with NETO2 at inhibited and desensitized states, illustrating variable stoichiometry of GluK2-NETO2 complexes, with one or two NETO2 subunits associating with GluK2. We find that NETO2 accesses only two broad faces of kainate receptors, intermolecularly crosslinking the lower lobe of ATD(A/C), the upper lobe of LBD(B/D) and the lower lobe of LBD(A/C), illustrating how NETO2 regulates receptor-gating kinetics. The transmembrane helix of NETO2 is positioned proximal to the selectivity filter and competes with the amphiphilic H1 helix after M4 for interaction with an intracellular cap domain formed by the M1-M2 linkers of the receptor, revealing how rectification is regulated by NETO2. Kainate receptor modulation by NETO2.,He L, Sun J, Gao Y, Li B, Wang Y, Dong Y, An W, Li H, Yang B, Ge Y, Zhang XC, Shi YS, Zhao Y Nature. 2021 Nov;599(7884):325-329. doi: 10.1038/s41586-021-03936-y. Epub 2021 , Sep 22. PMID:34552241[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||||
