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3hsy
From Proteopedia
High resolution structure of a dimeric GluR2 N-terminal domain (NTD)
Structural highlights
Function[GRIA2_RAT] Receptor for glutamate that functions as ligand-gated ion channel in the central nervous system and plays an important role in excitatory synaptic transmission. 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. In the presence of CACNG4 or CACNG7 or CACNG8, shows resensitization which is characterized by a delayed accumulation of current flux upon continued application of glutamate.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe assembly of AMPA-type glutamate receptors (AMPARs) into distinct ion channel tetramers ultimately governs the nature of information transfer at excitatory synapses. How cells regulate the formation of diverse homo- and heteromeric AMPARs is unknown. Using a sensitive biophysical approach, we show that the extracellular, membrane-distal AMPAR N-terminal domains (NTDs) orchestrate selective routes of heteromeric assembly via a surprisingly wide spectrum of subunit-specific association affinities. Heteromerization is dominant, occurs at the level of the dimer, and results in a preferential incorporation of the functionally critical GluA2 subunit. Using a combination of structure-guided mutagenesis and electrophysiology, we further map evolutionarily variable hotspots in the NTD dimer interface, which modulate heteromerization capacity. This 'flexibility' of the NTD not only explains why heteromers predominate but also how GluA2-lacking, Ca(2+)-permeable homomers could form, which are induced under specific physiological and pathological conditions. Our findings reveal that distinct NTD properties set the stage for the biogenesis of functionally diverse pools of homo- and heteromeric AMPAR tetramers. Subunit-selective N-terminal domain associations organize the formation of AMPA receptor heteromers.,Rossmann M, Sukumaran M, Penn AC, Veprintsev DB, Babu MM, Greger IH EMBO J. 2011 Mar 2;30(5):959-71. Epub 2011 Feb 11. PMID:21317873[15] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Buffalo rat | Large Structures | Greger, I H | Penn, A C | Rossmann, M | Sukumaran, M | Veprintsev, D B | Cell junction | Cell membrane | Endoplasmic reticulum | Glutamate receptor | Glycoprotein | Ion transport | Ionic channel | Ligand-gated ion channel | Lipoprotein | Membrane | Palmitate | Phosphoprotein | Postsynaptic cell membrane | Receptor | Rna editing | Synapse | Transmembrane | Transport | Transport protein
