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Updated: Aug 17, 2026

Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
Nogo-A interacts with the Nogo-66 receptor through multiple sites to create an isoform-selective subnanomolar agonist
Fenghua Hu1, Betty P Liu, Stephane Budel
1Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
Abstract:
Nogo is a myelin-derived protein that limits axonal regeneration after CNS injury. A short hydrophilic Nogo-66 loop between two hydrophobic domains of Nogo binds to a Nogo-66 receptor (NgR) to inhibit axonal outgrowth. Inhibition of axon outgrowth and cell spreading by a second Nogo domain, termed Amino-Nogo-A, is thought to be mediated by a distinct receptor complex. Here, we define a novel Nogo-A-specific domain in Amino-Nogo that binds to NgR with nanomolar affinity. This second domain of 24 amino acids does not alter cell spreading or axonal outgrowth. Fusion of the two NgR-binding Nogo-A domains creates a ligand with substantially enhanced affinity for NgR and converts a NgR antagonist peptide to an agonist. Thus, NgR activation by Nogo-A involves multiple sites of interaction between Nogo-A and NgR.
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