Receptor-specific recognition of NPY peptides revealed by structures of NPY receptors

Abstract

In response to three highly conserved neuropeptides, neuropeptide Y (NPY), peptide YY, and pancreatic polypeptide (PP), four G protein–coupled receptors mediate multiple essential physiological processes, such as food intake, vasoconstriction, sedation, and memory retention. Here, we report the structures of the human Y 1 , Y 2 , and Y 4 receptors in complex with NPY or PP, and the G i1 protein. These structures reveal distinct binding poses of the peptide upon coupling to different receptors, reflecting the importance of the conformational plasticity of the peptide in recognizing the NPY receptors. The N terminus of the peptide forms extensive interactions with the Y 1 receptor, but not with the Y 2 and Y 4 receptors. Supported by mutagenesis and functional studies, subtype-specific interactions between the receptors and peptides were further observed. These findings provide insight into key factors that govern NPY signal recognition and transduction, and would enable development of selective drugs.

The Chemerin Receptor CMKLR1 Requires Full‐Length Chemerin for High Affinity in Contrast to GPR1 as Demonstrated by a New Nanoluciferase‐Based Binding Assay

“…In addition, the graph displays a biphasic shape at the CMKLR1 receptor, which points to the characterization of a low and a high affinity state of the C9. Similar biphasic binding curves are described for different GPCRs in binding assay such as Y 1 or Y 2 receptor [28f] . The shape of the curve indicates that the ligand first binds in a loose complex and second in a tightly bound state after conformational changes of the binding partner [30] .…”

“…The shape of the curve indicates that the ligand first binds in a loose complex and second in a tightly bound state after conformational changes of the binding partner [30] . It can be speculated that the G protein might allosterically stabilize the high affinity state of GPCRs [28f] . This suggests that the binding mechanism at the CMKLR1 is more complex, compared to the GPR1.…”

Insertion of Nanoluc into the Extracellular Loops as a Complementary Method To Establish BRET-Based Binding Assays for GPCRs

“…The used fluorescent ligand also plays a substantial role. For example, a BRET-based binding assay with an N-terminally Nluc-tagged Y 1 R has recently been described in combination with a TAMRA-labeled pNPY as the fluorescent ligand, even though this approach did not work robustly with our labeled ligand UR-CM138 ( 1 ). Moreover, BRET binding assays have been described for receptors with substantially larger N-terminal domains than the receptors tested in this study, especially for receptors of the class F. , Therefore, the combination of fluorescent ligand and receptor seems to be the main determinant whether the N-terminal fusion of Nluc results in a functioning binding assay.…”

Dynamic in situ confinement triggers ligand-free neuropeptide receptor signaling

“…Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors (GPCR) are key cell surface proteins that regulate a plethora of cellular responses to external stimuli (Hilger et al ., 2018; Venkatakrishnan et al ., 2013; Wootten et al ., 2018). The Y 2 receptor (Y 2 R) is one of the four human neuropeptide Y (NPY) receptor subtypes, which belong to the rhodopsin-like (class A) GPCR superfamily (Parker & Balasubramaniam, 2008; Tang et al ., 2022). Y 2 R is linked to many important physiological processes, such as fear extinction (Méndez-Couz et al ., 2021), regulation of food intake (Huang et al ., 2014), and obesity (Lafferty et al ., 2021).…”