Cryo-EM Reveals How Neuropeptide Y Binds Its Two Main Receptors Differently | Research

The takeaway

High-resolution cryo-EM structures of NPY bound to both Y1 and Y2 receptors revealed a shared binding mode plus a selectivity sub-pocket that has undergone evolutionary adaptation across species.

3 cryo-EM structures
Solved for NPY bound to Y1R and Y2R, revealing the structural basis of receptor selectivity

What the researchers found

Three cryo-EM structures of Gi2-coupled Y1R and Y2R with NPY revealed a conserved peptide-binding mode and an additional sub-pocket conferring ligand selectivity, with evidence of evolutionary adaptation in this selectivity region.

Why it matters

Understanding exactly how NPY binds its different receptor subtypes is crucial for designing drugs that target one receptor without affecting others. This could lead to more precise treatments for conditions like obesity, anxiety, cardiovascular disease, and cancer.

The numbers in context

NPY is a 36-amino-acid peptide. [Pro34]-NPY and [Leu31, Pro34]-NPY mainly act on Y1R; other analogs show Y2R selectivity.

How the study worked

Cryo-electron microscopy (cryo-EM) structural determination of three receptor-peptide complexes: Y1R-NPY, Y1R-[Leu31,Pro34]-NPY, and Y2R-NPY, all coupled to Gi2. Combined with cell-based functional assays and evolutionary analysis.

Who was studied

Structural biology analysis of NPY receptor interactions

What this study cannot tell us

Structures represent receptor complexes stabilized for cryo-EM, which may not capture all conformational states occurring in living cells. The evolutionary analysis of the sub-pocket needs functional validation across species. Clinical drug design based on these structures has not yet been attempted.

How to read the evidence

Preliminary evidence from structural biology. High-quality structural data but functional implications need further validation in physiological settings.

When this study was published

Published in 2024. Represents state-of-the-art cryo-EM structural analysis of peptide-receptor interactions.

The bigger picture

The NPY receptor family is a major drug target, but developing selective drugs has been challenging without knowing the precise structural basis of selectivity. These structures provide a roadmap for rational drug design, potentially enabling highly selective therapeutics that avoid the side effects of activating the wrong receptor subtype.

Questions still open

Can the identified selectivity sub-pocket be exploited to design small-molecule drugs that mimic NPY's receptor-specific effects?
How does the sub-pocket's evolutionary adaptation correlate with functional differences in NPY signaling across species?
What structural changes occur in Y4R and Y5R that determine their distinct selectivity profiles?

Common questions

Why is it important to know how NPY binds to different receptors?

NPY's different receptors control different body functions — Y1R affects blood pressure and anxiety, Y2R regulates neurotransmitter release and blood vessel growth. Knowing the precise binding differences enables designing drugs that target one function without side effects from activating the wrong receptor.

What is cryo-EM and why is it used here?

Cryo-electron microscopy freezes proteins in their natural state and uses electron beams to create detailed 3D images at near-atomic resolution. It's ideal for studying large protein complexes like receptors bound to peptides, which are difficult to crystallize for traditional X-ray methods.

Read the original research

Structural basis of neuropeptide Y signaling through Y1 and Y2 receptors.

MedComm, 5(7), e565

View on PubMed ↗Publisher’s paper ↗

Citation

Shen, Siyuan; Deng, Yue; Shen, Chenglong; Chen, Haidi; Cheng, Lin; Wu, Chao; Zhao, Chang; Yang, Zhiqian; Hou, Hanlin; Wang, Kexin; Shao, Zhenhua; Deng, Cheng; Ye, Feng; Yan, Wei. (2024). Structural basis of neuropeptide Y signaling through Y1 and Y2 receptors.. MedComm, 5(7), e565. https://doi.org/10.1002/mco2.565