# Isolation of GPR160 for biochemical analysis of the activation mechanism and development of a high throughput screening assay to identify small molecule inhibitors

> **NIH NIH R01** · SAINT LOUIS UNIVERSITY · 2020 · $151,455

## Abstract

The proposed research supplements the HEAL grant "Discovery and validation of a novel orphan GPCR
as a target for therapeutic intervention in neuropathic pain" (R01NS113257). Neuropathic pain conditions
are exceedingly difficult to treat1-4 and novel non-narcotic analgesics are desperately needed. Our recent work
led to the discovery that activation of the orphan G protein-coupled receptor 160 (oGPCR; GPR160) in the
spinal cord contributes to the development of neuropathic pain states5. Since there are no small molecule
antagonists of GPR160, contribution of GPR160 signaling was unraveled using genetic and
immunopharmacological approaches. Blocking GPR160 blocks and reverses neuropathic pain with no effect in
acute pain settings, suggesting that GPR160 is important in the transition from acute to chronic pain. We also
de-orphanized GPR160 and identified cocaine- and amphetamine-regulated transcript peptide (CARTp) as a
ligand.5 Blocking endogenous CARTp signaling in the spinal cord attenuates neuropathic pain, whereas
intrathecal injection of CARTp evokes painful hypersensitivity in rodents through GPR160-dependent
extracellular signal-regulated kinase (ERK) and cyclic AMP response element-binding pathways (CREB). Our
findings are the first to de-orphanize GPR160, identify it as a determinant of neuropathic pain and potential
therapeutic target with non-opioid based small molecule GPR160 antagonists, and provide insights to its
signaling pathways.5 GPR160 has never been isolated and biochemically characterized and studies to
understand the direct interaction of CARTp with the purified protein have never been done.5 Here, we propose
to isolate and biochemically characterize GPR160, currently identified as one of the Understudied
Druggable Genome targets, and to establish methods for biochemical characterization of GPR160
interaction with CARTp activator. We will miniaturize and optimize biochemical assay and scale up
protein production for future high throughput biochemical screening to identify potent inhibitors of
GPR160 activation. Specifically, we will develop GPR160 expression system(s) and purification protocol(s)
and will characterize/optimize stability and solubility of the receptor for biochemical studies using a nanodisc
approach. We will characterize direct interaction of GPR160 and CARTp using purified proteins and
complementary binding assays such as fluorescence polarization (FP) with fluorescein-labeled (FAM-) CARTp
and surface plasmon resonance (SPR) using unlabeled CARTp. These studies are critical for defining the
molecular mechanism of CARTp/GPR160 interactions and initiating large-scale screens for new inhibitors to
develop novel therapeutics.
 Impact: Discovery and development of small molecule GPR160 antagonists as non-addictive analgesics is
anticipated to have a huge impact on the treatment of chronic pain patients.

## Key facts

- **NIH application ID:** 10176852
- **Project number:** 3R01NS113257-01S1
- **Recipient organization:** SAINT LOUIS UNIVERSITY
- **Principal Investigator:** DANIELA SALVEMINI
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $151,455
- **Award type:** 3
- **Project period:** 2020-09-01 → 2021-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10176852

## Citation

> US National Institutes of Health, RePORTER application 10176852, Isolation of GPR160 for biochemical analysis of the activation mechanism and development of a high throughput screening assay to identify small molecule inhibitors (3R01NS113257-01S1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10176852. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*