# HPLC Purification of TRPM8 and Experimental Confirmation of Its Cholesterol Affinity on Synthetic Lipid Raft-like Models

## TL;DR

Researchers purified the TRPM8 ion channel and found it strongly binds to cholesterol in synthetic membranes, suggesting cholesterol's role in its function.

## Contribution

The study introduces a novel HPLC-based purification method and confirms TRPM8's cholesterol affinity using synthetic lipid raft models.

## Key findings

- TRPM8 was successfully purified using HPLC-SEC and a modified bacterial expression protocol.
- TRPM8 shows strong and selective affinity for cholesterol-containing membranes in FRET-based assays.
- The findings establish a model system for studying membrane-associated proteins like TRPM8.

## Abstract

This study presents the successful expression, purification, and functional characterization of the human TRPM8 ion channel, a key player in temperature sensing and pain modulation. Using a modified bacterial expression protocol and DDM-based solubilization, TRPM8 was purified via HPLC-SEC and analyzed for its membrane-binding properties. FRET-based assays with synthetic lipid rafts revealed a strong and selective affinity of TRPM8 for cholesterol-containing membranes, suggesting cholesterol’s role in modulating TRPM8 localization and activity. These findings provide quantitative in vitro evidence of TRPM8–cholesterol interactions and establish a robust model system for future structural and functional studies of membrane-associated proteins.