Endothelin-converting enzyme 2 regulates κ opioid receptor trafficking and function.

Area of Science:

• Neuroscience
• Biochemistry
• Pharmacology

Background:

• Endothelin-converting enzyme 2 (ECE2) processes neuropeptides and influences μ and δ opioid receptor recycling.
• The role of ECE2 in κ opioid receptor (KOR) regulation remains less understood.

Purpose of the Study:

• To investigate the interaction between ECE2 and KOR.
• To examine how ECE2 substrates modulate KOR internalization and recycling.
• To assess the impact of ECE2 inhibition on KOR function.

Main Methods:

• Proximity-based ligation assay to detect KOR-ECE2 interaction.
• Treatment with ECE2 substrate and non-substrate peptides.
• Analysis of receptor internalization and recycling kinetics.
• Pharmacological inhibition of ECE2 in recombinant and endogenous systems.

Main Results:

• KOR and ECE2 directly interact and cointernalize upon peptide treatment.
• Peptide-induced internalization and recycling of ECE2 mirrors that of KOR.
• ECE2 inhibition attenuates KOR recycling and signaling mediated by ECE2 substrates.
• Differential ECE2 expression observed across brain regions.

Conclusions:

• ECE2 plays a critical role in modulating KOR function, particularly with ECE2 substrate peptides.
• ECE2 activity is essential for agonist-mediated KOR recycling and signaling.
• ECE2 inhibitors represent a potential therapeutic strategy for KOR-related dysfunctions.