Evaluating cell-surface expression and measuring activation of mammalian odorant receptors in heterologous cells

Area of Science:

• Neuroscience
• Molecular Biology
• Biochemistry

Background:

• Understanding odorant receptor (OR) activation is crucial in olfaction research.
• A significant challenge has been expressing mammalian ORs in heterologous systems for ligand screening.
• Receptor-transporting proteins have enabled effective cell-surface expression of ORs.

Purpose of the Study:

• To establish a robust protocol for heterologous expression of mammalian ORs.
• To facilitate high-throughput deorphanization of ORs by identifying their cognate ligands.
• To detail methods for evaluating cell-surface expression and functional activation of ORs.

Main Methods:

• Utilizing HEK293T cells for transient expression of mammalian ORs.
• Employing immunocytochemistry or flow cytometry to detect cell-surface OR expression.
• Measuring functional receptor activation through odorant stimulation and luciferase assays.

Main Results:

• The protocol enables efficient cell-surface expression of mammalian ORs in HEK293T cells.
• Functional activation of ORs by odorants can be reliably measured.
• The entire process, from cell transfer to detection, can be completed within 3 days.

Conclusions:

• This developed heterologous expression system significantly advances the study of odorant-OR relationships.
• The protocol supports high-throughput deorphanization, accelerating the identification of OR-ligand pairs.
• This method provides a powerful tool for olfactory research and drug discovery.