A genetic platform for functionally profiling odorant receptors in olfactory cilia ex vivo

Area of Science:

• Neuroscience
• Molecular Biology
• Sensory Biology

Background:

• The molecular mechanisms of human odor perception are poorly understood due to challenges in studying odorant receptors (ORs) in vitro.
• Previous attempts at OR expression and functional analysis have been limited by inefficient cell surface expression.

Purpose of the Study:

• To develop a sensitive and scalable ex vivo platform for studying human odorant receptors and odor perception.
• To overcome limitations of in vitro OR studies by utilizing olfactory cilia.

Main Methods:

• Isolated olfactory cilia from mice engineered to express human OR1A1 and OR5AN1.
• Utilized an ex vivo plate assay with the isolated cilia to measure odorant responses.
• Developed a pipeline for cilia isolation, storage, and high-throughput screening.

Main Results:

• The developed platform demonstrated 10- to 100-fold increased sensitivity to odorant ligands compared to prior assays.
• A single mouse provided sufficient olfactory cilia for approximately 4000 assay wells.
• Isolated cilia remained viable after frozen storage, enabling preserved sample use.

Conclusions:

• This ex vivo olfactory cilia platform offers a highly sensitive and scalable method for odor screening.
• The platform has significant potential for decoding the complexities of human olfaction.
• The approach facilitates functional profiling of human odorant receptors outside their native cellular environment.