Single cell transcriptome analysis of mouse carotid body glomus cells

Area of Science:

• Physiology
• Molecular Biology
• Genomics

Background:

• The carotid body (CB) is crucial for arterial chemoreception, sensing oxygen levels.
• Glomus cells within the CB initiate the hypoxic ventilatory response.
• Limited understanding of CB glomus cell molecular mechanisms and signaling pathways exists.

Purpose of the Study:

• To establish the first transcriptome profile of carotid body (CB) glomus cells.
• To identify novel genes and signaling pathways involved in CB chemosensory function.
• To utilize single-cell RNA sequencing (scRNA-Seq) for precise glomus cell gene identification.

Main Methods:

• Single-cell RNA sequencing (scRNA-Seq) of isolated CB glomus cells.
• Next-generation sequencing of single glomus cell-derived cDNAs.
• Heterologous cell-based screening and functional assays.
• In situ hybridization and immunohistochemistry for validation.

Main Results:

• scRNA-Seq identified highly expressed and novel genes in CB glomus cells.
• Key findings include G protein-coupled receptors, ion channels, and mitochondrial components.
• Olfactory receptor 78 (Olfr78) identified as the most abundant G protein-coupled receptor, activated by acetate.
• Atypical mitochondrial electron transport chain subunits (Ndufa4l2, Cox4i2) were specifically expressed.

Conclusions:

• The study provides the first comprehensive transcriptome of CB glomus cells.
• Identified genes offer insights into oxygen sensing and chemosensory mechanisms.
• Olfr78 and mitochondrial subunits are highlighted for their potential roles in CB function.