Olfactory-like receptor cDNAs are present in human lingual cDNA libraries

Area of Science:

• Molecular Biology
• Genetics
• G-protein-coupled Receptors

Background:

• Olfactory receptors (ORs) are G-protein-coupled receptors crucial for detecting odorant signals.
• Previous research identified OR gene expression in fetal human tongue, with reduced expression in adults, hinting at developmental roles.
• The precise function of ORs in non-olfactory tissues, like the tongue, remains largely unexplored.

Purpose of the Study:

• To investigate the expression of olfactory-like genes in adult human tongue epithelial cells.
• To identify specific OR genes present in the adult tongue and compare their expression profiles.
• To provide further insights into the potential functions of ORs in the human tongue.

Main Methods:

• Synthesized and screened a cDNA library from human adult tongue epithelial cells.
• Performed PCR analysis using degenerate primers targeting conserved transmembrane domains of ORs.
• Utilized specific primers to compare the expression profiles of previously identified OR genes.

Main Results:

• Identified and described partial cDNAs of olfactory-like receptors from the adult tongue library.
• Confirmed the expression of four OR genes (HTPCR06, JCG3, JCG5, and JCG6) in adult tongue epithelial cells.
• Discovered the expression of three additional olfactory-like receptor genes (OR7A5/HTPCR2, OR6Q1, and OR7C1/TPCR86) in these cells.

Conclusions:

• Olfactory-like receptors are expressed in the epithelial cells of the adult human tongue.
• The identified ORs may play functional roles in the tongue, potentially beyond chemosensation.
• This study expands the known expression patterns of ORs, highlighting their presence in non-olfactory tissues.