As one of the world's leading antibody suppliers, Novus Biologicals has an expansive GPCR (G-protein coupled receptor) antibody catalog. Novus antibodies to the bitter taste receptor (TAS2R) have recently been used in a study on TAS2R bronchodilator activity in human airways.
The G-protein Gustducin plays an important role in the transduction of gustatory (taste) stimuli, especially with respect to bitter stimuli. TAS2R is linked to Gustducin and is thought to play a role in bitter taste detection. Antibody studies suggest it may mediate alpha gustducin expression and PLC-beta-2 activation, and be involved in TRPM5 gating.
TAS2R receptors are thought to be expressed exclusively in gustducin-positive cells on the tongue, and to have evolved as a protective mechanism against plant toxin ingestion. However a new study, conducted by D.A Deshpande, et al, reported TAS2R receptors on the smooth muscle of human airways (ASM). They considered the purpose might similarly be as avoidance receptors, against inhaled toxins which could lead to bronchospasm by smooth muscle contraction.
They noted that bitter tasting TAS2R agonists, including saccharin, chloroquine and denatonium, induced enhanced levels of intracellular calcium (Ca2+) in ASM cells. The receptors involved were the same as those engaged in the contraction response. However, the bitter tasting agonists actually caused relaxation in isolated cells, with airways dilation three times greater than that seen with Beta agonist drugs such as Salbutamol.
It was suggested that TAS2R-induced relaxation occurred as a result of a localised Ca2+ response at the cell membrane. This led to the opening of large-conductance Ca2+ activated potassium channels, leading to hyperpolarization of the smooth muscle membrane. A mouse model of bronchocontraction supported this. It is hoped further TAS2R antibody studies will lead to the development of novel bronchodilator therapies.
Novus Biologicals offers many TAS2R reagents for your research needs including:
