Taste receptor type 2 family (TAS2R) (TAS2R)

The Taste receptor type 2 family (TAS2R) consists of approximately 25 to 30 G protein-coupled receptors (GPCRs) that are primarily known for mediating bitter taste perception in humans [UniProt: Family: Taste receptor type 2 family]. While initially identified in the oral cavity, these receptors are widely expressed in extra-oral tissues, including the respiratory tract, gastrointestinal system, and immune cells [PubMed: 26851177]. In the lungs, TAS2R activation on airway smooth muscle cells triggers a signaling pathway that leads to potent bronchodilation, offering a novel mechanism for treating asthma and chronic obstructive pulmonary disease (COPD) [PubMed: 20972434]. In the gut, TAS2Rs regulate the secretion of satiety hormones like glucagon-like peptide-1 (GLP-1), suggesting a role in metabolic regulation and the treatment of obesity or type 2 diabetes [PubMed: 21430232]. Additionally, TAS2Rs in the nasal epithelium contribute to innate immunity by stimulating nitric oxide production and increasing ciliary beat frequency to clear pathogens [PubMed: 22976231]. Pharmacological targeting of TAS2Rs involves various bitter-tasting compounds, including quinine and chloroquine, as well as synthetic agonists currently under investigation for respiratory and metabolic indications [PubMed: 21106692]. Genetic variations within the TAS2R family, particularly in TAS2R38, are known to influence individual differences in taste perception and have been linked to susceptibility to certain infections and metabolic conditions [PubMed: 12595691].

Other names

T2R familyBitter taste receptor familyTRB familyTaste receptor type 2

Agonism of TAS2R receptors leads to G protein-mediated signaling (typically via G-alpha-gustducin or G-beta-gamma subunits), resulting in phospholipase C activation, intracellular calcium release, and downstream effects such as smooth muscle relaxation in the airways or hormone secretion in the gut [PubMed: 20972434, PubMed: 21430232].