TAS1R3
Description
The TAS1R3 (taste 1 receptor member 3) is a protein-coding gene located on chromosome 1.
This protein is encoded by the TAS1R3 gene and is the human homolog of the mouse Sac taste receptor. It is a major factor in determining how sensitive mice are to sugars like sucrose and saccharin. The protein is a G protein-coupled receptor with seven transmembrane domains and works as part of two different receptors: one for amino acids (TAS1R1+3) and one for sweet tastes (TAS1R2+3). It can form a dimer with either TAS1R1 or TAS1R2. Interestingly, it can also form a homodimer and this is thought to be why sugar substitutes don't taste exactly like natural sugars. The TAS1R1+3 receptor responds to glutamate (in MSG) and taste enhancers like IMP and GMP. These enhancers don't activate the receptor alone, but they boost the response to L-amino acids. The TAS1R2+3 receptor is activated by natural sugars like sucrose and fructose, as well as artificial sweeteners like saccharin and acesulfame potassium.
TAS1R3 is also known as T1R3.