The perception of sweet taste has fascinated philosophers, cooks and scientists for centuries, but the molecular mechanisms involved in taste perception remained elusive. In August 10 Cell, Greg Nelson and colleagues from the University of California at San Diego, La Jolla, US dissect the signal detection of taste and report the characterization of new mammalian sweet receptors present on the cells of the tongue and palate.

Nelson et al. developed transgenic rescue experiments to prove that the Sac locus encodes T1R3, a member of the T1R family of candidate taste receptors. With a heterologous expression system, they demonstrated that T1R2 and T1R3 combine to function as a sweet receptor, recognizing sweet-tasting molecules as diverse as sucrose, saccharin, dulcin, and acesulfame-K (Cell 2001, 106:381-390).

The authors had previously identified the T2Rs receptors involved in bitter taste perception and now show that sweet and bitter receptors are present...