抄録
Bitter taste perception is widely known as a key defence against ingestion of toxic components. Bitter recognition is mediated by a bitter receptor encoded by T2R multigene families. One member of T2Rs is T2R38 that encode receptor for phenylthiocarbamide (PTC). In primates, polymorphism in T2R38 had been identified in human, chimpanzee, and Japanese macaques that lead to different behavioral response of individual. Among primates, leaf-eating monkeys (Subfamily Colobines) are unique because their diet consisted mostly of leaves that perceptually tasted bitter to human. Preliminary behavioral experiments of PTC-tasting on leaf-eating monkeys kept in Ragunan Zoo indicated that nine individuals of genus Trachypithecus, Presbytis and Nasalis were all non-tasters. This study aimed to investigate the genetic of that behavioral by sequencing those gene and to assay the sensitivities of T2R38s of leaf-eating monkeys using cell expression system. The sequences of T2R38 gene from leaf-eating monkey indicated that all gene should encode functional protein to taste PTC, in comparison with human taster. Thus, genetic result is in contrary with non-taster result. Then, we expressed those gene in cell expression system and found that some of T2R38s of Colobines showed either low response or no responce against PTC. The result is in match with the behavioral experiment.
