SPLTRAK Abstract Submission
Exploring Food Texture Sensation in Drosophila 
John Mack, Tingwei Mi, Yali Zhang
Monell Chemical Senses Center, Philadelphia, PA, United States

The physical features of food, such as hardness or viscosity, significantly influence food preference in many organisms ranging from humans to fruit flies. Food mechanosensory neurons located at the taste organ detect the physical properties of food, enabling animals to evaluate food stiffness and viscosity. Our previous work using the fruit fly, Drosophila melanogaster as an animal model, has identified a protein named transmembrane channel-like (TMC), which in mammals is critical for hearing, as a vital mechanotransduction component underlying food texture sensation. To further elucidate the food mechanotransduction pathway, we performed an RNAi-based behavioral screen to search for the channel subunits and signaling components governing food texture sensation. Our genetic analyses show that the fly homolog of the mammalian tetraspan membrane protein of hair cell stereocilia (TMHS), is required for food texture sensation. Loss of tmhs leads to severe defects in the discrimination between soft foods containing 1% agarose and hard foods containing 3% agarose. Moreover, tmhs is expressed at the mechanosensory neurons in the fly tongue. In summary, our results implicate the fly tmhs as an essential gene regulating food texture sensation. In mammals including humans, both TMC and TMHS are required for hearing. Of great interest, our work shows that TMC and TMHS are also responsible for food texture sensation in flies. Therefore, we propose that food texture sensation in the fly and hearing in mammals may use a similar mechanotransduction pathway.