Ishimoto H, Tanimura T
Department of Biology, Graduate School of Sciences, Kyushu University, 810-8560, Fukuoka, Japan.
Cell Mol Life Sci. 2004 Jan;61(1):10-8. doi: 10.1007/s00018-003-3182-9.
The recent identification of candidate receptor genes for sweet, umami and bitter taste in mammals has opened a door to elucidate the molecular and neuronal mechanisms of taste. Drosophila provides a suitable system to study the molecular, physiological and behavioral aspects of taste, as sophisticated molecular genetic techniques can be applied. A gene family for putative gustatory receptors has been found in the Drosophila genome. We discuss here current knowledge of the gustatory physiology of Drosophila. Taste cells in insects are primary sensory neurons whereupon each receptor neuron responds to either sugar, salt or water. We found that particular tarsal gustatory sensilla respond to bitter compounds. Electrophysiological studies indicate that gustatory sensilla on the labellum and tarsi are heterogeneous in terms of their taste sensitivity. Determination of the molecular bases for this heterogeneity could lead to an understanding of how the sensory information is processed in the brain and how this in turn is linked to behavior.
最近在哺乳动物中鉴定出甜味、鲜味和苦味的候选受体基因，为阐明味觉的分子和神经机制打开了一扇门。果蝇提供了一个合适的系统来研究味觉的分子、生理和行为方面，因为可以应用复杂的分子遗传学技术。在果蝇基因组中发现了一个假定的味觉受体基因家族。我们在此讨论果蝇味觉生理学的当前知识。昆虫中的味觉细胞是初级感觉神经元，每个受体神经元对糖、盐或水作出反应。我们发现特定的跗节味觉感受器对苦味化合物有反应。电生理研究表明，唇和跗节上的味觉感受器在味觉敏感性方面是异质的。确定这种异质性的分子基础可能有助于理解感觉信息在大脑中是如何处理的，以及这反过来又是如何与行为联系起来的。
