摘要
The sense of taste plays a critical role in the life and nutritional status of organisms. During the last decade, several molecules involved in taste detection and transduction have been identified, providing a better understanding of the molecular physiology of taste receptor cells. However, a comprehensive catalogue of the taste receptor cell machinery is still unavailable. The Margolskee group has recently identified Trpm5 , using differential screening of cDNAs from individual taste receptor cells. Trpm5 is a novel candidate taste transduction element belonging to the mammalian family of transient receptor potential channels. Trpm5 is expressed in a tissue-restricted manner, with high levels in gustatory tissue. In taste cells, Trpm5 is co-expressed with taste-signaling molecules such as α-gustducin, Gγ13 , phospholipase C β2 and inositol 1,4,5-trisphosphate receptor type III. Biophysical studies of Trpm5 heterologously expressed in Xenopus oocytes and mammalian CHO-K1 cells indicate that it functions as a store-operated channel that mediates capacitative calcium entry. Additionally, it was shown that the bitter-responsive enteroendocrine cell line STC-1 expresses multiple transient receptor potential channels and that capacitative calcium entry is necessary for its chemosensory function. The role of Trpm5 and other transient receptor potential channels in capacitative calcium entry in taste receptor cells in response to bitter and/or sweet compounds is discussed.
摘要译文
味觉起着生物体的寿命和营养状况的关键作用。在过去十年中，涉及味觉检测和转导几个分子已被鉴定，提供了一个更好的理解味觉受体细胞的分子生理学。然而，味觉受体细胞机制的综合目录仍无法使用。该Margolskee小组最近发现TRPM5，利用个人味觉受体细胞cDNA的差异筛选。TRPM5是属于瞬时受体电位通道哺乳动物家族一个新的候选味觉转导元件。TRPM5表达于组织限制性方式，与高水平的味觉组织。在味觉细胞，TRPM5共表达与味觉信号传导分子如α-味转导素，Gγ13，磷脂酶Cβ2，肌醇1,4,5-三磷酸肌醇受体III型。TRPM5异源表达在爪蟾卵母细胞和哺乳动物CHO-K1细胞的生物物理研究表明，它起到介导电容钙进入一个库操纵通道。此外，结果表明，味苦响应肠内分泌细胞系的STC-1表达的多个瞬时受体电位通道，并且电容钙进入是必要的其化学感受功能。TRPM5并且在味觉受体细胞库容性钙进入其他瞬时受体电位通道响应于苦味和/或甜化合物的作用进行了讨论。
Perez, Cristian A. Trpm5 is a novel transient receptor potential channel expressed in taste receptor cells[D]. US: Mount Sinai School of Medicine of New York University, 2003