Shah Alok S, Ben-Shahar Yehuda, Moninger Thomas O, Kline Joel N, Welsh Michael J
Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA.
Science. 2009 Aug 28;325(5944):1131-4. doi: 10.1126/science.1173869. Epub 2009 Jul 23.
Cilia are microscopic projections that extend from eukaryotic cells. There are two general types of cilia; primary cilia serve as sensory organelles, whereas motile cilia exert mechanical force. The motile cilia emerging from human airway epithelial cells propel harmful inhaled material out of the lung. We found that these cells express sensory bitter taste receptors, which localized on motile cilia. Bitter compounds increased the intracellular calcium ion concentration and stimulated ciliary beat frequency. Thus, airway epithelia contain a cell-autonomous system in which motile cilia both sense noxious substances entering airways and initiate a defensive mechanical mechanism to eliminate the offending compound. Hence, like primary cilia, classical motile cilia also contain sensors to detect the external environment.
纤毛是从真核细胞伸出的微小突起。纤毛主要有两种类型；初级纤毛作为感觉细胞器，而运动纤毛施加机械力。从人类气道上皮细胞伸出的运动纤毛将吸入的有害物质排出肺部。我们发现这些细胞表达感觉苦味受体，其定位于运动纤毛上。苦味化合物增加细胞内钙离子浓度并刺激纤毛摆动频率。因此，气道上皮含有一个细胞自主系统，其中运动纤毛既能感知进入气道的有害物质，又能启动防御性机械机制以清除有害化合物。因此，与初级纤毛一样，经典的运动纤毛也含有检测外部环境的传感器。
