5月5日,，《神經(jīng)科學(xué)雜志》（The Journal of Neuroscience）發(fā)表了中國科學(xué)院上海生命科學(xué)研究院神經(jīng)科學(xué)研究所神經(jīng)環(huán)路與動物行為研究組最新研究成果,。該項工作由博士研究生陳子敬及工作人員王清秀在王佐仁研究員的指導(dǎo)下共同完成,。
在果蠅中,，水可以作為一種獨特的味覺感受,。水通過降低滲透壓的機(jī)制來激活味覺剛毛（taste sensilla）中特定的味覺神經(jīng)元,。但是,，關(guān)于什么分子可作為滲透壓感受器來參與果蠅的味覺水感受,，尚不清楚,。通過藥理學(xué)實驗，陳子敬等發(fā)現(xiàn)上皮鈉通道的阻斷劑amiloride及其類似物能夠特異地拮抗味覺神經(jīng)元（gustatory receptor neurons）對水刺激的電生理反應(yīng),，并抑制果蠅對水的味覺行為,。敲除果蠅上皮鈉通道家族其中一個成員ppk28基因，可以使得味覺神經(jīng)元對水的電生理反應(yīng)幾乎完全消失,，并降低果蠅對水的味覺行為反應(yīng),。將PPK28通道異位表達(dá)在中間型味覺剛毛（intermediate-type taste sensilla）的苦味細(xì)胞中，可以使中間型味覺剛毛獲得應(yīng)答水刺激的能力,。這些研究結(jié)果提示PPK28通道作為滲透壓感受器,，參與果蠅的味覺水感受。
PPK28介導(dǎo)果蠅味覺水感受（圖片來源：ＳＩＢＳ）
該工作得到了中國科學(xué)院,、科技部與國家自然科學(xué)基金等項目的資助,。（生物谷Bioon.com）
生物谷推薦原文出處：
The Journal of Neuroscience doi:10.1523/JNEUROSCI.0627-10.2010
The Amiloride-Sensitive Epithelial Na+ Channel PPK28 Is Essential for Drosophila Gustatory Water Reception
Zijing Chen,1,2 Qingxiu Wang,1 and Zuoren Wang1
1 Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences and
2 Graduate School, Chinese Academy of Sciences, Shanghai 200031, China
Water sensation is a specific taste modality in the fruit fly. Water-induced hypoosmolarity activates specific gustatory receptor neurons; however, the molecular identity of the putative osmolarity sensor in these neurons remains unknown. We found that amiloride and its analogs specifically antagonized the response of water gustatory receptor neurons and the behavior of flies toward water stimulation. Deletion of the gene that encodes the amiloride-sensitive PPK28 channel, a DEG/eNaC (degenerin/epithelial sodium channel) family member, abolished the water-induced activity of water gustatory receptor neurons and greatly diminished the behavioral response of flies to water. Ectopic expression of the PPK28 channel in the bitter cells within the intermediate-type sensilla renders these sensilla responsive to water stimuli. Thus, the amiloride-sensitive PPK28 channel may serve as the osmolarity sensor for gustatory water reception in the fruit fly.
