Bertrand D, Ballivet M, Gomez M, Bertrand S, Phannavong B, Gundelfinger E D
Department of Physiology, CMU, Geneva, Switzerland.
Eur J Neurosci. 1994 May 1;6(5):869-75. doi: 10.1111/j.1460-9568.1994.tb00997.x.
Three cDNAs (ALS, D alpha 2 and ARD) isolated from the nervous system of Drosophila and encoding putative nicotinic acetylcholine receptor subunits were expressed in Xenopus oocytes in order to study their functional properties. Functional receptors could not be reconstituted from any of these subunits taken singly or in twos and threes. In contrast, large evoked currents (in the microA range) were consistently observed upon agonist application on oocytes co-injected with ALS or D alpha 2 in combination with the chick beta 2 structural subunit. The ALS/beta 2 and D alpha 2/beta 2 receptors are highly sensitive to acetylcholine and nicotine, and their physiological properties resemble those of native or reconstituted receptors from vertebrates. Although the physiological properties of ALS/beta 2 and D alpha 2/beta 2 receptors are quite similar, clear differences appear in their pharmacological profiles. The ALS/beta 2 receptor is highly sensitive to alpha-bungarotoxin while the D alpha 2/beta 2 receptor is totally insensitive to this agent. These results demonstrate that the Drosophila ALS and D alpha 2 cDNAs encode neuronal nicotinic subunits responding to physiological concentrations of the agonists acetylcholine and nicotine.
从果蝇神经系统中分离出的三个cDNA（ALS、Dα2和ARD），编码假定的烟碱型乙酰胆碱受体亚基，为研究其功能特性，将它们在非洲爪蟾卵母细胞中进行表达。单独或两两、三个组合的这些亚基均无法重构出功能性受体。相反，在与鸡β2结构亚基共同注射的卵母细胞上施加激动剂时，始终能观察到较大的诱发电流（在微安范围内）。ALS/β2和Dα2/β2受体对乙酰胆碱和尼古丁高度敏感，其生理特性类似于脊椎动物的天然或重构受体。尽管ALS/β2和Dα2/β2受体的生理特性非常相似，但它们的药理学特征存在明显差异。ALS/β2受体对α-银环蛇毒素高度敏感，而Dα2/β2受体对该试剂完全不敏感。这些结果表明，果蝇的ALS和Dα2 cDNA编码对激动剂乙酰胆碱和尼古丁的生理浓度有反应的神经元烟碱型亚基。
