Polyunsaturated fatty acids activate the Drosophila light-sensitive channels TRP and TRPL
Polyunsaturated fatty acids activate the Drosophila light-sensitive channels TRP and TRPL
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DOI：
10.1038/16703
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发表时间：
1999-01-21
期刊：
影响因子：
64.8
通讯作者：
Hardie, RC
中科院分区：
文献类型：
--
作者：
Chyb, S;Raghu, P;Hardie, RC
无脊椎动物微绒毛光感受器中的光转导被认为是由磷脂酶C（PLC）的活化介导的，但这如何导致光敏通道的门控尚不清楚（1，2）。大多数注意力集中在肌醇-1，4，5-三磷酸，由PLC从磷脂酰肌醇-4，5-二磷酸产生的第二信使;然而，PLC也产生二酰基甘油，几种多不饱和脂肪酸，如花生四烯酸和亚麻酸的潜在前体。在这里，我们表明，这两种脂肪酸可逆地激活天然光敏通道（瞬时受体电位（TRP）和TRP样（TRPL））在果蝇光感受器以及重组TRPL通道表达在果蝇S2细胞。重组通道在全细胞记录和由内而外的斑片中都被迅速激活，亚麻酸的半最大效应物浓度类似于10 μ M。四种不同的脂氧合酶抑制剂，预期可能导致内源性脂肪酸的积累，也激活完整光感受器中的天然TRP和TRPL通道，因为花生四烯酸可能在果蝇中没有发现，我们认为另一种多不饱和脂肪酸，如亚麻酸，可能是果蝇感光细胞兴奋的信使。
Phototransduction in invertebrate microvillar photoreceptors is thought to be mediated by the activation of phospholipase C (PLC), but how this leads to gating of the light-sensitive channels is unknown(1,2). Most attention has focused on inositol-1,4,5-trisphosphate, a second messenger produced by PLC from phosphatidylinositol-4,5-bisphosphate; however, PLC also generates diacylglycerol, a potential precursor for several polyunsaturated fatty acids, such as arachidonic acid and linolenic acid. Here we show that both of these fatty acids reversibly activate native light-sensitive channels (transient receptor potential (TRP) and TRP-like (TRPL)) in Drosophila photoreceptors as well as recombinant TRPL channels expressed in Drosophila S2 cells. Recombinant channels are activated rapidly in both whole-cell recordings and inside-out patches, with a half-maximal effector concentration for linolenic acid of similar to 10 mu M Four different Lipoxygenase inhibitors, which might be expected to lead to build-up of endogenous fatty[GRAPHICS]acids, also activate native TRP and TRPL channels in intact photoreceptors, As arachidonic acid may not be found in Drosophila, we suggest that another polyunsaturated fatty acid, such as linolenic acid, may be a messenger of excitation in Drosophila photoreceptors.