THE TRP GENE IS ESSENTIAL FOR A LIGHT-ACTIVATED CA2+ CHANNEL IN DROSOPHILA PHOTORECEPTORS
THE TRP GENE IS ESSENTIAL FOR A LIGHT-ACTIVATED CA2+ CHANNEL IN DROSOPHILA PHOTORECEPTORS
复制标题
DOI：
10.1016/0896-6273(92)90086-s
复制
发表时间：
1992-04-01
期刊：
影响因子：
16.2
通讯作者：
MINKE, B
中科院分区：
文献类型：
--
作者：
HARDIE, RC;MINKE, B
无脊椎动物的光转导是研究肌醇-脂质信号转导系统的重要模型。在瞬时受体电位（trp）突变体，最深入研究的果蝇转导突变体之一，光反应迅速下降到基线在长时间的强光。使用果蝇光感受器的全细胞记录，我们表明，野生型响应介导的至少两个功能不同的类的光敏感通道和这两个色氨酸突变和Ca 2+通道阻滞剂（La 3+）选择性地取消一类通道具有高Ca 2+渗透性。证据还提出，Ca 2+是必要的激励和Ca 2+耗竭模仿的色氨酸表型。我们的结论是，最近测序的色氨酸蛋白代表一类的肌醇介导的Ca 2+进入所需的光敏通道，并建议这个过程是必要的，在强烈的照明过程中保持激发在飞光感受器。
Invertebrate phototransduction is an important model system for studying the ubiquitous inositol-lipid signaling system. In the transient receptor potential (trp) mutant, one of the most intensively studied transduction mutants of Drosophila, the light response quickly declines to baseline during prolonged intense light. Using whole-cell recordings from Drosophila photoreceptors, we show that the wild-type response is mediated by at least two functionally distinct classes of light-sensitive channels and that both the trp mutation and a Ca2+ channel blocker (La3+) selectively abolish one class of channel with high Ca2+ permeability. Evidence is also presented that Ca2+ is necessary for excitation and that Ca2+ depletion mimics the trp phenotype. We conclude that the recently sequenced trp protein represents a class of light-sensitive channel required for inositide-mediated Ca2+ entry and suggest that this process is necessary for maintained excitation during intense illumination in fly photoreceptors.