Photoreceptor responses of fruitflies with normal and reduced arrestin content studied by simultaneous measurements of visual pigment fluorescence and ERG.
Photoreceptor responses of fruitflies with normal and reduced arrestin content studied by simultaneous measurements of visual pigment fluorescence and ERG.
复制标题
通过同时测量视觉色素荧光和ERG研究的水果粉感受器的感受器反应。
DOI：
10.1007/s00359-009-0489-5
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发表时间：
2010-01
影响因子：
2.1
通讯作者：
Stavenga, Doekele G.
中科院分区：
文献类型：
--
作者：
Belusic, Gregor;Pirih, Primoz;Stavenga, Doekele G.
在一定的刺激波长和强度下，我们同时测定了白眼果蝇、野生型果蝇和arrestin2半胚突变体（w−;arr2 3）的视网膜电图（ERG）和后视紫红质含量。光感受器反应振幅和终止（完全复极化和延长去极化后电位之间的过渡，PDA）与视色素转换和抑制素浓度有关。这些数据是在视紫红质-抑制素循环的动力学模型中实现的，使我们能够估计活性后视紫红质浓度作为有效光强和抑制素浓度的函数。突变体中抑制素的减少适度地增加了光敏感性，降低了光感受器的动态范围。与野生型相比，突变体从完全复极化到PDA的转变发生在较低的后视紫红质分数上，并且更加突然。我们建立了一个稳态随机模型来解释PDA对有效光强和抑制蛋白含量的依赖，并帮助从灵敏度和PDA数据推断出抑制蛋白与视紫红质之比。讨论了用不同的实验方法从ERG和PDA中估计阻搏素含量的可行性。
We have simultaneously measured the electroretinogram (ERG) and the metarhodopsin content via fluorescence in white-eyed, wild-type Drosophila and the arrestin2 hypomorphic mutant (w −;arr2 3) at a range of stimulus wavelengths and intensities. Photoreceptor response amplitude and termination (transition between full repolarization and prolonged depolarizing afterpotential, PDA) were related to visual pigment conversions and arrestin concentration. The data were implemented in a kinetic model of the rhodopsin–arrestin cycle, allowing us to estimate the active metarhodopsin concentration as a function of effective light intensity and arrestin concentration. Arrestin reduction in the mutant modestly increased the light sensitivity and decreased the photoreceptor dynamic range. Compared to the wild type, in the mutant the transition between full repolarization and PDA occurred at a lower metarhodopsin fraction and was more abrupt. We developed a steady-state stochastic model to interpret the dependence of the PDA on effective light intensity and arrestin content and to help deduce the arrestin to rhodopsin ratio from the sensitivity and PDA data. The feasibility of different experimental methods for the estimation of arrestin content from ERG and PDA is discussed.
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DOI：
10.1085/jgp.77.2.155
发表时间：
1981-02
期刊：
The Journal of general physiology
影响因子：
--
作者：
Lo MV;Pak WL
通讯作者：
Pak WL
DOI：
10.1007/bf00709805
发表时间：
1975-01-01
期刊：
JOURNAL OF COMPARATIVE PHYSIOLOGY
影响因子：
--
作者：
MINKE, B;WU, CF;PAK, WL
通讯作者：
PAK, WL
影响因子：
3.8
作者：
HOCHSTRATE, P;HAMDORF, K
通讯作者：
HAMDORF, K
影响因子：
2.9
作者：
Kim, JE;Tauber, MJ;Mathies, RA
通讯作者：
Mathies, RA
影响因子：
3.8
作者：
Juusola, M;Hardie, RC
通讯作者：
Hardie, RC