Current issues in invertebrate phototransduction. Second messengers and ion conductances.
Current issues in invertebrate phototransduction. Second messengers and ion conductances.
复制标题
无脊椎动物光转导的当前问题。
DOI：
10.1007/bf02740615
复制
发表时间：
1997
影响因子：
5.1
通讯作者：
Haab,JE
中科院分区：
文献类型：
--
作者：
O'Day,PM;Bacigalupo,J;Vergara,C;Haab,JE
对无脊椎动物光感受器中的光传导的研究揭示了许多具有基本生物学重要性的生理和生化特征。尽管如此，还没有完整的图片光转导出现。在大多数已知的情况下，无脊椎动物光转导涉及多磷酸肌醇和环GMP（cGMP）细胞内生化信号传导途径，导致质膜离子通道的开放。兴奋是Ca2+依赖性的，调节对光的敏感性的自适应反馈过程也是如此。转导发生在专门的亚细胞区域，丰富的微绒毛和紧密贴壁亚微绒毛膜系统。因此，激发是一个高度局部化的过程。本文主要介绍无脊椎动物光转导中的细胞内生化信号通路和离子通道。对于任何无脊椎动物物种，信号级联与通道激活的耦合尚不清楚。虽然光感受器具有大多数或所有已知无脊椎动物物种共有的特征，但每个物种都表现出独特的特征。比较电生理学，生物化学，形态学和分子生物学的方法来研究这些物种的光转导导致细胞信号的基本见解。评估了当前的几个争议和提出的光转换模型。
Investigation of phototransduction in invertebrate photoreceptors has revealed many physiological and biochemical features of fundamental biological importance. Nonetheless, no complete picture of phototransduction has yet emerged. In most known cases, invertebrate phototransduction involves polyphosphoinositide and cyclic GMP (cGMP) intracellular biochemical signaling pathways leading to opening of plasma membrane ion channels. Excitation is Ca2+-dependent, as are adaptive feedback processes that regulate sensitivity to light. Transduction takes place in specialized subcellular regions, rich in microvilli and closely apposed to submicrovillar membrane systems. Thus, excitation is a highly localized process.This article focuses on the intracellular biochemical signaling pathways and the ion channels involved in invertebrate phototransduction. The coupling of signaling cascades with channel activation is not understood for any invertebrate species. Although photoreceptors have features that are common to most or all known invertebrate species, each species exhibits unique characteristics. Comparative electrophysiological, biochemical, morphological, and molecular biological approaches to studying phototransduction in these species lead to fundamental insights into cellular signaling. Several current controversies and proposed phototransduction models are evaluated.