Raghu Padinjat, Yadav Shweta, Mallampati Naresh Babu Naidu
National Centre for Biological Sciences, TIFR, GKVK Campus, Bellary Road, Banglore 560065, India.
Biochim Biophys Acta. 2012 Aug;1821(8):1154-65. doi: 10.1016/j.bbalip.2012.03.008. Epub 2012 Mar 29.
Drosophila photoreceptors are sensory neurons whose primary function is the transduction of photons into an electrical signal for forward transmission to the brain. Photoreceptors are polarized cells whose apical domain is organized into finger like projections of plasma membrane, microvilli that contain the molecular machinery required for sensory transduction. The development of this apical domain requires intense polarized membrane transport during development and it is maintained by post developmental membrane turnover. Sensory transduction in these cells involves a high rate of G-protein coupled phosphatidylinositol 4,5 bisphosphate [PI(4,5)P(2)] hydrolysis ending with the activation of ion channels that are members of the TRP superfamily. Defects in this lipid-signaling cascade often result in retinal degeneration, which is a consequence of the loss of apical membrane homeostasis. In this review we discuss the various membrane transport challenges of photoreceptors and their regulation by ongoing lipid signaling cascades in these cells. This article is part of a Special Issue entitled Lipids and Vesicular Transport.
果蝇光感受器是感觉神经元，其主要功能是将光子转化为电信号，以便向前传递至大脑。光感受器是极化细胞，其顶端区域组织成质膜的指状突起，即微绒毛，其中包含感觉转导所需的分子机制。这个顶端区域的发育在发育过程中需要强烈的极化膜转运，并且通过发育后的膜周转来维持。这些细胞中的感觉转导涉及G蛋白偶联的磷脂酰肌醇4,5-二磷酸[PI(4,5)P(2)]的高速水解，最终激活作为TRP超家族成员的离子通道。这种脂质信号级联反应中的缺陷通常会导致视网膜变性，这是顶端膜稳态丧失的结果。在这篇综述中，我们讨论了光感受器面临的各种膜转运挑战以及这些细胞中持续的脂质信号级联反应对它们的调节。本文是名为“脂质与囊泡运输”的特刊的一部分。
