Membrane Protein Transport in Photoreceptors

光感受器中的膜蛋白转运

基本信息

批准号：
8756527
负责人：
WOLFGANG BAEHR
金额：
$ 37.25万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-12-01 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8756527
关键词：
Abbreviations Address Adenylate Cyclase Affect Afferent Neurons Affinity Chromatography Alleles Animals Antibodies Binding Binding Proteins Brain Calcium-Binding Proteins Calmodulin Cell Culture Techniques Cell Line Cell Nucleus Cell membrane Cells Cellular biology Choroideremia Cilia Cilium Microtubule Complex Defect Disease Docking Dominant-Negative Mutation Drosophila genus Dysosmia EF Hand Motifs Endoplasmic Reticulum Etiology Exhibits Family Genes Golf Golgi Apparatus Green Algae Guanosine Triphosphate Phosphohydrolases Guanylate Cyclase Human Hydrocephalus In Vitro Integral Membrane Protein Joubert syndrome Knock-out Knockout Mice Life Male Infertility Mammalian Cell Membrane Membrane Protein Traffic Membrane Proteins Membrane Transport Proteins MicroRNAs Microtubule-Organizing Center Microtubules Modeling Mus Opsin Pathway interactions Patients Phenotype Photons Photoreceptors Phototransduction Plants Process Protein Isoforms Proteins Regulation Research Retinal Degeneration Retinal Diseases Retinitis Pigmentosa Rhodopsin Ribosomes Role Site Situs Inversus Spermiogenesis Structure Syndrome Tail Tamoxifen Technology Testing Transducin Trimethoprim-Sulfamethoxazole Vesicle Virus Xenopus analog base ciliopathy cilium biogenesis gene replacement therapy gene therapy human disease immortalized cell kinetosome member mouse model mutant peripherin photoreceptor degeneration polypeptide protein transport public health relevance research study retinal rods small hairpin RNA sperm cell trafficking trans-Golgi Network vector

项目摘要

DESCRIPTION (provided by applicant): Photoreceptor outer segment membranes, the site of initial photon capture initiating phototransduction, undergo renewal with total replacement occurring at ten day intervals throughout life. A challenge to cellular integrity concerns the post biosynthetic delivery of replacement proteins from the inner, to the outer, segment over the lifetime of the photoreceptor. Complex trafficking pathways require multiple components, such as acyl-binding proteins, Rab GTPases and centrins. This application will identify: i) key Rab GTPases involved in vesicular transport of membrane protein, and ii) centrins participating in ciliary transport. Aim 1 will focus on Rab GTPases in photoreceptor vesicular transport. Rab (Ras analog in brain) proteins are members of the Ras supergene family involved mainly in membrane protein trafficking. More than 70 distinct Rab polypeptides have been identified. Aim 1a focuses on Rab8 and Rab11 isoforms which are known to be important for photoreceptor trafficking in Xenopus and Drosophila models. Surprisingly, a mouse Rab8a/Rab11a double knockout does not produce a defective trafficking phenotype. Therefore, we will focus on closely-related isoforms to identify key Rab proteins responsible for membrane protein organization and rhodopsin trafficking. Aim 1b investigates Rab28, shown recently associated with recessive human cone/rod dystrophy. Aim 2 will examine the function of centrosomal proteins, called "centrins," which are 20kD EF- hand calcium binding proteins (four EF-hand motifs) of the calmodulin superfamily. Centrins were first described in unicellular green algae where they are associated with the flagellar basal apparatus. Photoreceptor centrins (isoforms 1-4) are located in the ciliary lumen and basal body where they associate with transducin via its T¿?-subunits. One hypothesis is that centrins may be involved in regulation of transducin translocation from the outer, to the inner, segment or vice-versa. As preliminary results, we found that centrin1 is required for the nucleus-basal body connection during mouse spermiogenesis, and centrin2 regulates trafficking of ACIII and channel subunits in olfactory sensory neurons. This aim seeks to identify the roles of photoreceptor centrin3 and centrin4 which associate strongly with the basal body and/or connecting cilium axoneme. We expect to generate mouse models of syndromic disease with retina degeneration, e.g., Joubert or Senior-Loken syndromes.

描述（由应用程序提供）：光感受器外部段膜，初始光子捕获的部位引发的光转移，经历了续订，总替换在整个生命中以十天的间隔发生。蜂窝完整性的挑战涉及该职位在光感受器的寿命中，替代蛋白从内部到外部的生物合成递送。复杂的运输途径需要多个组件，例如酰基结合蛋白，RAB GTPases和Centrins。该应用将确定：i）参与膜蛋白囊泡转运的关键RAB GTPase，以及II）参与睫状转运的中心素。 AIM 1将重点放在光感受器囊泡转运中的RAB GTPase上。 RAB（大脑中的RAS类似物）蛋白是主要参与膜蛋白运输的RAS超基因家族的成员。已经确定了70多种不同的RAB多肽。 AIM 1A的重点是Rab8和Rab11同工型，这些同工型对于在Xenopus和果蝇模型中的光感受器运输很重要。令人惊讶的是，小鼠RAB8A/RAB11A双重敲除不会产生有缺陷的运输表型。因此，我们将重点放在与密切相关的同工型上，以识别负责膜蛋白质组织和视紫红质运输的关键RAB蛋白。 AIM 1B研究了最近与隐性人锥/杆营养不良有关的RAB28。 AIM 2将检查中心蛋白的功能，称为“中心素”，该蛋白是钙调蛋白超家族的20kD EF手钙结合蛋白（四个EF手基序）。首先在单细胞绿藻类中描述了中心素，它们与鞭毛基型相关。光感受器中心素（同工型1-4）位于睫状管道和基本体中，它们通过其T€？subunits与转霉素相关。一种假设是，中心素可能参与了从外部，到内部，段或反之亦然的跨核素易位的调节。作为初步结果，我们发现小鼠精子发生过程中的核基体连接需要Centrin1，并且Centrin2调节嗅觉感觉神经元中ACIII和通道亚基的运输。该目标旨在确定光感受器Centrin3和Centrin4与基本体和/或连接纤毛轴突的作用。我们希望通过视网膜变性产生综合症的小鼠模型，例如Joubert或高级综合症。