The Role of TULP1 in Photoreceptor Cells

TULP1是我们发现的导致常染色体隐性遗传性视网膜色素变性的基因 退化导致全球近100万人失明。已知的RP的遗传病因约有50% 然而，导致这种疾病的生化途径要少得多。整体而言 本研究的目的是探讨TULP1在视网膜中的生理功能，以及 明确与TULP1突变相关的导致光感受器退化的病理机制。 Tulp家族由四种功能未知的蛋白质组成，其中两种与光感受器有关 退化。 这个应用程序的两个特定目标旨在测试TULP1是一个 光感受器中参与蛋白质定向移位的分子机制的组成部分 细胞。第一个特定的目的是确定TULP1在光感受器运输途径中的作用。这将是 通过使用免疫细胞化学来确定细胞内的外段蛋白是否 运输蛋白和突触蛋白在tulpt-/-retinas中被错误定位。免疫电子显微镜将 以确定错误运输的蛋白质是否是细胞外的货物 郁金香--视网膜内的小泡。第二个具体目标是确定TULP1/Dynamin-1的功能 在感光细胞中发现的相互作用。这将通过确定以下功能域来实现 TULP1和Dynamin-1之间的相互作用以及确定导致RP的TULP1突变是否改变 这两种蛋白质之间的结合。还建议进行实验，以产生和表型缺乏的小鼠 利用Cre-loxP突变的光感受器细胞中的Dynamin-1。运输路径将在#年进行评估 这些小鼠如目标1所述。 由于对Tulp蛋白知之甚少，因此发现关于Tulp蛋白功能的信息 应该提供有关光感受器退化途径的知识。有可能是 这项工作可以为未来旨在评估治疗方式的研究奠定基础 延缓、阻止或逆转视网膜变性的进程。

TULP1 is a gene we identified to cause autosomal recessive retinitis pigmentosa, a hereditary retinal degeneration blinding nearly 1 million people worldwide. The genetic etiology of RP is known for about 50% of cases; however, the biochemical pathways involved in causing the disease much less. The overall objectives of the proposed studies are to explore the physiologic function of TULP1 in the retina and to define the pathologic mechanism leading to photoreceptor degeneration associated with TULP1 mutations. The TULP family consists of four proteins of unknown function, two of which are linked to photoreceptor degeneration. The two specific aims of this application are designed to test the central hypothesis that TULP1 is a component of the molecular machinery involved in the directional translocation of proteins in photoreceptor cells. The first specific aim is to determine the role of TULP1 in photoreceptor transport pathways. This will be accomplished by using immunocytochemistry to determine whether outer segment proteins, intracellular transport proteins and synaptic proteins are mistargeted in tulpt-/- retinas. Immunoelectron microscopy will be performed to determine if the proteins that are incorrectly transported are cargo on the extracellular vesicles in tulpl-/- retinas. The second specific aim is to determine the function of the TULP1/Dynamin-1 interaction identified in photoreceptor cells. This will be done by identifying the functional domains that interact between TULP1 and Dynamin-1 and determining whether TULP1 mutations that cause RP alter the binding between the two proteins. Experiments are also proposed to generate and phenotype mice lacking Dynamin-1 in photoreceptor cells using Cre-loxP mutagenesis. Transport pathways will be evaluated in these mice as described in aim 1. Since little is known about TULP proteins, discovering information regarding the function of TULP proteins should provide knowledge about the pathways involved in photoreceptor degeneration. It is possible that this work could form the foundation for future studies aimed at evaluating therapeutic modalities that might slow, stop, or reverse the course of retinal degeneration.