Biosynthesis and trafficking of phosphodiesterase in the retinal photoreceptors

项目摘要/摘要 我们研究的长期目标是研究翻译后蛋白质修饰的作用及其 在光信号转导蛋白合成和成熟中的作用。这项建议的目的是调查 磷酸二酯酶-6(PDE6)的异戊二烯基化在视网膜感光神经元中的重要性。PDE6是 一种对视觉至关重要的酶，它在人类中的缺失或突变会导致视网膜色素变性 (RP)和色盲。有趣的是，芳烃受体类蛋白-1(AIPL1)的变化是一种共同的疾病。 PDE6的伴侣会导致更严重的儿童期失明。尽管与几起致盲事件有明显联系 疾病，我们对光感受器神经元中这种关键酶的组装和成熟的知识是 不知道。我们的研究将特别关注AIPL1，HSP90和脂质修饰之间的相互作用。 PDE6的组装、成熟和运输到光感受器外节段。我们亦会研究 差异异戊二烯基化在光感受器细胞中介导光依赖信号的重要性。 我们将结合使用独特的动物模型，体内电生理测量，体外 视网膜培养模型和体外生化分析全面解决这一问题。 我们建议的研究与NEI的视网膜疾病计划保持一致，以“识别基因 与遗传性和视网膜退行性疾病(包括RP)有关，确定 这些突变背后的病理生理机制，并确定新的潜在治疗方法 治疗策略，如基因转移、组织和细胞移植、生长因子治疗以及 药物干预。“我们建议的研究具有临床意义，例如治疗 导致人类失明的PDE6和AIPL1突变。

PROJECT SUMMARY/ABSTRACT The long term goals of our research are to study the role of post-translational protein modifications and their role in phototransduction protein synthesis and maturation. The purpose of this proposal is to investigate the importance of the isoprenylation of phosphodiesterase-6 (PDE6) in retinal photoreceptor neurons. PDE6 is an enzyme that is essential for vision, and its absence or mutations in humans lead to retinitis pigmentosa (RP) and color blindness. Interestingly, changes in Aryl hydrocarbon receptor protein-like-1 (AIPL1), a co- chaperone for PDE6 leads to more severe childhood blindness. Despite the clear link to several blinding diseases, our knowledge on assembly and maturation of this essential enzyme in photoreceptor neurons is not known. Our study will specifically focus on the interplay between AIPL1, HSP90, and lipid modification in PDE6 assembly, maturation, and trafficking to the photoreceptor outer segments. We will also study the importance of differential isoprenylation in mediating light-dependent signaling in the photoreceptor cells. We will use a combination of unique animal models, in vivo electrophysiological measurements, ex vivo retinal culture models and in vitro biochemical analyses to comprehensively address this question. Our proposed studies are aligned with the Retinal Diseases Program of the NEI to “Identify the genes involved in both inherited and retinal degenerative diseases (including RP), determine the pathophysiological mechanisms underlying these mutations, and determine new potential therapeutic strategies for treatment such as gene transfer, tissue and cell transplantation, growth factor therapy, and pharmacological intervention.” Our proposed studies have clinical implications, such as therapy for mutations in PDE6 and AIPL1 that lead to blindness in humans.