Characterization of DHDDS RP59 Knockin Models of Retinitis Pigmentosa

项目摘要/摘要 视网膜色素性视网膜病变(RP)是一组引起视网膜变性的异质性疾病。到目前为止， 超过58个基因的突变与经典的视网膜色素变性有关，所有形式的 遗传性视网膜营养不良至少涉及300个基因。我的研究重点是视网膜色素变性-59 (RP59)，一种非综合征性常染色体隐性形式的RP，由脱氢胞苷突变引起 二磷酸合成酶(DHDDS)基因，定位于染色体1p36.11的外显子3。最流行的 突变为K42E，T206A和R98W也已被报道。我们产生了小鼠DHDDS K42E敲门声- 在小鼠模型中采用CRISPR/Cas9基因编辑技术。初步数据显示， ERG b波的波幅，我们已经报道了显著的GFAP上调，没有视网膜变性或 蛋白质N-糖基化减少。这表明有缺陷的DHDDS依赖型视网膜变性可能是 比简单的蛋白质糖基化引起的功能丧失机制要复杂得多。为了更好地 了解与RP59突变相关的选择性视网膜病理的基础，我们计划表征 DhddsK42E/K42E敲入小鼠的解剖学和生理学研究。此外，我们还将创建和分析两个新的 DHDDS相关遗传性视网膜疾病模型，DHDDS T206A/T206A和DhddsT206A/K42E。对视网膜的研究 这些小鼠模型将使我们深入了解这种遗传性疾病的病理生理学，并可能导致新的 这种疾病的治疗选择。

Project Summary/Abstract Retinitis pigmentosa (RP) is a heterogeneous group of disorders that cause retinal degeneration. To date, mutations in more than 58 genes have been linked to classic retinitis pigmentosa, and collectively all forms of inherited retinal dystrophies involves at least 300 genes. My studies are focused on retinitis pigmentosa-59 (RP59), a non-syndromic autosomal recessive form of RP caused by mutations in the dehydrodolichyl diphosphate synthase (DHDDS) gene, localized to exon 3 on chromosome 1p36.11. The most prevalent mutation is K42E, while T206A and R98W also have been reported. We generated a murine Dhdds K42E knock- in mouse model using CRISPR/Cas9 gene editing technology. Preliminary data shows significant reduction of ERG b-wave amplitudes and we have reported marked GFAP up-regulation, without retinal degeneration or decreased protein N-glycosylation. This suggests that defective DHDDS-dependent retinal degeneration may be more complicated than simply a loss-of-function mechanism due to altered protein glycosylation. To better understand the basis for selective retinal pathology associated with RP59 mutations, we plan to characterize the DhddsK42E/K42E knock-in mouse anatomically and physiologically. Additionally, we will create and analyze two new models of DHDDS-related inherited retinal disease, Dhdds T206A/T206A and DhddsT206A/K42E. Studying the retina in these mouse models will give us insight into the pathophysiology of this inherited disorder, and may lead to novel treatment options for this disorder.