MEMBRANE BIOSYNTHESIS IN NORMAL AND DYSTROPHIC RETINAS

描述（改编自申请人摘要）：主要研究者 试图将可能导致人类视网膜变性的突变与 视紫红质生物合成/转运紊乱和感光细胞死亡。许多 人类视网膜变性涉及仅在杆中表达的突变基因，然而 锥细胞死亡。视杆细胞损伤如何导致视锥细胞死亡尚不清楚。具体 本申请的目的是：（1）开发转基因非洲爪蟾， 模型系统，以确定干扰视紫红质合成的因素， 运输和（2）建立转基因非洲爪蟾视网膜变性模型 允许评估棒死亡对锥体的影响 生存为了做到这一点，研究人员将确定：（1） 转基因产物定位于感光细胞内;（2） 转基因产物对外节生物合成和转运的影响 膜蛋白;和（3）它们对感光细胞活力的影响。 利用视蛋白启动子驱动 表达绿色荧光蛋白（GFP）和GFP融合蛋白。的 转基因产物仅在主要视杆中表达，并且是可检测的5 在受精后的几天，在活着的蝌蚪的眼睛里。自从青蛙 视网膜是锥丰富，这些转基因青蛙是适合检查 作为人类模型的死亡杆和邻近锥体的相互作用 视网膜色素变性

DESCRIPTION (adapted from the applicant's abstract): The principal investigator seeks to link mutations that can induce retinal degeneration in humans with disordered rhodopsin biosynthesis/transport and photoreceptor cell death. Many human retinal degenerations involve mutant genes expressed only in rods, yet cones die. How the injury of rods leads to cone death is unclear. The specific aims of this application are to: (1) develop transgenic Xenopus laevis as a model system to determine factors that perturb rhodopsin synthesis and transport and (2) develop models of retinal degeneration in transgenic Xenopus laevis to permit assessment of the impact of the death of rods on cone survival. To accomplish this, the investigator will determine: (1) where the transgene products are localized within photoreceptor cells; (2) the effect of the transgene products on the biosynthesis and transport of outer segment membrane proteins; and (3) their impact on photoreceptor cell viability. Preliminary results have been obtained using the opsin promoter to drive expression of green fluorescent protein (GFP) and GFP fusion proteins. The transgene products are expressed only in the major rods and are detectable 5 days after fertilization in the eye of the living tadpole. Since the frog retina is cone-rich, these transgenic frogs are suitable for examining the interaction of dying rods and the neighboring cones as models of human retinitis pigmentosa.