MEMBRANE BIOSYNTHESIS IN NORMAL AND DYSTROPHIC RETINAS

描述(改编自申请人的摘要)：首席调查员 寻求将可导致人类视网膜变性的突变与 视紫红质生物合成/转运障碍与感光细胞死亡。许多 人类视网膜退化涉及仅在视杆细胞中表达的突变基因，但 球果就会死亡。杆状物的损伤如何导致锥体死亡尚不清楚。具体的 本研究的目的是：(1)开发转基因非洲爪哇作为一种 模型系统确定干扰视紫红质合成和 运输和(2)建立转基因非洲爪猴视网膜变性模型 允许评估棒材死亡对圆锥体的影响 生死存亡。为此，调查员将确定：(1)在哪里 转基因产物定位于光感受器细胞内；(2) 外节段生物合成和运输中的转基因产物 膜蛋白；(3)它们对光感受器细胞活力的影响。 使用视蛋白启动子驱动已经获得了初步结果 绿色荧光蛋白(GFP)及其融合蛋白的表达。这个 转基因产物仅在主杆中表达，并可检测到5 受精后几天，活着的蝌蚪的眼睛里。自从青蛙 视网膜富含视锥，这些转基因青蛙适合检查 死亡视杆与相邻视锥细胞相互作用的人体模型 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.