Cone survival despite rod degeneration in XOPS-mCFP transgenic zebrafish
Cone survival despite rod degeneration in XOPS-mCFP transgenic zebrafish
复制标题
DOI：
10.1167/iovs.05-0797
复制
发表时间：
2005-12-01
影响因子：
4.4
通讯作者：
Fadool, JM
中科院分区：
文献类型：
--
作者：
Morris, AC;Schroeter, EH;Fadool, JM
目的。在视网膜色素变性的动物模型中，视杆感光细胞的退化最终导致视锥细胞感光细胞的丧失。本研究的目的是建立斑马鱼视紫红质启动子驱动的转基因斑马鱼杆状变性模型。方法通过注射获得XOPS-mCFP转基因斑马鱼。用免疫组织化学方法检测幼体和成体视网膜的细胞类型、增殖和TUNEL标记。RT-PCR检测视杆细胞和视锥细胞特异性转录本。结果受精后55h，XOPS启动子引导mCFP在视杆细胞中特异性表达。XOPS-mCFP杂合子的杆状突起在受精后3.5天开始死亡，到受精后5天几乎完全消失。在视网膜边缘观察到少量杆状突起，在转基因成体的外核层(ONL)内观察到大量未成熟突起。转基因幼体和成体ONL细胞的凋亡率增加，成体的视杆前体细胞增殖增加。ERG分析证实，该品系不存在杆状反应。结论：XOPS-mCFP转基因动物在7个月龄时，视锥细胞形态和电生理均正常。结论：XOPS-mCFP转基因可导致视锥细胞选择性变性，而不发生继发性视锥细胞丢失。这就提出了关于斑马鱼视杆-视锥相互作用的重要性以及它们作为人类遗传性视网膜退化模型的潜力的重要问题。
PURPOSE. In animal models of retinitis pigmentosa, rod photoreceptor degeneration eventually leads to loss of cone photoreceptors. The purpose of this study was to characterize a transgenic model of rod degeneration in zebrafish.METHODS. Zebrafish transgenic for XOPS-mCFP, a membrane-targeted form of cyan fluorescent protein driven by the Xenopus rhodopsin promoter, were generated by plasmid injection. Immunohistochemistry was used to detect cell type, proliferation, and TUNEL markers in larval and adult retinas. Rod- and cone-specific transcripts were detected by RT-PCR. Visual responses in transgenic adults were measured by electroretinogram.RESULTS. The XOPS promoter directed specific expression of mCFP in rods by 55 hours post fertilization (hpf). Rods in XOPS-mCFP heterozygotes began dying at 3.5 days post fertilization (dpf) and were almost completely absent by 5 dpf. A few rods were observed at the retinal margin, and numerous immature rods were observed in the outer nuclear layer (ONL) of transgenic adults. Apoptosis was increased in the ONL of larval and adult transgenic animals, and an elevation of rod precursor proliferation in adults was observed. ERG analysis confirmed that rod responses were absent in this line. Cone morphology and electrophysiology appeared normal in transgenic animals up to 7 months of age.CONCLUSIONS. The XOPS-mCFP transgene causes selective degeneration of rods without secondary loss of cones in animals up to 7 months of age. This raises important questions about the significance of rod-cone interactions in zebrafish and their potential as a model of human inherited retinal degenerations.