Functional Analysis of Novel Genes in Eye Development and Vision

1：血小板衍生生长因子D(PDGFD)属于PDGF/VEGF家族。PDGFD在晶状体生长调控中起关键作用，反义PDGFD能强烈抑制晶状体上皮细胞的增殖，提示PDGFD在眼组织协调生长机制中具有重要的体内作用。PDGFD在光感受器中也有表达，在突触末端有明显的定位。已经确定了PDGFD基因的功能启动子，并正确地将GFP报告基因的表达定向到眼睛组织。小鼠PDGFD基因的条件性敲除已接近完成。 2：Lengsin是谷氨酰胺合成酶(GS)超家族中的一个新成员，该超家族是脊椎动物眼晶状体特有的。Lengsin在终末分化的次级纤维细胞层中特异表达，在该层中，细胞核和其他细胞器丢失，细胞骨架和细胞内连接重新组织。Y2H实验表明，长度蛋白作为晶状体主要细胞骨架成分的伴侣，参与了终末分化过程中细胞成分的重组。目前，长度蛋白的敲除模型已经完成并正在研究中。 补体因子H(CFH)在老年性黄斑变性(AMD)的发生发展中起重要作用。利用老年人RPE/脉络膜和视网膜的酵母双杂交文库和CFH的AMD相关结构域7的诱饵构建物，我们已经确定了人RPE/脉络膜中潜在的CFH结合的重要靶点。这些结果已经通过免疫荧光定位得到证实，并对AMD的进展进行干预具有一定的意义。 4：Retbindin是一种新的视网膜蛋白。我们创造了转基因小鼠来过度表达人类视黄醇结合蛋白。使用定制的cDNA微阵列对这些进行了分析。结果表明，视黄醇结合素可能在光感受器的功能和活性中起作用。

1: Platelet-derived growth factor D (PDGFD) belongs to the PDGF/VEGF family. PDGFD has a key role in control of lens growth and anti-PDGFD strongly inhibits lens epithelial cell proliferation This finding suggests a major in vivo role for PDGFD in the mechanisms of coordinated growth of eye tissues. PDGFD is also expressed in photoreceptors with striking localization in the synaptic ends. A functional promoter of the PDGFD gene has been identified and correctly directs expression of a GFP reporter to eye tissues. A conditional knock out of PDGFD in mouse is nearing completion. 2: Lengsin is a novel member of the glutamine synthetase (GS) superfamily that is specific for the vertebrate eye lens. Lengsin is expressed specifically in the layer of terminally differentiating secondary fiber cells in which nuclei and other organelles are lost and cytoskeleton and intracellular junctions are reorganized. Y2H experiments suggest that lengsin has a role as a chaperone of major cytoskeletal components of the lens and participates in the reorganization of cellular components in terminla differentiation.A knock out model of lengsin is now completed and is being examined. 3: Complement factor H (CFH) has an important role in the development of age-related macular degeneration (AMD). Using yeast 2-hybrid libraries for aged human RPE/choroid and retina and bait constructs for the AMD-related domain 7 of CFH we have identified potentially important targets for CFH binding in human RPE/choroid. These results have been confirmed by immunofluorescence localization and have implications for intervention in the progression of AMD. 4: Retbindin is a novel protein of the retina. We created transgenic mice to overexpress human retbindin. These have been analyzed using custom cDNA microarrays. Results suggest that retbindin may have a role in photoreceptor function and activity.