Ocular Dysgenesis in Agrin Transgenic Mice

Agrin 转基因小鼠的眼部发育不全

• 批准号: 7171836
• 负责人: Robert W Burgess
• 金额: $ 16.41万
• 依托单位: JACKSON LABORATORY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2007-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7171836
• 关键词: Affect; Agrin; Anophthalmos; Back; Biology; C57BL/6 Mouse; Characteristics; Chromosome Mapping; Class; Clinical; Cloning; Coloboma; Condition; Congenital Abnormality; Cornea; Corneal Opacity; Data; Defect; Development; Disruption; Employee Strikes; Environmental Risk Factor; Extracellular Matrix; Eye; Eye Abnormalities; Eye Development; Failure; Frequencies; Genes; Genetic; Genetic Techniques; Human; Inbred Strain; Incidence; Infiltration; Lead; Link; Localized; Maps; Mechanics; Microphthalmos; Modeling; Molecular; Molecular Genetics; Mouse Strains; Mus; Mutation; Penetrance; Personal Satisfaction; Phenotype; Pigments; Protein Overexpression; Proteins; Proteoglycan; Range; Rate; Reagent; Research; Retina; Role; Severities; Signal Transduction; Signaling Molecule; Site; Specificity; Structure; Study models; Susceptibility Gene; Testing; Tissues; Transgenes; Transgenic Mice; Transgenic Organisms; Work; base; biological adaptation to stress; gain of function; genetic manipulation; interest; lens; mouse model; neurodevelopment; novel; prenatal stress; research study; response; tool; transcription factor; transgene expression

DESCRIPTION (provided by applicant): Transgenic mice that over express the proteoglycan agrin have severe defects in ocular development. It is our hypothesis that this gain-of-function agrin mutation is perturbing eye development by disrupting the normal functions of the extracellular matrix (ECM) in the developing eye. The phenotype is also strain dependent, occurring only in a C57BL/6 genetic background, but with complete penetrance in that strain. Therefore, we also hypothesize that C57BL/6 mice provide a sensitized background for this phenotype, and that identifying the genes underlying this sensitivity will be relevant to related human conditions. The phenotype of the agrin-transgenic mice ranges from complete anophthalmia to corneal opacities caused by a failure of the lens to separate from the cornea. Frequently observed phenotypes include severe colobomas, a failure of lens to form, and an infiltration of pigmented fibrovascular tissue into the eye. The transgenic protein localizes to same structures that are affected. Based upon the localization of the transgenic protein and an increase in eye defects in a second, independent transgenic founder (though only at thirty percent initial penetrance) we conclude that the phenotype is a direct result of the presence of the transgenic protein in the eye. However, the possibilities that the phenotype is caused by a non-specific fetal stress response or by a mutation created by the transgene insertion have not been formally ruled out. The first specific aim of this proposal is to make this determination using a combination of genetic and molecular approaches. The phenotype is strain dependent and C57BL/6 mice are prone to spontaneous ocular defects at a rate of approximately five percent. The agrin-transgenic phenotypes resemble the severe extremes of the spontaneous defects. C57BL/6 provides a sensitized background for studying eye development, and the agrin-transgenic construct exacerbates this sensitivity. The second specific aim of this proposal is to use the agrin-transgenic mice in a classic genetic mapping experiment to identify the loci in the C57BL/6 background that predispose this strain to ocular dysgenesis. The haracterization of agrin overexpression as a tool for exploring the role of the ECM will open many new avenues of research. In addition, the identification of genes predisposing these transgenic mice to eye defects will be of great benefit to studies linking signaling molecules, environmental factors and protein effectors in both mice and humans.

描述（由申请人提供）：过度表达蛋白聚糖聚集蛋白的转基因小鼠在眼部发育方面存在严重缺陷。我们的假设是，这种功能获得性聚集蛋白突变通过破坏发育中眼睛的细胞外基质（ECM）的正常功能来扰乱眼睛发育。表型也是菌株依赖性的，仅发生在C57BL/6遗传背景中，但在该菌株中具有完全突变。 因此，我们还假设C57 BL/6小鼠为这种表型提供了致敏背景，并且鉴定这种敏感性的基因将与相关的人类条件相关。 聚集蛋白转基因小鼠的表型范围从完全无眼症到由透镜未能与角膜分离引起的角膜混浊。经常观察到的表型包括严重缺损、透镜形成失败和色素纤维血管组织浸润到眼中。转基因蛋白定位于受影响的相同结构。 基于转基因蛋白的定位和第二个独立转基因建立者中眼缺陷的增加（尽管仅在30%的初始转基因率下），我们得出结论，表型是眼中存在转基因蛋白的直接结果。然而，表型是由非特异性胎儿应激反应或由转基因插入产生的突变引起的可能性尚未被正式排除。本建议的第一个具体目标是使用遗传和分子方法相结合的方法进行确定。表型是品系依赖性的，C57 BL/6小鼠易于自发性眼缺陷，发生率约为5%。聚集蛋白转基因表型类似于自发缺陷的严重极端。C57 BL/6为研究眼发育提供了一个敏感的背景，而聚集蛋白转基因构建体加剧了这种敏感性。该建议的第二个具体目的是在经典的遗传作图实验中使用聚集蛋白转基因小鼠，以鉴定C57 BL/6背景中使该品系易患眼发育不全的基因座。将聚集蛋白过表达的特征化作为探索ECM作用的工具将开辟许多新的研究途径。此外，鉴定使这些转基因小鼠易患眼缺陷的基因将对小鼠和人类中连接信号分子、环境因素和蛋白质效应物的研究非常有益。