Mechanisms of development of curved refractive surfaces

弯曲折射表面的发展机制

• 批准号: 10443019
• 负责人: Jessica E Treisman
• 金额: $ 41万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-01 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10443019
• 关键词: Adult; Animal Model; Apical; Area; Astigmatism; Biological Models; Biology; CCAAT-Enhancer-Binding Proteins; Cells; Characteristics; Cornea; Corneal dystrophy; Crystallins; Data; Defect; Development; Disease; Drosophila genus; Ecdysone; Epithelial Cells; Extracellular Matrix; Eye; Genes; Genetic Models; Genetic Transcription; Homologous Gene; Hormonal; Human; Human Development; Hyperopia; Insecta; Keratoconus; Lens development; Light; Mediating; Modeling; Molecular; Mus; Mutate; Mutation; Myopia; Organ; Organoids; PRDM1 gene; Pattern; Peripheral; Phenotype; Photoreceptors; Pigments; Process; Property; Proteins; Radial; Regulation; Repression; Retina; Retinal Cone; Role; Shapes; Source; Structure; Surface; System; Testing; Tissues; Transcriptional Regulation; Transforming Growth Factor beta; Up-Regulation; Vision Disorders; Visual; base; corneal epithelium; experimental study; extracellular; fly; insight; lens; limbal; mouse development; mutant; overexpression; protein expression; stem cells; steroid hormone; transcription factor

Abnormal curvature of the cornea is associated with multiple visual defects including myopia, hyperopia, keratoconus and astigmatism. However, the developmental mechanisms that generate appropriate corneal curvature are not well understood. This proposal will use the Drosophila corneal lens as a simple model system to investigate the development of curvature, and will test whether it shares common molecular and developmental mechanisms with the mammalian cornea. The project is based on data showing that the conserved Blimp-1 transcription factor is essential for external curvature of the Drosophila corneal lens, and that it acts in the peripheral secondary and tertiary pigment cells rather than in the central cells that secrete the bulk of the extracellular corneal lens material. The possibility of an analogous function for mouse Blimp1/Prdm1 is suggested by its enrichment in the limbal epithelial cells at the periphery of the adult cornea. The first aim will investigate the transcriptional network that controls Drosophila corneal lens development. In the absence of Blimp-1, the C/EBP homologue Slow border cells (Slbo) is highly upregulated, and Slbo overexpression, like loss of Blimp-1, results in externally flat corneal lenses. The hypothesis that slbo repression is a major function of Blimp-1 will be tested by inactivating both genes simultaneously. This aim will also identify other critical transcription factors downstream of Blimp-1, and will test whether transient hormonally regulated expression of Blimp-1 in the eye is important for the temporal control of differentiation. The second aim will determine how the peripheral pigment cells contribute to corneal lens curvature. Two possibilities will be investigated: that pigment cells secrete protein components that localize to the peripheral corneal lens and give it structural properties distinct from the central region, and that force exerted on the corneal lens through its attachments to pigment cells controls the pattern of curvature. The third aim will explore possible conservation between insect and mammalian corneal structures. CG43333, a gene that is repressed by Blimp-1 in the Drosophila retina and contributes to the abnormal corneal lens phenotype of Blimp-1 mutants, is homologous to Transforming growth factor beta- induced protein, a frequent target of mutation in human corneal dystrophies. The effect of disease mutations on CG43333 accumulation and localization will be examined to determine whether they reproduce features of corneal dystrophy. Human corneal epithelial cells and corneal organoids will be used to establish whether human BLIMP1 has target genes in common with Drosophila Blimp-1 in the cornea. Finally, the developmental expression pattern of Blimp1 in the mouse cornea will be examined to determine whether it is consistent with a role in corneal curvature. These experiments will elucidate how curvature is imparted to refractive structures composed primarily of extracellular matrix, and will establish the Drosophila corneal lens as a model to understand corneal development and disease.

角膜的异常曲率与包括近视在内的多种视觉缺陷有关， 超副局，角膜骨膜和散光。但是，产生的发展机制 适当的角膜曲率尚不清楚。该建议将使用果蝇角膜镜头 一个简单的模型系统来研究曲率的发展，并将测试它是否共享 哺乳动物角膜的分子和发育机制。该项目基于数据 表明保守的Blimp-1转录因子对于果蝇的外部曲率至关重要 角膜透镜，并作用于外围次级和三级色素细胞，而不是中央 分泌大部分细胞外角膜透镜材料的细胞。类似功能的可能性 对于小鼠blimp1/prdm1，它是由于其在外围的边缘上皮细胞中的富集而提出的 成人角膜。第一个目标将研究控制果蝇角膜镜头的转录网络 发展。在没有Blimp-1的情况下，C/EBP同源物慢边界细胞（SLBO）高度 上调和SLBO的过表达（例如失去苗条）会导致外部平坦的角膜透镜。这 假设SLBO抑制是Blimp-1的主要功能，将通过灭活两个基因来测试 同时地。该目标还将确定Blimp-1下游的其他关键转录因子，并将 测试瞬时荷尔蒙调节在眼睛中的表达是否对颞叶很重要 控制分化。第二个目标将决定周围色素细胞如何贡献 角膜透镜曲率。将研究两种可能性：色素细胞分泌蛋白质成分 该位置到周围角膜镜头，并赋予其与中央区域不同的结构特性， 而这种力通过其与色素细胞的附着在角膜镜上施加的力，控制了 曲率。第三个目标将探索昆虫和哺乳动物角膜之间可能的保护 结构。 CG43333，一种在果蝇视网膜中被Blimp-1抑制的基因，并有助于该基因 Blimp-1突变体的异常角膜透镜表型与转化生长因子β- 诱导蛋白质，这是人角膜营养不良中突变的常见靶标。疾病突变的影响 在CG43333上将检查积累和本地化，以确定它们是否重现特征 角膜营养不良。人角膜上皮细胞和角膜器官将用于确定是否是否 Human Blimp1具有角膜中果蝇Blimp-1共同的靶基因。最后， 将检查小鼠角膜中Blimp1的发育表达模式，以确定是否 与在角膜曲率中的作用一致。这些实验将阐明曲率如何赋予 主要由细胞外基质组成的折射结构，将建立果蝇角膜 镜头是了解角膜发育和疾病的模型。