Extracellular matrix remodeling in ocular anterior segment development

眼前节发育中的细胞外基质重塑

• 批准号: 8798380
• 负责人: SUNEEL S APTE
• 金额: $ 35.66万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8798380
• 关键词: ADAMTS9 gene; Accounting; Adhesions; Adult; Affect; Alleles; Anterior; Anterior eyeball segment structure; Back; Birth; Blindness; Brain; Candidate Disease Gene; Cardiac development; Cataract; Categories; Cell Lineage; Characteristics; Child; Childhood; Cleaved cell; Cleft Palate; Complex; Congenital Abnormality; Cornea; Corneal Opacity; Crystalline Lens; Cultured Cells; Data; Defect; Development; Ectoderm; Embryo; Endothelial Cells; Endothelium; Extracellular Matrix; Eye; Eye Abnormalities; Eye Development; Eye diseases; Fibronectins; Gene Mutation; Genes; Glaucoma; Glucosyltransferase; Goals; Human; Impairment; In Vitro; Infant; Inherited; Investigation; Irido-corneo-trabecular dysgenesis; Knowledge; Krause-Kivlin syndrome; Mass Spectrum Analysis; Mediating; Mesenchyme; Mesoderm; Messenger RNA; Metalloproteases; Modeling; Modification; Molecular; Morphogenesis; Mus; Mutagenesis; Mutate; Names; Neural Crest Cell; Optic Nerve; Outcome; Pathway interactions; Peptide Hydrolases; Phenotype; Prevention; Process; Proteins; Proteoglycan; Proteolysis; Public Health; Recombinants; Retina; Role; Site; Stimulus; Structure; Surface Ectoderm; Syndrome; Variant; Vascular Endothelium; Vesicle; Vision; Visual; congenital cataract; developmental disease; fibrillin-2; functional disability; lens; lens morphogenesis; malformation; novel; optic cup; pressure; prevent; public health relevance; relating to nervous system; versican

DESCRIPTION (provided by applicant): Anterior segment dysgenesis (ASD) encompasses a variety of developmental disorders of ocular anterior segment morphogenesis, a complex process involving several cell lineages and their associated extracellular matrix (ECM). The contribution of ECM remodeling to anterior segment morphogenesis has not been the subject of prior investigation. We recently discovered that loss of a single Adamts9 allele (encoding a secreted metalloprotease) resulted in Peters anomaly (corneal leukoma and persistent lens stalk) and lens defects, including cataract. ADAMTS9 is likely a major substrate for the glucosyltransferase B3GALTL, which is mutated in human Peters plus syndrome (PPS). In PPS, extraocular birth defects, including cleft palate and cardiac development anomalies, in which ADAMTS9 had been previously implicated, accompany Peters anomaly. We hypothesize that ADAMTS9 secreted by endothelial cells of the hyaloid vasculature and by the optic cup, is required for ECM turnover and could act non-autonomously on the lens and neural crest cells to regulate anterior segment morphogenesis. ADAMTS9 cleaves the proteoglycan, versican, about which little is known during eye development, despite its role in eye disease (Wagner syndrome). Also, preliminary studies support investigation of the ECM molecules, fibronectin and fibrillin-2 as potential ADAMTS9 substrates. In aim 1 of this proposal, we will comprehensively characterize ADAMTS9 modification by B3GALTL in vitro, and the consequences of preventing this modification in cultured cells. We will define the developmental, cellular and molecular changes underlying ASD resulting from Adamts9 haploinsufficiency. In aim 2, we will use a new floxed Adamts9 allele for conditional inactivation in vascular endothelium (Tie2-Cre), and optic cup (�re), to delineate how ADAMTS9 expressed by these specific lineages drives anterior segment morphogenesis. We will specifically investigate whether ADAMTS9 interacts with and proteolytically processes versican, fibronectin, and fibrillin-2, both in vitro and in the eye. Together, these aims provide a mechanistic continuum from B3GALTL to fundamentals of eye development to molecular actions of ADAMTS9. Relevance to public health: ADAMTS9 is a novel candidate gene for Peters anomaly, PPS or its variants, and other forms of human ASD and/or congenital cataract for which causative gene mutations are unknown. It will provide answers to a hitherto ignored question, i.e. how does ECM dynamics influence early eye development and what are the key proteases that modify the ECM? It will advance fundamental knowledge of ocular and lens morphogenesis that is highly relevant to ASD, childhood glaucoma and cataract, and provides mechanisms pertinent to the formation and possibly, the prevention of adult glaucoma and cataracts.

描述（由申请人提供）：眼前节发育不全（ASD）涵盖眼眼前节形态发生的多种发育障碍，这是一个涉及多种细胞谱系及其相关细胞外基质（ECM）的复杂过程。 ECM 重塑对眼前节形态发生的贡献尚未成为先前研究的主题。我们最近发现单个 Adamts9 等位基因（编码分泌型金属蛋白酶）的缺失会导致 Peters 异常（角膜白血病和持续性晶状体柄）和晶状体缺陷，包括白内障。 ADAMTS9 可能是葡萄糖基转移酶 B3GALTL 的主要底物，该酶在人类 Peters plus 综合征 (PPS) 中发生突变。在 PPS 中，Peters 异常伴随着眼外出生缺陷，包括腭裂和心脏发育异常，ADAMTS9 先前曾与这些缺陷有关。我们假设 ADAMTS9 由玻璃体血管内皮细胞和视杯分泌，是 ECM 周转所必需的，并且可以非自主地作用于晶状体和神经嵴细胞以调节眼前段形态发生。 ADAMTS9 可裂解蛋白多糖（多功能蛋白聚糖），尽管它在眼部疾病（瓦格纳综合征）中发挥作用，但在眼睛发育过程中人们对此知之甚少。此外，初步研究支持对 ECM 分子、纤连蛋白和 fibrillin-2 作为潜在 ADAMTS9 底物的研究。在本提案的目标 1 中，我们将在体外全面描述 B3GALTL 对 ADAMTS9 的修饰，以及在培养细胞中阻止这种修饰的后果。我们将定义 Adamts9 单倍体不足导致的自闭症谱系障碍 (ASD) 背后的发育、细胞和分子变化。在目标 2 中，我们将使用新的 floxed Adamts9 等位基因对血管内皮 (Tie2-Cre) 和视杯 (�re) 进行条件失活，以描述这些特定谱系表达的 ADAMTS9 如何驱动眼前节形态发生。我们将在体外和眼睛中专门研究 ADAMTS9 是否与多功能蛋白聚糖、纤连蛋白和原纤维蛋白-2 相互作用并进行蛋白水解处理。这些目标共同提供了从 B3GALTL 到眼睛发育基础再到 ADAMTS9 分子作用的机械连续体。与公共卫生的相关性：ADAMTS9 是 Peters 异常、PPS 或其变体以及其他形式的人类 ASD 和/或先天性白内障的新候选基因，其致病基因突变尚不清楚。它将为迄今为止被忽视的问题提供答案，即 ECM 动力学如何影响早期眼睛发育以及修改 ECM 的关键蛋白酶是什么？它将推进与 ASD、儿童青光眼和白内障高度相关的眼和晶状体形态发生的基础知识，并提供与成人青光眼和白内障的形成以及可能的预防相关的机制。