A novel bA3/A1-crystallin gene mutation results in persistent fetal vasculature

一种新的 bA3/A1-晶状体蛋白基因突变导致胎儿血管系统持续存在

基本信息

批准号：
7888266
负责人：
DEBASISH SINHA
金额：
$ 40.59万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-01 至 2012-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7888266
关键词：
1-Phosphatidylinositol 3-Kinase Address Affect Amino Acids Animal Model Arteries Astrocytes Base Pairing Binding Biological Assay Birth Blood Vessels Blood capillaries Cataract Cell Survival Cell physiology Cells Chemotaxis Child Chromosomes, Human, Pair 10 Chronic Clinical Coculture Techniques Confocal Microscopy Crystallins Culture Media Data Development Disease Employee Strikes Endothelial Cells Endothelium Enzyme-Linked Immunosorbent Assay Exhibits Exons Extracellular Signal Regulated Kinases Eye Eye Abnormalities Failure Gene Mutation Genes Glial Fibrillary Acidic Protein Glycine Hemorrhage Heterozygote Homozygote Hour Human Immigration Immunohistochemistry In Situ Hybridization Intermediate Filaments Lens Fiber MAPK3 gene Measures Mediating Membrane Mitogen Activated Protein Kinase 1 Mitogen-Activated Protein Kinase Kinases Mitogen-Activated Protein Kinases Modeling Molecular Mutation Neural Retina Nuclear Pathway interactions Patients Pericytes Phenotype Phosphatidylinositols Phosphotransferases Photography Platelet-Derived Growth Factor Play Protein Kinase Proteins Publishing Rat-1 Rattus Recurrence Reporting Retina Retinal Diseases Role Sprague-Dawley Rats Stimulus Structure Surface Tandem Repeat Sequences Techniques Testing Therapeutic Threonine Touch sensation Tube Up-Regulation Uveitis Vascular Endothelial Growth Factors Vascular System Vimentin Vitreous humor Western Blotting Yeasts aqueous base capillary cell motility developmental disease fetal fiber cell human disease insight lens lens protein migration mouse model mutant nestin protein novel prevent public health relevance research study response time use vessel regression yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): Persistent fetal vasculature (PFV) is a human disease that results from a failure of the fetal vasculature to regress. It is a common congenital developmental disorder of the eye found in an otherwise normal child. The underlying cause of PFV disease is not well understood. We previously described a naturally occurring mutation (Nuc1) in the Sprague-Dawley rat with a novel eye phenotype involving cataract, retention of fetal vasculature, and developmental abnormalities in the retina. In Nuc1 there is failure of regression of the entire fetal intraocular vasculature and not just part of it, as reported in several other mouse models of PFV. We recently reported that the mutation causing Nuc1 is a 27 base pair insertion in exon 6 of the 2A3/A1-crystallin gene on rat chromosome 10. The 27 base pair insertion is composed of near-perfect tandem repeats of a 7 base pair sequence, TGACTAT. This in-frame insertion results in the loss of a universally conserved glycine residue in exon 6 and its replacement with 10 new amino acids. We demonstrated that in the neural retina, 2A3/A1-crystallin is expressed only in the astrocyes. In the Nuc1 rat, astrocytes surround the retained vessels as is found in other animal models of PFV. However, astrocytes are not associated with the hyaloid vasculature in the normal eye. While 2A3/A1-crystallin is entirely cytoplasmic in lens, the protein is largely nuclear in astrocytes. Both lens fibers and astrocytes from Nuc1 homozygotes show striking structural abnormalities with profound effects on the expression and organization of intermediate filaments (IFs). We have demonstrated that both the astrocytes associated with the fetal vasculature and the lenses in Nuc1 rats and PFV patients express increased amounts of VEGF. Based on these findings, we hypothesize that mutation of 2A3/A1- crystallin causes abnormal association of astrocytes with the hyaloid artery, which inhibits regression of the fetal vasculature. To test this hypothesis, the following specific aims are proposed: AIM1: To characterize and compare 2A3/A1-crystallin expression in wildtype and in Nuc1 homozygous rats during lens fiber cell and astrocyte development. AIM2: To investigate if altered motility of Nuc1 homozygous astrocytes during development contributes to the abnormal association between astrocytes and the hyaloid vasculature. AIM3: To determine if VEGF produced by astrocytes expressing mutant 2A3/A1-crystallin mediates the survival and stabilization of the hyaloid vasculature in the Nuc1 rat. We believe that the proposed studies should provide new insights into the cellular and molecular interactions that regulate hyaloid vascular regression. The possibility that 2A3/A1-crystallin may have a role in hyaloid vascular regression is important; it may help elucidate mechanisms underlying PFV that would have potential clinical implications. PUBLIC HEALTH RELEVANCE: Persistent Fetal Vasculature (PFV) is a common blinding, congenital eye disease. Our data (published and unpublished) indicate that mutant 2A3/A1-crystallin plays a role in PFV. The proposed studies may help elucidate mechanisms underlying PFV that would have potential therapeutic implications.

描述（由申请人提供）：持续性胎儿脉管系统（PFV）是一种因胎儿脉管系统无法消退而导致的人类疾病。这是一种常见的先天性眼睛发育障碍，常见于正常儿童。 PFV 疾病的根本原因尚不清楚。我们之前描述了 Sprague-Dawley 大鼠中自然发生的突变 (Nuc1)，该突变具有新的眼睛表型，涉及白内障、胎儿脉管系统保留和视网膜发育异常。在 Nuc1 中，整个胎儿眼内血管系统（而不仅仅是其中一部分）无法消退，正如其他几种 PFV 小鼠模型所报道的那样。我们最近报道，引起Nuc1的突变是大鼠10号染色体上2A3/A1-晶状体蛋白基因的外显子6中的27个碱基对插入。27个碱基对插入由7个碱基对序列的近乎完美的串联重复组成， TGACTAT。这种框内插入导致外显子 6 中普遍保守的甘氨酸残基丢失，并被 10 个新氨基酸取代。我们证明，在神经视网膜中，2A3/A1-晶状体蛋白仅在星形胶质细胞中表达。在 Nuc1 大鼠中，星形胶质细胞围绕着保留的血管，就像在其他 PFV 动物模型中发现的那样。然而，星形胶质细胞与正常眼中的玻璃体脉管系统无关。虽然 2A3/A1-晶状体蛋白在晶状体中完全是细胞质，但该蛋白在星形胶质细胞中主要是细胞核。 Nuc1 纯合子的晶状体纤维和星形胶质细胞均表现出显着的结构异常，对中间丝 (IF) 的表达和组织产生深远影响。我们已经证明，Nuc1 大鼠和 PFV 患者中与胎儿脉管系统和晶状体相关的星形胶质细胞表达的 VEGF 量增加。基于这些发现，我们假设 2A3/A1- 晶状体蛋白的突变导致星形胶质细胞与玻璃体动脉的异常关联，从而抑制胎儿脉管系统的退化。为了检验这一假设，提出了以下具体目标： AIM1：表征和比较野生型和 Nuc1 纯合大鼠在晶状体纤维细胞和星形胶质细胞发育过程中 2A3/A1-晶状体蛋白的表达。目标 2：研究 Nuc1 纯合星形胶质细胞在发育过程中运动性的改变是否会导致星形胶质细胞与玻璃体脉管系统之间的异常关联。 AIM3：确定表达突变体 2A3/A1-晶状体蛋白的星形胶质细胞产生的 VEGF 是否介导 Nuc1 大鼠中玻璃体脉管系统的存活和稳定。我们相信，拟议的研究应该为调节玻璃体血管退化的细胞和分子相互作用提供新的见解。 2A3/A1-晶状体蛋白可能在玻璃体血管退化中发挥作用的可能性很重要；它可能有助于阐明 PFV 的潜在机制，并具有潜在的临床意义。公众健康相关性：持续性胎儿血管系统 (PFV) 是一种常见的致盲性先天性眼病。我们的数据（已发表和未发表）表明突变体 2A3/A1-crystallin 在 PFV 中发挥作用。拟议的研究可能有助于阐明 PFV 的潜在机制，这可能具有潜在的治疗意义。