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：
7505648
负责人：
DEBASISH SINHA
金额：
$ 41万
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/7505648
关键词：
1-Phosphatidylinositol 3-Kinase Address Affect Amino Acids Animal Model Appendix 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 Closure Coculture Techniques Condition Confocal Microscopy Crystallins Culture Media Data Development Disease Disease regression 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 Public Health Publishing Rat-1 Rattus Recurrence Reporting Retina Retinal Diseases Role Sprague-Dawley Rats Stimulus Structure Surface Tandem Repeat Sequences Techniques Testing Therapeutic Thinking 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 intracellular protein transport lens lens protein migration mouse model mutant nestin protein novel prevent protein localization location research study response size time use 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）：持续的胎儿脉管系统（PFV）是一种人类疾病，是由于胎儿脉管系统失败而导致的。这是在原本正常的孩子中发现的一种常见的先天性发育障碍。 PFV疾病的根本原因尚不清楚。我们先前描述了Sprague-Dawley大鼠中的天然突变（NUC1），其新型眼表型涉及白内障，胎儿脉管系统的保留和视网膜的发育异常。在NUC1中，正如PFV的其他几种小鼠模型中报道的那样，整个胎儿血管的消退失败，而不仅仅是其中的一部分。我们最近报道说，引起NUC1的突变是大鼠染色体10上2A3/A1-晶状体基因的外显子6中的27个基对插入。27个基对插入由7个基本对序列的接近完美的串联重复序列组成，是7碱基对序列的接近完美的串联序列， tgactat。这种框内插入导致外显子6中普遍保守的甘氨酸残基的丧失，并用10个新的氨基酸替换。我们证明，在神经视网膜中，仅在星形胶质细胞中表达2A3/A1-晶状体。在NUC1大鼠中，星形胶质细胞围绕着保留的血管，如其他PFV动物模型所示。但是，星形胶质细胞与正常眼中的透明脉管系统无关。尽管2a3/a1-晶状蛋白完全是晶状体的细胞质，但蛋白质在星形胶质细胞中主要是核的。来自NUC1纯合子的晶状体纤维和星形胶质细胞都表现出惊人的结构异常，对中间丝（IFS）的表达和组织产生深远影响。我们已经证明，与胎儿脉管系统相关的星形胶质细胞和NUC1大鼠和PFV患者中的镜头都会表现出增加的VEGF量。基于这些发现，我们假设2A3/A1-晶体的突变导致星形胶质细胞与透明动脉的异常关联，这抑制了胎儿脉管系统的回归。为了检验这一假设，提出了以下特定目的：AIM1：在晶状体纤维细胞和星形胶质细胞发育过程中表征和比较野生型和NUC1纯合大鼠中2A3/A1-晶状蛋白的表达。 AIM2：调查发育过程中NUC1纯合星形胶质细胞的运动能力是否改变有助于星形胶质细胞与透明脉管系统之间的异常关联。 AIM3：确定表达突变体2A3/A1-晶状蛋白的星形胶质细胞产生的VEGF是否会介导Nuc1大鼠中透明脉管系统的存活和稳定。我们认为，拟议的研究应为调节透明血管回归的细胞和分子相互作用提供新的见解。 2A3/A1-晶状体可能在透明血管回归中起作用的可能性很重要。它可能有助于阐明具有潜在临床意义的PFV的基础机制。公共卫生相关性：持续的胎儿脉管系统（PFV）是一种常见的盲目，先天性眼科疾病。我们的数据（发表和未发表）表明，突变体2A3/A1-晶状体在PFV中起作用。拟议的研究可能有助于阐明PFV的基础机制，这些机制将具有潜在的治疗意义。