权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Alk1 regulation of embryonic angiogenesis

Alk1 调控胚胎血管生成

基本信息

批准号：
7781387
负责人：
BETH L ROMAN
金额：
$ 35.2万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2005
资助国家：
美国
起止时间：
2005-04-01 至 2012-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7781387
关键词：
Activin Receptor Address Age of Onset Architecture Basement membrane Blood Vessels Blood flow Cell Culture Techniques Cephalic Complex Conflict (Psychology)Cultured Cells Data Development Dominant-Negative Mutation Dysplasia Embryo Embryonic Development Endothelial Cells Endothelium Exhibits Gene Expression Profile Genes Genetic Epistasis Goals Heart Hereditary hemorrhagic telangiectasia Homeostasis Human Laboratories Lesion Ligands Ligature Literature Mammalian Cell Maps Mechanics Mediating Messenger RNA Microarray Analysis Modeling Molecular Mus Mutate Mutation Nature Outcome Pathogenesis Pathway interactions Patients Pattern Pharmaceutical Preparations Phenotype Physiological Play Receptor Activation Receptor Signaling Regulation Research Personnel Resolution Role Sheep Siblings Signal Pathway Signal Transduction TGFB1 gene Techniques Telangiectasis Testing Time Transcript Translating Vascular Diseases Vascular remodeling Viola Zebrafish angiogenesis base cis acting element design experience in vivo insight knock-down malformation migration mutant novel overexpression positional cloning programs receptor research study response shear stress stem tool

项目摘要

DESCRIPTION (provided by applicant): Homozygous inactivation of the endothelial-specific TGFB type I receptor, Alk1, results in embryonic lethality stemming from vascular malformations, and heterozygous inactivation results in a potentially lethal human vascular dysplasia, hereditary hemorrhagic telangiectasia type 2 (HHT2). Clearly, AIk1 plays a necessary role in building and maintaining the vertebrate vasculature; however, the nature of that role is currently unclear. The objective of this proposal is to use the accessible zebrafish embryo, which has a well described, stereotypical vertebrate vasculature, to define the effects of Alkl activation on endothelial cell functional state and transcript expression. Specific Aim 1 comprises experiments designed to test the hypothesis that TGFB signaling through Alk1 is required for angiogenic resolution. Studies in support of this Aim will include time lapse confocal analysis of endothelial sprouting and proliferation in violet beauregarde (vbg) mutants, which harbor a mutation in alk1; and assessment of endothelial migration, proliferation, sprouting, and basement membrane formation in zebrafish embryos overexpressing dominant negative and/or constitutively active forms of alk1, alk5 (the canonical TGFB type I receptor that reportedly competes with Alk1 in determining endothelial state), and tgfB within the endothelium. Specific Aim 2 comprises experiments designed to test the hypothesis that Alk1 is induced by shear stress and plays a role in vascular remodeling. The effect of blood flow on alk1 expression and remodeling of cranial vessels in zebrafish embryos will be determined, and the effect of shear stress on Alk1expression in cultured mammalian cells will be assessed. Further experiments will identify molecular components of the pathway that translates mechanical shear stress into Alk1 induction. Specific Aim 3 comprises experiments designed to identify downstream components of Alk1 signaling. Expression levels of genes reportedly regulated by constitutively active Alk1 in mammalian cell culture will be compared in vbg mutants and wild type siblings, and novel alkl-regulated genes will be sought by comparing the endothelial transcriptome in vbg mutants and wild type siblings. Taken together, the proposed experiments will determine whether Alk1 plays a role in angiogenic activation, resolution, and/or remodeling, and, with the definition of downstream targets, will promote a better understanding of the molecular pathways of normal vessel development and HHT2 pathogenesis.

描述(申请人提供)：血管内皮细胞特异性TGFb I型受体Alk1的纯合子失活会导致血管畸形引起的胚胎死亡，杂合子失活会导致潜在的致命性人类血管发育不良，遗传性出血性毛细血管扩张症2型(HHT2)。显然，AIk1在建立和维持脊椎动物的血管系统中起着必要的作用；然而，该作用的性质目前尚不清楚。这项建议的目的是利用可接近的斑马鱼胚胎，它具有良好的描述，刻板的脊椎动物血管系统，以确定ALK1激活对内皮细胞功能状态和转录表达的影响。特定目的1包括旨在测试TGFb通过Alk1信号是血管生成解析所必需的假设的实验。支持这一目标的研究将包括：对紫罗兰色博雷加德(VBG)突变体的内皮细胞萌发和增殖的时移共聚焦分析；以及评估斑马鱼胚胎中内皮细胞的迁移、增殖、萌发和基底膜的形成；过度表达Alk1、Alk5(据报道在决定内皮状态方面与Alk1竞争的经典的TGFbI型受体)和TGFb的斑马鱼胚胎中的内皮迁移、增殖、发芽和基膜形成。特定目的2包括实验，旨在验证Alk1是由切应力诱导并在血管重塑中发挥作用的假设。我们将研究血流对斑马鱼胚胎脑血管重构和Alk1表达的影响，以及剪切力对培养的哺乳动物细胞Alk1表达的影响。进一步的实验将确定将机械剪切力转换为Alk1诱导的途径的分子成分。具体目标3包括旨在识别Alk1信号的下游成分的实验。我们将比较VBG突变体和野生型同胞在哺乳动物细胞培养中受活性Alk1调节的基因的表达水平，并通过比较VBG突变体和野生型同胞的内皮转录组来寻找新的Alk1调节基因。综上所述，拟议的实验将确定Alk1是否在血管生成激活、分解和/或重塑中发挥作用，并通过定义下游靶点，将促进对正常血管发育和HHT2发病机制的分子途径的更好理解。