Morphogenesis of the fetal intestinal epithelium

胎儿肠上皮的形态发生

基本信息

批准号：
9177514
负责人：
DEBORAH L. GUMUCIO
金额：
$ 39.77万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-09-21 至 2020-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9177514
关键词：
Adherent Culture Adult Anterior Apical Apoptosis Area Automobile Driving Basement membrane Biological Models Birth CASP3 gene CDX2 gene Cell Cycle Cell Nucleus Cell Survival Cell division Cells Cellular biology Cessation of life Data Daughter Defect Development Developmental Biology Diagnosis Dorsal Endoderm Engineering Ensure Epithelial Epithelial Cells Epithelium Erinaceidae Event Exhibits FLNA gene Failure Figs - dietary Filopodia Fingers Foundations Generations Genetic Goals Golgi Apparatus Growth Human Immigration In Vitro Inherited Intestines Label Life Mechanics Mesenchymal Mesoderm Mitosis Mitotic Modeling Molecular Morphogenesis Mus Mutation Nuclear Organ Organoids Pathway interactions Pattern Period Analysis Play Positioning Attribute Process Property Pseudostratified Epithelium Radial Randomized Resolution Role Shapes Short Bowel Syndrome Site Staging Staining method Stains Surface System Techniques Testing Time Tissues Tube Villus Work absorption abstracting base cell type daughter cell driving force ezrin fetal filamin foot human embryonic stem cell improved in vitro Model intercalation intestinal epithelium intestinal villi mathematical model migration monolayer nutrient absorption pressure square foot stem tool transcriptome

项目摘要

Abstract The adult human intestine is over 20 feet long and has a functional absorptive surface area of nearly 2,000 square feet. Three major processes (which take place prior to birth) establish the effective absorptive surface required to sustain life: a) intestinal lengthening; b) generation of villi and c) apical surface polarization. The molecular processes underlying these attributes are important clinically and therapeutically, but are poorly understood. Work in the last project period established a model of intestinal growth, characterized by rapid proliferation, low apoptosis and directional dispersion of cells along the anterior/posterior (A/P) axis. Analysis of Wnt5a null intestines (a short bowel model) revealed defects in extension of radial filopodia during interkinetic nuclear migration, increased apoptosis, reduced pJNK activity, altered Golgi positioning and reduced Filamin A. Aim 1 is driven by the hypothesis that a Wnt5a-Ror2-Filamin A pathway controls radial filopodial extension, insuring cell survival in the epithelium; this is important for proper lengthening. This pathway will be explored using genetic tools and intestinal explant cultures. At E14.5, subepithelial mesenchymal clusters form, causing overlying epithelial cells to change shape. Epithelial cells between clusters activate Cd44v6; rounded mitotic cells in these regions appear to drive a process of rapid invagination that determines the villus domains. The hypothesis driving Aim 2 is that Epithelial invagination defines the apical surfaces of the first villi; this process is driven by patterned mesenchymal clusters and aided by mechanical forces and specialized cell divisions. The role of intra-epithelial pressure and the need for mitotic progression and oriented cell division will be examined; the basis for impeded invagination in Ezrin-/- mice will be investigated. Finally, the cellular and molecular aspects of apical surface polarization and maturation will be studied in the early human endoderm using a new in vitro model system. The hypothesis underlying Aim 3 is: Human congenital short bowel caused by mutations in FLNA and CLMP result in improper apical polarization. The molecular sequence of polarization will be established in cultures of differentiating CDX2 cells and effects of short bowel mutations on that sequence will be determined. By focusing on the cell biology underlying the developmental biology of the early intestine, these studies are unveiling key processes that establish the template for generation of the apical absorptive surface. Mathematical modeling of the data is revealing which parameters are most critical over developmental time.

抽象的成人肠道长度超过 20 英尺，功能吸收表面积接近 2,000 平方英尺。三个主要过程（发生在出生前）建立有效的吸收表面维持生命所需：a) 肠道延长； b) 绒毛的产生和 c) 顶端表面极化。这这些属性背后的分子过程在临床和治疗上很重要，但很差明白了。上一个项目期间的工作建立了肠道生长模型，其特点是快速增殖、低凋亡和细胞沿前/后（A/P）轴定向分散。分析 Wnt5a 空肠（短肠模型）显示动间运动期间径向丝状伪足的延伸缺陷核迁移、细胞凋亡增加、pJNK 活性降低、高尔基体定位改变和细丝蛋白减少 A. 目标 1 的假设是 Wnt5a-Ror2-Filamin A 通路控制径向丝状足延伸，确保上皮细胞的存活；这对于适当延长很重要。这条路将被探索使用遗传工具和肠道外植体培养。在 E14.5，上皮下间质簇形成，导致上皮细胞改变形状。簇间的上皮细胞激活Cd44v6；这些区域中的圆形有丝分裂细胞似乎驱动着决定绒毛域的快速内陷过程。驱动目标 2 的假设是上皮细胞内陷定义了第一绒毛的顶端表面；这个过程是由图案化的间充质驱动的簇并在机械力和专门的细胞分裂的帮助下。上皮内压和上皮内压的作用将检查有丝分裂进展和定向细胞分裂的必要性；内陷受阻的基础将在 Ezrin-/- 小鼠中进行研究。最后，顶端表面极化和成熟的细胞和分子方面将在使用新的体外模型系统的早期人类内胚层。目标 3 的假设是：人类由 FLNA 和 CLMP 突变引起的先天性短肠导致心尖极化不当。这将在分化 CDX2 细胞的培养物中建立极化的分子序列以及该序列上的短肠突变将被确定。通过关注早期肠道发育生物学基础的细胞生物学，这些研究揭示了建立顶端吸收表面生成模板的关键过程。数据的数学模型揭示了哪些参数在发育过程中最关键。