Epidermal polarization: the desmosomal cadherin desmoglein 1 regulates tissue mechanics and barrier function

表皮极化：桥粒钙粘蛋白桥粒糖蛋白 1 调节组织力学和屏障功能

基本信息

批准号：
9904494
负责人：
Joshua Allen Broussard
金额：
$ 8.79万
依托单位：
NORTHWESTERN UNIVERSITY AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-04-03 至 2022-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9904494
关键词：
3-Dimensional Ablation Actins Actomyosin Adhesives Affect Apical Architecture Area Atomic Force Microscopy Atopic Dermatitis Autoimmune Process Bacterial Toxins Basal Cell Biochemical Biological Assay Body Fluids Cadherins Cell Proliferation Cell Shape Cell physiology Cells Cellular Morphology Chemicals Cytoskeleton Data Defect Desmosomes Development Disease EMS1 gene ERBB2 gene Epidermal Growth Factor Receptor Epidermis Epithelial Epithelium ErbB Receptor Family Protein Etiology Exhibits Family Fluorescence Future Growth Health Heart Hereditary Disease Human Intermediate Filaments Ions Lasers Link Measures Mechanical Stress Mechanics Mediating Membrane Membrane Proteins Molecular Movement Normal tissue morphology Organelles Patients Pattern Play Population Prevalence Process Property Proteins Psoriasis Receptor Protein-Tyrosine Kinases Regulation Role Shapes Signal Transduction Signaling Molecule Simple Epithelium Skin Spectrum Analysis Stratification Stratified Epithelium Stratum Basale Stratum Granulosum Structure Surface System Testing Tight Junctions Time Tissues Work apical membrane basolateral membrane desmoglein 1 human model insight intestinal epithelium loss of function mechanical properties member molecular marker mouse model polymerization prevent protein complex protein expression receptor self-renewal skin barrier skin disorder src-Family Kinases stem cells wound healing

项目摘要

Cells within all types of epithelia are polarized such that they have distinct domains at their lower and upper regions. For example, in simple epithelia, which consist of a single layer of cells, there are specialized protein complexes near their apical surface that are essential for holding cells together, limiting the passage of molecules and ions through the space between cells, and stopping the movement of membrane proteins between the apical and basolateral membranes. These structures coordinate with cytoskeletal networks to generate contractile forces that are essential in regulating tissue growth, shape, movement, and barrier establishment. Multilayer epithelial tissues, like the epidermis of the skin, are also polarized, but across many cell layers. How these patterns emerge in the epidermis and how they regulate normal tissue functions are not fully understood. This study will focus on the cadherin desmoglein 1 (Dsg1), which is a part of the desmosome, a cell-cell adhesive organelle. Dsg1 is a disease target involved in autoimmune, bacterial toxin-mediated, and inherited diseases and is only expressed in multilayer epithelia. The amount of Dsg1 present in each of the layers of the skin is patterned, with very little protein in the lowest layer and increasing amounts toward the outer layers. This suggests that the functional overlay of patterned Dsg1 onto the baseline machinery found in simple epithelia led to new mechanisms to increase tissue complexity. Preliminary studies indicate that there is a region under high tension in the outermost living layers of the epidermis. Moreover, loss of Dsg1 resulted in a shift in the localization of this high-tension region. It is known that skin is under tension, and that tension contributes to the growth of epidermal tissue as well as to the process of wound healing. In Aim 1 of this proposal, we will use laser ablation and atomic force microscopy to test the role of Dsg1 in regulating epidermal tissue mechanics (tension and stiffness). I hypothesize this occurs through Dsg1 integrating with modulators of the actin cytoskeleton, known regulators of cell forces. Chemical signaling platforms are also patterned in the epidermis, including members of the epidermal growth factor receptor (ErbB) family. The best-known member, epidermal growth factor receptor (EGFR), plays an important role in regulating cell proliferation in the basal layer of the epidermis. However, the functions of other members in the skin are not well known. Preliminary data show that ErbB2 is located in the uppermost living layers of the epidermis, where tight junctions are formed. Tight junctions are an integral part of the epidermal barrier, preventing loss of body fluids and entrance of foreign substances. Dsg1 regulates the total amount and the activity of ErbB2, and together Dsg1 and ErbB2 regulate tight junction proteins. Aim 2 of this proposal will ascertain the mechanism by which Dsg1 affects ErbB2, and the extent to which these proteins work together to regulate the formation and function of the epidermal barrier. Future work will examine the effects of Dsg1-mediated mechanics on ErbB2 activity and barrier function, linking Aims 1 and 2. I propose that Dsg1 integrates mechanical and chemical signals to control the polarized architecture and function of the epidermis.

所有类型的上皮细胞内的细胞都是极化的，因此它们的下层和上层具有不同的域地区。例如，在由单层细胞组成的简单上皮细胞中，有专门的蛋白质靠近顶端表面的复合物对于将细胞固定在一起、限制分子的通过至关重要和离子通过细胞之间的空间，并阻止膜蛋白在顶端之间的运动和基底外侧膜。这些结构与细胞骨架网络协调产生收缩性对于调节组织生长、形状、运动和屏障建立至关重要的力。多层上皮组织，如皮肤的表皮，也是极化的，但跨越许多细胞层。这些如何表皮中出现的模式以及它们如何调节正常组织功能尚不完全清楚。这研究将重点关注钙粘蛋白桥粒糖蛋白 1 (Dsg1)，它是桥粒的一部分，桥粒是一种细胞与细胞的粘合剂细胞器。 Dsg1 是涉及自身免疫性疾病、细菌毒素介导的疾病和遗传性疾病的疾病靶点并且仅在多层上皮细胞中表达。皮肤各层中 Dsg1 的含量为图案化，最底层蛋白质含量极少，越往外层蛋白质含量越多。这表明图案化的 Dsg1 与简单上皮细胞中发现的基线机制的功能重叠导致增加组织复杂性的新机制。初步研究表明，存在一个区域处于高表皮最外层活层的张力。此外，Dsg1 的丢失导致定位的转变这个高压地区。众所周知，皮肤处于紧张状态，而这种紧张会促进皮肤的生长。表皮组织以及伤口愈合过程。在本提案的目标 1 中，我们将使用激光烧蚀和原子力显微镜测试Dsg1在调节表皮组织力学（张力和张力）中的作用刚性）。我假设这是通过 Dsg1 与肌动蛋白细胞骨架调节剂整合而发生的，已知细胞力的调节者。化学信号平台也在表皮中形成图案，包括表皮生长因子受体 (ErbB) 家族。最知名的成员，表皮生长因子受体 (EGFR)，在调节表皮基底层细胞增殖中发挥重要作用。然而，皮肤中其他成员的功能尚不清楚。初步数据显示，ErbB2 位于表皮最上面的活层，在那里形成紧密的连接。紧密连接是不可分割的一部分表皮屏障，防止体液流失和异物进入。 DSg1 调节总量 ErbB2 的量和活性，以及 Dsg1 和 ErbB2 一起调节紧密连接蛋白。这个目标2 该提案将确定 Dsg1 影响 ErbB2 的机制，以及这些蛋白质发挥作用的程度共同调节表皮屏障的形成和功能。未来的工作将检查其影响 Dsg1 介导的 ErbB2 活性和屏障功能机制，连接目标 1 和 2。我建议 Dsg1 整合机械和化学信号来控制表皮的极化结构和功能。