Lrig1-Expressing Colonic Stem Cells in Homeostasis and Repair

表达 Lrig1 的结肠干细胞在稳态和修复中的作用

基本信息

批准号：
9341258
负责人：
Anne E Zemper
金额：
$ 16.8万
依托单位：
UNIVERSITY OF OREGON
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-09-01 至 2018-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9341258
关键词：
Acute Affect Age Biochemical Biological Assay Cell Differentiation process Cell Proliferation Cell physiology Cells Cessation of life Chronic Colon Colorectal Cancer Complement Coupling Data Development Plans Disease Environment Epidermal Growth Factor Receptor Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor Epithelial Epithelium Evolution Extramural Activities Fluorescence Microscopy Funding Genetic Transcription Goals Growth Growth Factor Health Histologic Homeostasis Human Image Immunoglobulin Domain Impaired wound healing Inflammation Injury Internal Ribosome Entry Site Intestines Knockout Mice Knowledge LGR5 gene Leucine-Rich Repeat Ligation Link Literature Maintenance Malignant - descriptor Mediating Mentored Research Scientist Development Award Mentors Mesenchyme Microscopic Microscopy Modeling Molecular Mucous Membrane Mus National Institute of Diabetes and Digestive and Kidney Diseases Natural regeneration Phase Play Population Process Production Property Proteins Recovery Regenerative response Regulation Reporter Repression Research Research Proposals Resolution Role Running Signal Transduction Small Intestines Sodium Dextran Sulfate Stem cells Tamoxifen Testing Tissues Training Transcript Work Wound Healing Wounds and Injuries adult stem cell career development cell growth cohort colonic crypt design human tissue imaging study improved in vivo injury and repair insight migration mouse model progenitor programs public health relevance regenerative repaired response response to injury skills stem stem cell population tissue regeneration tissue repair tool

项目摘要

DESCRIPTION (provided by applicant): This NIDDK Mentored Research Scientist Development Award application describes a three-year training plan designed to allow me to acquire additional skill and knowledge so that I can transition into directing my own independent and productive research program. In carrying out the proposed research, and by following a carefully mentored career development plan in a collegial research environment, I will add to my scientific repertoire by acquiring expertise in intestinal epithelial injury models and as well as live-cell and super-resolution microscopy. Using this newly acquired expertise, I will establish a scientific niche that will set me apart from my mentors and pave the way to a robust, extramurally funded research program. The research proposed in this application will focus on understanding how colonic stem cells function in repair after epithelial injury. It is known that Egfr signaling is activated after injury and this contributes to repair; however, this activation ad subsequent growth and proliferation, must be tightly regulated to avoid aberrant overgrowth. I have found that an Egfr inhibitor, Lrig1, marks a population of largely quiescent colonic stem cells, unlike the well-characterized, proliferative stem cell population marked by Lgr5. My proposal seeks to clarify the role of both Lrig1+ stem cells, and the role of Lrig1 as a negative regulator of Egfr, in colonic tissue stem cell homeostasis and wound healing. The requirement of stem cell populations in repair after injury has not yet been tested; this is critical to our understanding of the colonic epithelial crypt niche requirements for promoting proper regeneration. My Specific Aims are designed to test my over-arching hypothesis that Lrig1 is expressed in regenerative progenitor cells, in response to an active growth factor signal, such as activated Egfr signaling. In Aim 1, I will eliminate both Lrig1- and Lgr5-expressing stem cells before and after wound healing, to test their requirement in injury repair. I will evaluate initial injury and end-stage wound-repair by histological, molecular, and super-resolution analysis. In Aim 2, to examine the influence of Lrig1 on Egfr in wound healing, I will examine the effects of the absence of Lrig1 in wound healing, using Lrig1 null mice, and use advanced microscopy to examine the dynamics of Egfr activation. With the evolution of tools to manipulate stem cell populations in vivo, only now are the studies proposed here possible. Moreover, Vanderbilt's super-resolution microscopic capabilities will enable me to examine colon cell dynamics in tissue repair after injury at a resolution not previously possible. By coupling sophisticated mouse modeling with super-resolution imaging, the studies proposed here directly test the relationship between Lrig1- and Lgr5-expressing stem cells in injury repair, as well as examine the role of Lrig1 as a negative regulator of Egfr activity in this wound-healing context. The goal of this Mentored Research Scientist Development Award is to develop the expertise that will allow me to run an independent, funded research program that will contribute to improving human health and disease.

描述（由申请人提供）：这份 NIDDK 指导研究科学家发展奖申请描述了一项为期三年的培训计划，旨在让我获得额外的技能和知识，以便我能够过渡到指导我自己的独立和富有成效的研究项目。在开展拟议的研究时，并通过在大学研究环境中遵循精心指导的职业发展计划，我将通过获得肠上皮损伤模型以及活细胞和超分辨率显微镜方面的专业知识来丰富我的科学技能。利用这些新获得的专业知识，我将建立一个科学领域，使我有别于我的导师，并为一个强大的、外部资助的研究项目铺平道路。本申请提出的研究将重点了解结肠干细胞在上皮损伤后的修复中如何发挥作用。众所周知，Egfr 信号传导在损伤后被激活，这有助于修复；然而，这种激活以及随后的生长和增殖必须受到严格调节，以避免异常过度生长。我发现 Egfr 抑制剂 Lrig1 标记了一群大部分处于静止状态的结肠干细胞，这与 Lgr5 标记的充分表征的增殖干细胞群不同。我的提案旨在阐明 Lrig1+ 干细胞的作用以及 Lrig1 作为 Egfr 负调节因子在结肠组织干细胞稳态和伤口愈合中的作用。损伤后修复中干细胞群的需求尚未经过测试；这对于我们了解结肠上皮隐窝生态位促进适当再生的要求至关重要。我的具体目标旨在测试我的总体假设，即 Lrig1 在再生祖细胞中表达，响应活跃的生长因子信号，例如激活的 Egfr 信号。在目标 1 中，我将在伤口愈合前后消除表达 Lrig1 和 Lgr5 的干细胞，以测试它们在损伤修复中的需求。我会初步评估通过组织学、分子和超分辨率分析进行损伤和终末期伤口修复。在目标 2 中，为了检查 Lrig1 对伤口愈合中 Egfr 的影响，我将使用 Lrig1 null 小鼠检查 Lrig1 缺失对伤口愈合的影响，并使用先进的显微镜检查 Egfr 激活的动态。随着体内操纵干细胞群的工具的发展，直到现在这里提出的研究才成为可能。此外，范德比尔特的超分辨率显微能力将使我能够以以前不可能的分辨率检查损伤后组织修复中的结肠细胞动态。通过连接精密的鼠标通过超分辨率成像建模，本文提出的研究直接测试了表达 Lrig1 和 Lgr5 的干细胞在损伤修复中的关系，并检查了 Lrig1 在伤口愈合过程中作为 Egfr 活性负调节因子的作用。指导研究科学家发展奖的目标是培养专业知识，使我能够运行一个独立的、受资助的研究项目，为改善人类健康和疾病做出贡献。