Uncovering the role of LRH-1 in enteroendocrine cell development and ‘gut-brain’ communication

项目总结/摘要 背景资料： 肠上皮是人体最大的暴露表面积之一， 与消化、感染监测和代谢相关的多种功能。帮助协调这些 活动是肠内分泌细胞（EECs），表达细胞机制的特化肠上皮细胞 用于化学和机械传感以及通过“肠脑轴”进行宿主通信。肝脏受体 同源物-1（LRH-1，NR 5A 2）是在肠上皮中表达的核受体。我们展示了LRH- LRH-1对这些独特细胞的产生至关重要，LRH-1的缺失导致了显著的内脏损害。 低敏感性在本申请中，我们建议阐明LRH-1促进细胞凋亡的机制， EECs的分化及其丧失对肠-脑通讯的功能后果。 方法： 我们将使用遗传小鼠模型和肠道类器官技术的组合来研究LRH-1， 依赖EEC分化。使用单细胞测序方法，我们将鉴定EEC祖细胞， LRH-1丢失后的人口变化。利用EEC祖细胞荧光标记，我们将观察到， 真实的实时观察LRH-1基因敲除对EEC细胞分化的影响，并描述LRH-1 DNA结合 目标的我们的分子研究将通过评估LRH的功能后果来补充， 1-依赖EEC损失。最后，在我们的急性LRH-1敲除模型中使用详细的解剖学研究将有助于 使我们能够探索快速EEC中断对粘膜神经纤维的影响，粘膜神经纤维是肠道的关键组成部分， 脑轴 目标： 该提案旨在扩展我在K 08调查期间发现的关键发现，并充分 建立我的独立研究项目这些实验将为提交 一个成功的R 01建议建立在肠上皮生理学，核， 受体生物学和神经元信号传导。

Project Summary/Abstract Background: The intestinal epithelium represents one of the largest exposed surface areas of the body and must perform multiple functions related to digestion, infectious surveillance, and metabolism. Helping to coordinate these activities are enteroendocrine cells (EECs), specialized intestinal epithelial cells expressing cellular machinery for chemical and mechanical sensing and for host communication via the ‘Gut-Brain Axis.’ Liver receptor homolog-1 (LRH-1, NR5A2) is a nuclear receptor expressed in the intestinal epithelium. We have shown LRH- 1 is critical for the production of these unique cells and that loss of LRH-1 leads to a remarkable visceral hyposensitivity. In this application, we propose to elucidate both the mechanism(s) by which LRH-1 promotes the differentiation of EECs and the functional consequences of their loss on gut-brain communication. Approach: We will use a combination of genetic mouse models and intestinal organoid technology to investigate LRH-1- dependent EEC differentiation. Using a single cell sequencing approach, we will identify EEC progenitor population shifts following loss of LRH-1. Leveraging an EEC progenitor fluorescent marker, we will observe in real time the effects of LRH-1 knockout on EEC cell differentiation and to delineate the LRH-1 DNA binding targets. Our molecular studies will be complemented by an evaluation of the functional consequences of LRH- 1-dependent EEC loss. Finally, use of detailed anatomic studies in our acute LRH-1 knockout models will enable us to explore the effects of rapid EEC disruption on mucosal nerve fibers, a key component of the gut- brain axis. Goals: This proposal is designed to expand upon a key finding uncovered during my K08 investigation and to fully establish my independent research program. These experiments will provide important data for submission of a successful R01 proposal built at the extraordinary confluence of intestinal epithelial physiology, nuclear receptor biology, and neuronal signaling.