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

项目概要/摘要 背景： 肠上皮是身体最大的暴露表面积之一，必须执行 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（EEC），表达细胞机制的特殊肠上皮细胞 用于化学和机械传感以及通过“肠-脑轴”进行宿主通信。肝受体 同源物-1 (LRH-1, NR5A2) 是一种在肠上皮细胞中表达的核受体。我们已经展示了 LRH- LRH-1 对于这些独特细胞的产生至关重要，LRH-1 的缺失会导致显着的内脏功能障碍。 敏感性低下。在此应用中，我们建议阐明 LRH-1 促进的机制 EEC 的分化及其丧失对肠脑通讯的功能影响。 方法： 我们将结合遗传小鼠模型和肠道类器官技术来研究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 丧失后人口发生变化。利用 EEC 祖细胞荧光标记，我们将观察 实时观察 LRH-1 敲除对 EEC 细胞分化的影响并描绘 LRH-1 DNA 结合 目标。我们的分子研究将通过对 LRH- 功能后果的评估来补充。 1 相关 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 使我们能够探索快速 EEC 破坏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 K08 调查期间发现的一项重要发现，并充分 建立我的独立研究计划。这些实验将为提交提供重要数据 一个成功的 R01 提案建立在肠上皮生理学、核学的非凡融合之上 受体生物学和神经信号传导。

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.