Diversity-generating mechanisms for mammalian intercalated cell lineages

哺乳动物闰细胞谱系的多样性生成机制

• 批准号: 10640099
• 负责人: Riana Kin Parvez
• 金额: $ 4.77万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10640099
• 关键词: ATAC-seq; Address; Alleles; American; B-Lymphocytes; Binding; Binding Sites; Biochemical; Biological Assay; Body Fluids; Cell Culture System; Cell Lineage; Cell Nucleus; Cell physiology; Cells; Cellular biology; Characteristics; Chromatin; Complement; Data; Data Correlations; Data Set; Detection; Development; Developmental Process; Dialysis procedure; Disease; Duct (organ) structure; End stage renal failure; Environment; Epithelium; Equilibrium; Exhibits; Family; Filtration; Gene Expression; Generations; Genes; Genetic Models; Genetic Transcription; Homeostasis; Human; Immunohistochemistry; In Vitro; Intercalated Cell; Intermediate Mesoderm; Kidney; Kidney Transplantation; Knowledge; Liquid substance; Methods; Modeling; Molecular; Nephrons; Organoids; Patients; Pattern; Physiological; Play; Population; Process; Production; Regulation; Renal Replacement Therapy; Renal function; Repression; Role; Sodium Chloride; System; Time; Tissues; Transcriptional Regulation; Water; Work; absorption; cell type; chromatin immunoprecipitation; genetic approach; in vivo; insight; interest; kidney cell; loss of function; mouse genetics; mutant; nephron progenitor; pH Homeostasis; postnatal; progenitor; programs; salt balance; single-cell RNA sequencing; stem cells; transcription factor

Project Summary/Abstract Three-quarters of a million Americans have End Stage Renal Disease (ESRD). Their only treatment options are dialysis, with poor long term survival prospects, or a curative kidney transplant, with too few kidneys to meet patient need. One way to address the shortage of transplantable kidneys is to develop a thorough insight into essential cell types and how they are generated, and then to use this insight to generate functional, cell-based kidney replacements. The physiologically relevant epithelial networks of the kidney arise from two distinct progenitor populations. Nephron progenitors generate the nephrons, of which there are approximately one million in the human kidney, and adjacent ureteric progenitors generate the branched network to the collecting system, to which nephrons connect. Homeostasis is maintained by specialized cell types in both the nephron and the collecting duct. Notably, water and salt, and pH balance, are regulated by principal cells (PCs) and intercalated cells (ICs), respectively. There are three subtypes of intercalated cells: type A intercalated cells (A-ICs), type B intercalated cells (B-ICs) and non-A-non-B intercalated cells that perform distinct functions in the regulation of pH homeostasis. Interestingly, the McMahon group recently demonstrated both PCs and ICs have dual origins from both nephron and ureteric progenitor cells, an unusual developmental process. Here, I aim to identify the mechanisms generating similar, but not identical, IC subtypes from distinct kidney progenitor populations. In Specific Aim 1, I will focus on identifying the targets of transcription factors that are known to be essential for the development of ICs: Tfcp2l1 and Foxi1. I will also profile the targets of transcription factors that have not yet been described in ICs: Dmrt2 distinguishes both nephron and ureteric epithelial derived IC-A cell types from Hmx2/Hmx3 expressing IC-B cell types. Differential Hmx gene expression sub-divides the IC-B populations: Hmx2+ B-ICs and non-A-nonB ICs are nephron-derived and Hmx2+/Hmx3+ B-ICs are ureteric lineage derived. We hypothesize that Tfcp2l1 and Foxi1 initiate a general IC developmental program, while Dmrt2, Hmx2, and Hmx3 have mutually repressive actions in the generation of IC subtypes. I will use biochemical approaches and generate tagged alleles to identify regulatory interactions for these transcription factors within ICs of both lineages. In Specific Aim 2, I will use genetic approaches in vivo and a ureteric organoid model to determine the requirement of these factors in the functional transcriptional interplay generating mammalian ICs. Taken together, this proposed work will define a regulatory framework for the development of intercalated cells within the ureteric and nephron lineages in the kidney and provide new insights into the regulatory programs governing cell types involved in mammalian kidney function.

项目概要/摘要 一百万美国人中有四分之三患有终末期肾病 (ESRD)。他们唯一的治疗选择是 长期生存前景不佳的透析，或肾脏太少无法满足需要的治疗性肾移植 患者需要。解决可移植肾脏短缺问题的一种方法是深入了解 基本细胞类型及其生成方式，然后利用这种见解来生成功能性的、基于细胞的细胞 肾脏替代品。肾脏的生理相关上皮网络来自两个不同的 祖先群体。肾单位祖细胞产生肾单位，其中大约有一百万个 在人类肾脏中，相邻的输尿管祖细胞生成通往收集系统的分支网络， 肾单位连接的地方。肾单位和肾单位中的特殊细胞类型维持稳态 集合管。值得注意的是，水和盐以及 pH 平衡是由主细胞 (PC) 和插层细胞调节的。 细胞（IC），分别。闰细胞分为三种亚型：A 型闰细胞 (A-IC)、B 型 嵌入细胞 (B-IC) 和非 A-非 B 嵌入细胞在调节中发挥不同的功能 pH 稳态。有趣的是，麦克马洪小组最近证明了 PC 和 IC 具有双重起源 来自肾单位和输尿管祖细胞，这是一个不寻常的发育过程。在这里，我的目的是确定 从不同的肾祖细胞群中产生相似但不相同的 IC 亚型的机制。在 具体目标 1，我将重点关注确定已知对转录至关重要的转录因子的靶标 开发IC：Tfcp2l1和Foxi1。我还将分析尚未发现的转录因子的靶标 ICs 中已进行了描述：Dmrt2 将肾单位和输尿管上皮衍生的 IC-A 细胞类型与 表达 Hmx2/Hmx3 的 IC-B 细胞类型。差异 Hmx 基因表达对 IC-B 群体进行了细分： Hmx2+ B-IC 和 non-A-nonB IC 源自肾单位，而 Hmx2+/Hmx3+ B-IC 源自输尿管谱系。 我们假设 Tfcp2l1 和 Foxi1 启动了通用 IC 开发程序，而 Dmrt2、Hmx2 和 Hmx3在IC亚型的产生中具有相互抑制作用。我将使用生化方法 生成标记的等位基因，以识别两个 IC 内这些转录因子的调控相互作用 血统。在具体目标 2 中，我将使用体内遗传方法和输尿管类器官模型来确定 这些因素在产生哺乳动物 IC 的功能性转录相互作用中的需要。采取 总之，这项拟议的工作将为插层细胞的发展定义一个监管框架 肾脏中的输尿管和肾单位谱系，并为管理程序提供新的见解 参与哺乳动物肾功能的细胞类型。