Stochastic Events Regulating a Notch-Mediated Cell Fate Decision in Caenorhabditis elegans

随机事件调节秀丽隐杆线虫介导的细胞命运决定

• 批准号: 8907446
• 负责人: Michelle Andrea Attner
• 金额: $ 5.42万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2017-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8907446
• 关键词: Address; Adopted; Adult; Affect; Alleles; Animals; Bacteria; Biological; Birth Order; C. elegans genome; Caenorhabditis elegans; Cancer Etiology; Cell Cycle Progression; Cell Cycle Stage; Cells; Decision Making; Defect; Development; Developmental Biology; Developmental Process; Drosophila genus; Embryo; Event; Family member; Feedback; Fertility; Fluorescent in Situ Hybridization; Generations; Genes; Genetic; Genetic Screening; Genetic Transcription; Genome engineering; Goals; Gonadal structure; Human; Image; Lateral; Ligands; Lobular Neoplasia; Malignant Neoplasms; Measures; Mediating; Methods; Microfluidics; Molecular Genetics; Motor Neurons; Nature; Notch Signaling Pathway; Oncogenes; Process; Quantitative Microscopy; RNA Interference; Regulation; Reporter; Research; Retinal; Signal Transduction; Sister; Spinal Cord; Technology; Testing; Time; To specify; Tumor Suppressor Proteins; cell fate specification; cell type; egg; fascinate; granulysin; human disease; improved; in vivo; mRNA Expression; notch protein; novel; novel therapeutic intervention; precursor cell; protein expression; public health relevance; receptor; single molecule; tool; tumor progression; tumorigenesis; Address; Adopted; Adult; Affect; Alleles; Animals; Bacteria; Biological; Birth Order; C. elegans genome; Caenorhabditis elegans; Cancer Etiology; Cell Cycle Progression; Cell Cycle Stage; Cells; Decision Making; Defect; Development; Developmental Biology; Developmental Process; Drosophila genus; Embryo; Event; Family member; Feedback; Fertility; Fluorescent in Situ Hybridization; Generations; Genes; Genetic; Genetic Screening; Genetic Transcription; Genome engineering; Goals; Gonadal structure; Human; Image; Lateral; Ligands; Lobular Neoplasia; Malignant Neoplasms; Measures; Mediating; Methods; Microfluidics; Molecular Genetics; Motor Neurons; Nature; Notch Signaling Pathway; Oncogenes; Process; Quantitative Microscopy; RNA Interference; Regulation; Reporter; Research; Retinal; Signal Transduction; Sister; Spinal Cord; Technology; Testing; Time; To specify; Tumor Suppressor Proteins; cell fate specification; cell type; egg; fascinate; granulysin; human disease; improved; in vivo; mRNA Expression; notch protein; novel; novel therapeutic intervention; precursor cell; protein expression; public health relevance; receptor; single molecule; tool; tumor progression; tumorigenesis

 DESCRIPTION (provided by applicant): This proposal is concerned with how stochastic, initial differences arise in the activity of Notch, which must be properly regulated in development and which, when aberrantly regulated, causes cancer. Stochastic events are utilized from bacteria to humans to mediate myriad developmental processes including cell-fate switching and the generation of cell type diversity. Understanding how stochastic events influence cell fate specification is important to understand how reproducible cell fates are generated from groups of equivalent cells during development. The paradigmatic anchor cell (AC)/ventral uterine (VU) cell fate decision in Caenorhabditis elegans incorporates a stochastic mechanism as part of the process by which initially equivalent cells acquire different fates. The two cells undergoing the AC/VU decision each have the potential to become either an AC or a VU. They interact with each other, mediated by LIN-12/Notch, such that only one becomes the AC and one becomes the VU. During the course of the decision, a stochastic event causes these cells, which initially express both the transmembrane receptor LIN-12/Notch and the transmembrane ligand LAG-2 (a Delta/Serrate/LAG-2 family member), to engage feedback mechanisms that restrict transcription of lin-12 to the presumptive VU and lag-2 to the presumptive AC. The goal of this research is to understand how small, early differences in Notch activity are generated between initially equivalent cells. Birth-order of the AC and VU precursors, a random event, is highly correlated with the subsequent cell fate, suggesting that there is a relationship between cell-cycle progression, Notch signaling, and cell fate specification in the AC/VU decision. Here, we will study this relationship to probe the nature of the stochastic cellular events leading to the specification of the AC and VU by combining the powerful genetics of C. elegans with recent advances in C. elegans genome engineering and in vivo fluorescent imaging. First, we will test whether birth-order of the AC and VU precursors creates or reflects a difference between them by genetically manipulating birth-order and lin-12/Notch level. Second, we will quantify lin-12/Notch expression and activation during the AC/VU decision. We will quantify endogenous lin-12/Notch mRNA and protein expression and develop a novel reporter for lin-12/Notch activity. Third, we will conduct genetic screens to identify novel regulators that control Notch activation i the AC/VU decision and their sister cells by directly imaging the somatic gonad at high magnification. In addition to addressing a central question in developmental biology, studies of Notch-mediated cell fate decisions are highly relevant to cancer: Notch can be an oncogene or tumor suppressor depending on cell context, and studies of how Notch activity is regulated in this cell fate paradigm in C. elegans have identified genes involved in tumorigenesis. Furthermore, illuminating the potential intersection between Notch activity, cell cycle progression, and cell fate specification may suggest novel therapeutic approaches.

 描述（由适用提供）：该提案与Notch活性的随机，初始差异有关，该活动在发育中必须适当调节，并且在受异常调节时会导致癌症。从细菌到人类，随机事件用于介导无数的发育过程，包括细胞命运切换和细胞类型多样性的产生。了解随机事件如何影响细胞脂肪规范对于了解如何从等效细胞组中产生可再现的细胞命运是重要的。秀丽隐杆线虫中的范式锚固细胞（AC）/腹侧子宫（VU）细胞命运决策将随机机制融合为最初等效细胞获得不同命运的过程的一部分。进行AC/VU决定的两个细胞每个都有可能成为AC或VU。它们相互交互，由Lin-12/Notch介导，因此只有一个变成AC，并且一个变成VU。在决定过程中，随机事件导致这些细胞，这些细胞最初同时表达跨膜接收器Lin-12/Notch和Transmmbrane配体Lag-2（Delta/Serrate/Lag-2家族成员），从而使反馈机制限制了将Lin-12转录到Presumive Vu和Lag-2至Prag-2。这项研究的目的是了解最初等效的细胞之间如何产生缺口活性的较小的早期差异。 AC和VU前体的出生序列是一个随机事件，与随后的细胞命运高度相关，这表明在AC/VU决策中，细胞周期进展，Notch信号传导和细胞命运规范之间存在关系。在这里，我们将研究这种关系，以探究随机细胞事件的性质，从而通过将秀丽隐杆线虫的强大遗传学与秀丽隐杆线虫基因组工程和体内荧光成像中的最新进展相结合，从而导致AC和VU的规格。首先，我们将测试AC和VU前体的生育顺序是否通过遗传操纵生育顺序和LIN-12/Notch水平来创造或反映它们之间的差异。其次，我们将在AC/VU决策过程中量化LIN-12/Notch表达和激活。我们将量化内源性LIN-12/NOTCH mRNA和蛋白质表达，并为LIN-12/Notch活性开发新的报告基因。第三，我们将进行遗传筛选，以确定通过直接在高放大倍率上想象体细胞性腺来控制Notch激活I及其姊妹细胞的新型调节剂。除了解决发育生物学中的主要问题外，对Notch介导的细胞脂肪决策的研究与癌症高度相关：NOTCH可以根据细胞环境而成为一种癌基因或肿瘤抑制剂，以及对这种细胞命运中的Notch活性在C. exelelans中如何调节notch活性的研究。此外，阐明Notch活性，细胞周期进程和细胞命运规范之间的潜在相交可能表明新型治疗方法。