Regulation of pluripotent differentiation by gene circuit interactions.

通过基因电路相互作用调节多能分化。

• 批准号: 8605802
• 负责人: Gurol Mehmet Suel
• 金额: $ 29.41万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-04 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8605802
• 关键词: Regulation; pluripotent; differentiation; gene; circuit

DESCRIPTION (provided by applicant): Cellular processes are controlled by gene regulatory circuits that are comprised of interactions among genes and proteins. One such process common to organisms ranging from bacteria to mammalian stem cells is pluripotent differentiation, where cells can differentiate into one of several possible fates. We propose to investigate how interactions at the molecular level within and across genetic circuits determine pluripotent differentiation at the cellular level. We will study pluripotent differentiation in Bacillus subtilis, a simple, well characterized and experimentally accessible system as a model for genetic control of cell fate choice. Environmental stress induces B. subtilis cells to undergo sporulation or differentiate into the competence state and take up extracellular DNA and incorporate it into their chromosome. We have recently identified the core competence circuit and showed that it exhibits excitable dynamics triggered by noise. Many of the molecular components that regulate competence and sporulation in B. subtilis are known. How interactions within and across competence and sporulation circuits regulate the choice and execution of appropriate differentiation programs is, however, poorly understood. We will study this problem using quantitative fluorescence time- lapse microscopy at the single-cell level to establish how the dynamics of molecular interactions regulate this process. Exploiting genetic manipulation techniques available for B. subtilis, we will measure how systematic re-engineering of circuit interactions control differentiation. Utilizing established connectivity maps of competence and sporulation circuits, we will also construct mathematical frameworks to generate predictions and analyze results. Specifically, we will apply these methods to: (1) Determine the functional importance of competence circuit architecture by comparing it to engineered alternative topologies in silico and in vivo. (2) Determine the functional importance of cross-regulation in cell fate choice. (3) Determine how the transient activity of the competence circuit alters the progression and execution of sporulation. This integrative research is necessary to determine how molecular interactions within and across genetic circuits control pluripotent differentiation at the cellular level. Identification of the mechanics that dictate the choice and execution of cell fate in this model organism are likely to be relevant to pluripotent differentiation in diverse organisms including mammalian systems. PUBLIC HEALTH RELEVANCE: This proposal will establish a comprehensive description of how bacteria undergo differentiation. The resulting data will be relevant to: 1) Controlling differentiation in bacteria to prevent bacterial spore formation in foods. 2) Preventing the ability of bacteria to naturally become resistant to antibiotics. 3) Developing new techniques to control how cells differentiate, which can be applied in the future to control differentiation of mammalian stem cell to substitute for any missing or diseased cell types.

描述（由申请人提供）：细胞过程由基因调控回路控制，基因调控回路由基因和蛋白质之间的相互作用组成。从细菌到哺乳动物干细胞的生物体共同的一个这样的过程是多能分化，其中细胞可以分化成几种可能的命运之一。我们建议调查如何在分子水平上的相互作用，并在遗传电路决定在细胞水平上的多能分化。我们将研究枯草芽孢杆菌的多能分化，枯草芽孢杆菌是一个简单的、特征良好的、实验上可访问的系统，作为细胞命运选择的遗传控制模型。环境胁迫诱导B。枯草杆菌细胞经历孢子形成或分化成感受态，并摄取细胞外DNA并将其并入其染色体中。我们最近确定了核心竞争力电路，并表明它具有由噪声触发的兴奋动力学。在B中调节感受态和孢子形成的许多分子组分。subtilis是已知的。然而，人们对能力和孢子形成回路内部和之间的相互作用如何调节适当分化程序的选择和执行知之甚少。我们将在单细胞水平上使用定量荧光延时显微镜来研究这个问题，以确定分子相互作用的动力学如何调节这个过程。利用可用于B的遗传操作技术。subtilis，我们将测量如何系统地重新设计电路的相互作用控制分化。利用已建立的能力和孢子形成电路的连接图，我们还将构建数学框架来生成预测和分析结果。具体来说，我们将这些方法应用于：（1）通过比较它在硅片和体内的工程替代拓扑结构，确定功能的重要性的能力电路架构。(2)确定交叉调节在细胞命运选择中的功能重要性。(3)确定能力回路的短暂活动如何改变孢子形成的进展和执行。这种综合性研究对于确定遗传电路内和遗传电路之间的分子相互作用如何在细胞水平上控制多能分化是必要的。在该模型生物体中决定细胞命运的选择和执行的机制的鉴定可能与包括哺乳动物系统在内的多种生物体中的多能分化有关。公共卫生相关性：该提案将全面描述细菌如何分化。所得数据将与以下方面相关：1）控制细菌的分化以防止食物中细菌孢子的形成。2)防止细菌自然对抗生素产生耐药性。3)开发控制细胞分化的新技术，未来可用于控制哺乳动物干细胞的分化，以替代任何缺失或患病的细胞类型。