Stochastic vs. Deterministic Cell Fate Choice in Fly Retinal Patterning

果蝇视网膜图案中的随机与确定性细胞命运选择

• 批准号: 8718730
• 负责人: Michael William Perry
• 金额: $ 2.29万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2014-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8718730
• 关键词: Adult; Animals; Antibodies; Biochemical; Biological Models; Cell Fate Control; Cell Nucleus; Cells; Choices and Control; Chromatin; Collecting Cell; Color; Complex; Data; Data Set; Development; Drosophila genus; Embryo; Enhancers; Eye; Gene Expression; Gene Expression Profile; Genes; Genetic; Genome; Genomics; Goals; Hereditary Disease; Homologous Gene; Human; In Situ; In Situ Hybridization; Lead; Malignant Neoplasms; Methods; Noise; Nucleic Acid Regulatory Sequences; Organ; Outcome; Pathway interactions; Pattern; Pharmaceutical Preparations; Photoreceptors; Plasmids; Play; Polyribosomes; Population; Production; Protocols documentation; Regulation; Reporter; Research; Research Design; Retina; Retinal; Role; Sampling; Signal Transduction; Signaling Molecule; Sodium Chloride; Sorting - Cell Movement; Specific qualifier value; System; Techniques; Testing; Therapeutic Agents; Transgenic Organisms; Visual system structure; base; cell fate specification; cell type; comparative; fly; gene function; genome sequencing; genome-wide; insight; interest; mRNA Expression; mutant; programs; public health relevance; relating to nervous system; sensory system; tool; transcription factor

DESCRIPTION (provided by applicant): Cell fate can be specified during development in two fundamentally different ways. In most cases, fate decisions depend on specific signals that produce essentially hardwired, highly reproducible outcomes. In a number of important alternate cases, differentiated cell types arise instead by chance, through stochastic mechanisms. One of the best studied examples of this second strategy is the specification of photoreceptor subtypes in the Drosophila retina. We have identified a related group of flies that instead make the same neural fate decision in a deterministic and highly ordered way, producing alternating single rows of photoreceptor subtypes instead of the random salt and pepper distribution in the Drosophila retina. Objectives: Our preliminary studies indicate that differential regulation of the key transcription factor Spineless is critical in both systems. We propose a comparative approach to characterize upstream and downstream components in the "ordered" system and to further dissect the context and regulatory control of this decision in both systems. Specific Aims: (1) To characterize retinal patterning in the alternate, ordered system (Dolichopodidae, or "Doli") and to test its function; (2) to better understand each how each cell fate determination system is controlled by identifying regulatory regions of critical determinants; and (3) to further dissect photoreceptor subtype specification in Drosophila by applying newly developed genomic tools. Study design: We are sequencing the genome and transcriptome of two species in the "deterministic" system (Doli). This will allow us to characterize mRNA expression patterns of genes in the retinal patterning network, alongside traditional antibody development for key transcription factors. To assess potentially conserved regulatory function we will test candidate regions from Doli in Drosophila as well as develop transgenic techniques in Doli. To further evaluate the role and function of upstream and downstream components of this fate decision in Drosophila, we will use FACS-sorted, cell-type specific populations of photoreceptor nuclei for transcriptional and chromatin mark profiling. Overall relevance: These studies will contribute to our understanding of how different types of cell fate choice are controlled. The discovery of two closely related but alternate systems provides an ideal opportunity to study the role of underlying biochemical "noise" in the expression of critical cell fate determinants and how it might be utilized - or limited. Several important components of this cell fate specification system and its targets have been implicated in cancer directly, including the human homolog of Spineless itself. Ultimately, a better understanding of how cell fate is determined and maintained will lead to new strategies for targeting therapeutic agents and drugs to specific cell fate specification pathways when cell fate is mis-specified or lost, as often occurs in cancer and in the progression of genetic diseases.

描述(由申请人提供)：在发育过程中，细胞命运可以用两种根本不同的方式来指定。在大多数情况下，命运决定取决于特定的信号，这些信号产生基本上固定的、高度可重复性的结果。在一些重要的替代案例中，分化的细胞类型是通过随机机制偶然出现的。第二种策略研究得最好的例子之一是指定果蝇视网膜中的光感受器亚型。我们已经确定了一组相关的果蝇，它们以确定性和高度有序的方式做出相同的神经命运决定，产生交替的单行光感受器亚型，而不是果蝇视网膜中随机分布的盐和胡椒。目的：我们的初步研究表明，对关键转录因子无刺的差异调控在这两个系统中都是至关重要的。我们提出了一种比较的方法来表征“有序”系统中的上游和下游组件，并进一步剖析这两个系统中这一决定的背景和监管控制。具体目标：(1)表征交替有序系统(Doli)中的视网膜模式并测试其功能；(2)通过识别关键决定因素的调控区域，更好地了解每个细胞命运决定系统是如何控制的；以及(3)通过应用新开发的基因组工具，进一步剖析果蝇的光感受器亚型规范。研究设计：我们正在对“确定性”系统(DOLI)中两个物种的基因组和转录组进行测序。这将使我们能够表征视网膜图案网络中基因的mRNA表达模式，以及关键转录因子的传统抗体开发。为了评估潜在的保守调控功能，我们将测试果蝇Doli的候选区域，并开发Doli的转基因技术。为了进一步评估这种命运决定的上游和下游组件在果蝇中的作用和功能，我们将使用FACS分类的、细胞类型特定的光感受器核群体来进行转录和染色质标记分析。总体相关性：这些研究将有助于我们理解不同类型的细胞命运选择是如何被控制的。两个密切相关但相互交替的系统的发现为研究潜在的生化“噪音”在关键细胞命运决定因素的表达中的作用以及如何利用或限制提供了一个理想的机会。这个细胞命运规范系统的几个重要组成部分 而且它的靶点已经直接与癌症有关，包括无骨的人类同系物本身。最终，更好地了解细胞命运是如何确定和维持的，将导致新的策略，当细胞命运被错误指定或丢失时，针对特定细胞命运指定路径的治疗剂和药物将导致新的策略，如在癌症和遗传病的进展中经常发生的那样。