MAP kinase regulation of cell-fate transitions in yeast

MAP 激酶对酵母细胞命运转变的调节

• 批准号: 7995234
• 负责人: BEVERLY ERREDE
• 金额: $ 30.07万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-01-01 至 2012-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7995234
• 关键词: Affect; Attenuated; Binding; Bioinformatics; Biological; Cell Fate Control; Cell physiology; Cells; Commit; Computer Simulation; DNA; Data; Data Set; Development; Disease; Dose; Feedback; Gene Expression; Genes; Genetic; Genetic Models; Genetic Programming; Genetic Transcription; Global Change; Growth; Health; Hepatocyte; Homeostasis; Hormones; Human; Image; Individual; Inflammatory; Label; Lead; Learning; Life; Location; Malignant Neoplasms; Maps; Measurement; Mediating; Messenger RNA; Metabolic Diseases; Methodology; Microarray Analysis; Microfluidic Microchips; Mitogen-Activated Protein Kinases; Modeling; Molecular; Molecular Profiling; Monitor; Mutation; Non-Insulin-Dependent Diabetes Mellitus; Organism; Outcome; Partner in relationship; Pathogenesis; Pathway interactions; Pattern; Pheromone; Physiological; Plant Roots; Proteins; Proteomics; RNA; Regulation; Regulatory Pathway; Relative (related person); Resistance; Role; Saccharomyces cerevisiae; Saccharomycetales; Signal Pathway; Signal Transduction; Specific qualifier value; Stimulus; System; Testing; Time; To specify; Transcription Repressor/Corepressor; Translating; Validation; Variant; Yeasts; base; bone cell; brain cell; cell type; cellular development; dosage; genetic manipulation; genome-wide; insight; interdisciplinary approach; mathematical model; model development; mutant; programs; promoter; response; time interval; transcription factor

DESCRIPTION (provided by applicant): Mechanisms that coordinate transcriptional programs in response to specific stimuli are central to understanding normal development and homeostasis. The pheromone-induced transition of budding yeast to either a chemotrophic or mating competent form is a model for dissecting the molecular basis of this regulation. A single mitogen activated protein kinase (MAPK) cascade mediates both transitions. This pathway utilizes two MAPKs, Fus3 and Kss1, that both negatively and positively regulate activity of the Ste12 and Tec1 transcriptional regulators. Ste12 is essential for the changes in gene expression that underlie establishment of both fates while Tec1 is important only for the chemotrophic fate. The genetic program for the chemotrophic fate transition induced by low pheromone concentration is still undefined. Fus3 and Kss1 activation profiles are differentially affected at high vs. low pheromone. We hypothesize that the dose-dependent differences in their activation and their antagonistic regulatory roles control Ste12 and Tec1 activity and degradation in a manner that prepares cells for one or the other differentiation program. We propose a multidisciplinary approach to compare the regulatory networks for the two fates and the molecular basis of the developmental switch: Aim 1. Define the global expression program for chemotrophic growth using microarray technology and compare it to that for mating differentiation. Bioinformatic approaches are proposed to delineate the physiological and phenotypic signatures and regulatory networks that distinguish the two programs. Aim 2. a and b) Combine experimental analyses with computational modeling to quantify the relative contributions from positive and negative regulation by Fus3 and Kss1 and the temporal control of transcription factor degradation on mediating the switch between alternative programs. Empirical measurements of transcription factor abundance and representative mRNAs in wild-type and mutant backgrounds that perturb regulation will be used to test the underlying hypotheses of the model. c) Time-lapse imaging under different pheromone induction regimes will be used to test whether a pheromone gradient reinforces feedback loops that regulate fluctuations and thereby reduce variability in pathway activity and fate determination. Our understanding of the pheromone induced MAPK pathway and the ease of genetic manipulations available with yeast allow discernment of how differences in the amplitude and timing of MAPK activation translate into different transcriptional patterns. Because of the conservation of MAPK pathways, the regulatory paradigms defined here will apply to different MAPK mediated signaling pathways in humans that are at the root of the pathogenesis of hormone dependent cancers, inflammatory diseases, and metabolic disorders. PUBLIC HEALTH RELEVANCE Mitogen activated protein kinase (MAPK) pathways control normal cellular development and function. Differences in the amplitude and timing of MAPK activation are known to affect whether cells divide and multiply or develop into a specialized cell types, such as liver, bone, or brain cells. This proposal exploits advantages of studies with the model genetic organism, S. cerevisiae, to define the molecular mechanisms that translate different patterns of MAPK activation into different developmental fates. The findings will give us a better understanding of how aberrant regulation of these pathways in humans leads to hormone dependent cancers, inflammatory diseases, and metabolic disorders such as Type II diabetes.

描述（由申请人提供）：响应特定刺激的转录程序的机制对于理解正常发育和稳态是至关重要的。信息素诱导的酵母向化学营养或交配的形式转变为剖析该调节的分子基础的模型。单裂原激活的蛋白激酶（MAPK）级联反应两个过渡。该途径利用了两个MAPK，即FUS3和KSS1，它们对Ste12和Tec1转录调节剂的活性进行了负面调节。 Ste12对于基因表达的变化至关重要，基因表达的变化是建立这两种命运的基础，而TEC1仅对化学营养命运很重要。低信息素浓度诱导的化学营养命运转变的遗传程序仍然不确定。在高和低信息素中，FUS3和KSS1激活曲线受到差异影响。我们假设其激活剂量依赖性差异及其拮抗调节作用控制Ste12和Tec1活性和降解，以准备一个或其他分化程序的细胞。我们提出了一种多学科方法，以比较两种命运的监管网络和发育开关的分子基础：目标1。使用微阵列技术定义了全球化学营养增长计划的全球表达程序，并将其与配对分化进行比较。提出了生物信息学方法来描述区分这两个程序的生理和表型特征和调节网络。目标2。a和b）将实验分析与计算模型相结合，以量化FUS3和KSS1的正和负调控的相对贡献以及转录因子降解的时间控制，以介导替代程序之间的转换。在野生型和突变背景中的转录因子丰度和代表性mRNA的经验测量将使用扰动调节来测试模型的基本假设。 c）在不同的信息素诱导状态下进行的延时成像将用于测试信息素梯度是否增强了调节波动的反馈回路，从而降低了途径活动和命运确定的变化。我们对信息素诱导的MAPK途径的理解以及酵母可用的遗传操作的易用性，可以辨别MAPK激活幅度和时机的差异如何转化为不同的转录模式。由于MAPK途径的保存，此处定义的调节范例将适用于人类中不同的MAPK介导的信号通路，这是激素依赖性癌症，炎症性疾病和代谢疾病的发病机理的根源。公共卫生相关性有丝分裂原活化蛋白激酶（MAPK）途径控制正常的细胞发育和功能。已知MAPK激活的幅度和时机的差异会影响细胞分裂并繁殖或发展为专用细胞类型，例如肝脏，骨骼或脑细胞。该建议利用了模型遗传生物葡萄球菌的研究优势，以定义将MAPK激活不同模式转化为不同发育命运的分子机制。这些发现将使我们更好地了解人类对这些途径的异常调节如何导致依赖激素的癌症，炎症性疾病和代谢性疾病，例如II型糖尿病。