Exploring lateral root formation in the context of a 'clock and wavefront' model

在“时钟和波前”模型的背景下探索侧根的形成

• 批准号: 8053272
• 负责人: Jaimie M. Van Norman
• 金额: $ 5.47万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8053272
• 关键词: Accounting; Address; Behavior; Biological; Biomass; Carbon; Cells; Chemicals; Development; Developmental Process; Environment; Eukaryota; Fiber; Food; Genes; Health; Hormones; Human; Image; Lateral; Luciferases; Methods; Modeling; Molecular; Pattern; Periodicity; Plant Roots; Plants; Positioning Attribute; Process; Quantitative Trait Loci; Reporter; Retinoids; Segmentation Clock Pathway; Shelter facility; Signal Transduction; Soil; Somites; Source; Specific qualifier value; Structure; System; Testing; Time; Transgenic Plants; Translating; Travel; Variant; Vertebrates; biological systems; climate change; improved; insight; novel; public health relevance; research study; response; somitogenesis; trait

DESCRIPTION (provided by applicant): Periodic structures are formed during development in diverse biological systems. The main objective of this proposal is to examine the periodic formation of lateral roots (LRs) in plants, within the framework established by the 'clock-and-wavefront' model for the periodic formation of somites in vertebrates. The model for somitogenesis proposes that a traveling molecular oscillator, the segmentation clock, sets the period of somite formation. The clock signal is translated into a spatial pattern of periodic segments by interaction with two opposing signaling gradients at the 'wavefront', which is where cells become competent to form somites in response to the clock signal. This 'clock-and-wavefront' mechanism accounts for the periodic serial formation of somites along the vertebrate axis. A traveling molecular oscillator has also been identified in roots and disruption of it alters LR formation. Moreover, one hormone gradient is already predicted in the root and we have evidence implicating a second gradient. We propose that the 'clock-and-wavefront' mechanism may be a common regulatory strategy in the formation of periodic structures in diverse multicellular eukaryotes. To test our hypothesis that a 'clock-and-wavefront' mechanism is operating in LR development, three specific aims will be addressed. The behavior of the oscillation will be examined and mathematically modeled. The hypothesis that a retinoid gradient operates in the root will be tested and the interaction of the gradient with the oscillation will be examined. Additionally, natural variation in LR formation will be used to identify genes involved in this process. The primary method in analyzing the oscillation and the gradient in LR formation will be real-time imaging of luciferase reporters in transgenic plants. The response of the oscillation and subsequent competency to form a LR will be examined upon manipulation of the gradients by chemical and molecular biological methods. The results of these experiments will be used to mathematically model the behavior of the oscillation and its interaction with the gradient. Finally, natural variation in LR formation will be used to identify genes involved in this process by association studies and analysis of quantitative trait loci. These studies constitute a novel way of analyzing LR development and will reveal insight into the fundamental question of how LR periodicity is established and maintained.

描述（由申请人提供）：在多种生物系统的开发过程中形成了周期结构。该提案的主要目的是在植物中检查植物中侧根（LRS）的周期性形成，这是在“时钟和波前”模型建立的框架中为脊椎动物定期形成的框架。体积发生的模型提出，行进的分子振荡器（分割时钟）设置了体积形成周期。通过与“波前”的两个相对信号梯度相互作用，将时钟信号转换为周期性段的空间模式，这是细胞根据时钟信号响应响应时钟信号形成节点的地方。这种“时钟和波前”机制解释了沿脊椎动物轴的周期性序列形成。在根部和破坏中，也已经确定了行进的分子振荡器改变了LR的形成。此外，已经预测了一种激素梯度，我们有证据表明第二梯度。我们建议“时钟和波前”机制可能是多种细胞真核生物周期性结构形成的常见调节策略。 为了检验我们在LR开发中运行的“时钟和波前”机制的假设，将解决三个具体目标。振荡的行为将进行检查和数学建模。将测试性类维生素类梯度在根中起作用，并将检查梯度与振荡的相互作用的假设。另外，LR形成的自然变化将用于识别此过程中涉及的基因。分析LR形成中振荡和梯度的主要方法是转基因植物中荧光素酶报道器的实时成像。通过化学和分子生物学方法，将检查振荡和随后形成LR的能力的响应。这些实验的结果将用于数学上模拟振荡的行为及其与梯度的相互作用。最后，通过结合研究和定量性状基因座的分析，将使用LR形成的自然变异来识别该过程中涉及的基因。这些研究构成了分析LR开发的一种新型方法，并将揭示有关如何建立和维护LR周期性的基本问题。