CAREER: Engineering principles within cell-cell communication networks in animal development

1254344 reeves细胞间信号的调控在生物学的许多领域都是至关重要的，包括发育、干细胞生物学和成体组织的适当维持。在发育过程中，组织的模式是由远距离的，但高度可变的信号，直接在不同的位置基因表达的差异。在首席研究员的实验室中，首要目标是将工程原理与调节机制联系起来，以确保在面对高度可变的细胞间信号时可靠的基因表达模式。提出的工作旨在研究生物调节机制中工程原理的两个具体实例：反馈控制和噪声过滤。果蝇黑腹果蝇（Drosophila melanogaster）被用作模式生物，因为它在所需的复杂性（作为多细胞生物）和易于操作之间取得了平衡，拥有先进的遗传和转基因工具包。在果蝇胚胎早期（1-3小时），背腹轴由转录因子Dorsal形成。在之前的工作中，研究人员发现，即使面对高内在噪声和外在变异性，Dorsal也能建立稳健的基因表达模式。负反馈与次要信号通路，骨形态发生蛋白（BMP）通路的相互作用，被假设为增加基因表达模式在背侧信号变化方面的稳健性。此外，背侧靶基因的表达位置远远超出了信号分子的空间梯度预期可靠起作用的位置。因此，将研究噪声最高的背侧信号尾部基因表达的噪声过滤能力。负反馈相互作用和噪声过滤将使用遗传和转基因操作、基因表达输出的定量（实时）成像/模型、定量实时PCR和定量Western Blot进行研究。与提出的实验研究相关，外展目标是通过强调生物系统中发现的工程原理的教育材料，促进工程和生物学之间的协同作用。将与NCSU负责监督K-12外展的科学之家（Science House）合作开发并传播一个面向高中生的丰富模块。目标是培养未来的生物专业学生，在初中和高中阶段，熟悉工程和物理的语言和观点。在学院授课的本科生将作为助教参加。在研究生阶段，在NCSU远程教育计划的帮助下，将广泛传播一门特别主题课程，重点关注组织图案的工程原理。这些教材，连同研究工作，将提供一个视角和研究，以了解和利用？自然的工程?存在于生物系统中的

1254344ReevesRegulation of signaling between cells is crucial in many areas of biology, including development, stem cell biology, and proper maintenance of adult tissues. In development, tissues are patterned by long range, yet highly variable signals that direct differences in gene expression at different locations. In the Principal Investigator's lab, the overarching goal is to connect engineering principles to the regulatory mechanisms that ensure reliable gene expression patterns in the face of highly variable intercellular signals. The proposed work aims to study two specific instances of engineering principles in biological regulatory mechanisms: feedback control and noise-filtering. The fruit fly Drosophila melanogaster is used as a model organism, as it strikes a balance between the complexity needed (as a multicellular organism) and ease of manipulation, with advanced genetic and transgenesis toolkits. In the early (1-3 hours old) Drosophila embryo, the dorsal-ventral axis is patterned by the transcription factor Dorsal. In previous work, it was found that Dorsal establishes robust gene expression patterns even in the face of high intrinsic noise and extrinsic variability. Negative feedback interactions with a secondary signaling pathway, the Bone Morphogenetic Protein (BMP) pathway, are hypothesized to increase the robustness of gene expression patterns with respect to variations in Dorsal signaling. Furthermore, dorsal target genes are expressed in a location far beyond the point in which a spatial gradient of a signaling molecule is expected to reliably act. Thus, the noise-filtering capabilities of gene expression in the tail of Dorsal signaling, where noise is the highest, will be investigated. Both negative feedback interactions and noise-filtering will be studied using genetic and transgenic manipulations, quantitative (live) imaging/models of gene expression outputs, quantitative real-time PCR and quantitative Western Blot.Related to the proposed experimental studies, the outreach goal is to facilitate the synergy between engineering and biology through educational materials that highlight the engineering principles found in biological systems. An enrichment module for high school students will be developed and disseminated in partnership with the Science House, an NCSU organization that oversees K-12 outreach. The goal is to train future biology majors, at the high school junior and senior level, to be comfortable with the language and viewpoint of engineering and physics. Undergraduate students in courses taught by the PI will participate as teaching assistants. At the graduate level, a special topics course that focuses on the engineering principles in tissue patterning will be broadly disseminated with the help of the NCSU Distance Education Program. These educational materials, together with the research work, will provide the perspective and research to understand and then utilize the ?natural engineering? present in biological systems.