EAGER: Environmental signals in a marine diatom

硅藻是一种微观水生生物，它们共同负责地球上约20%的光合作用。然而，人们对这些重要生物对环境变化的反应知之甚少。 该项目的主要目标是了解这些生物体如何感知环境并改变其生理机能以优化其生长和生产力。本项目将开发对研究领域具有广泛价值的重要新工具，并将阐明环境变化影响细胞生理学的机制。它将为本科生提供研究机会，并促进公共科学教育。本项目将阐明简单的环境信号如何导致模式海洋硅藻三角褐指藻的快速和可逆的生理反应。促进这些反应的信号转导途径几乎是未知的。 该假设将被测试，逆行信号发出的电子传递系统中的质体是硅藻翻译环境信号到核基因表达的主要手段，导致可逆的生理反应。基于生物信息学分析，反向遗传学方法将首先用于靶向假设代表硅藻中逆行信号转导系统的主要组分的五个基因。该项目将利用一种基于CRISPR/Cas9技术的快速而强大的基因编辑方法，结合一种基于自加工核酶序列的技术，该核酶序列位于指导RNA的侧翼，以靶向编码推定信号转导蛋白的基因。

Diatoms are microscopic aquatic organisms that are collectively responsible for approximately 20% of the photosynthetic activity on Earth. However, little is known of the response of these important organisms to changes in their environment. The primary goal of this project is to understand how these organisms sense the environment and alter their physiology to optimize their growth and productivity. This project will develop important novel tools that are anticipated to be of broad value to the research field, and will elucidate the mechanisms by which changes in the environment influence cell physiology. It will provide research opportunities for undergraduates and advance public science education. This project will elucidate how simple environmental signals lead to rapid and reversible physiological responses in a model marine diatom Phaeodactylum tricornutum. The signal transduction pathways that facilitate these responses are virtually unknown. The hypothesis will be tested that retrograde signals emanating from the electron transport system in the plastid are the primary means by which diatoms translate environmental signals into nuclear gene expression, leading to reversible physiological responses. Based on a bioinformatics analysis, a reverse genetics approach will initially be used to target five genes hypothesized to represent major components of the retrograde signal transduction system in diatoms. The project will utilize a rapid and robust gene-editing approach based on CRISPR/Cas9 technology, combined with a technique based on self-processing ribozyme sequences that flank the guide RNA to target the genes encoding the putative signal transduction proteins.