Characterization of the circadian clock in Nannochloropsis oceanica

【摘要】生物钟是周期约为24小时的分子振荡器。陆地植物利用它们的生物钟和光信号之间的相互作用来预测每日和季节的变化。然而，人们对光质量和生物钟如何揭示海洋生态系统中的时间、季节和深度信息知之甚少。本项目的目的是研究海洋微藻纳米绿藻的生物钟。目前，洋洲海葵被用作omega-3脂肪酸的来源，由于其高脂含量，正被研究作为生物燃料的潜在来源。大洋洋藻属于层桩纲，这是一种非常多样化的次生内共生生物，包括硅藻和植物病原体，如藻门。虽然生物钟已经在动物、植物、真菌和细菌中进行了研究，但目前尚不清楚调节层堆生物昼夜节律的分子机制。作为该项目的一部分，PI的实验室将开始识别昼夜节律钟的分子组成部分，并表征海洋生物的光信号和昼夜节律之间的相互作用。这些研究将促进我们对昼夜节律振荡器进化的认识，并为理解昼夜节律在浮游植物生理中的作用提供一个分子框架。除了培养研究生外，PI还将为计划成为中学教师的本科生提供实验室研究经验。这些学生也将有机会发展自己的实验教学单元。

ABSTRACTCircadian clocks are molecular oscillators with a period of about 24-h. Land plants use the interaction between their circadian clock and light signals to predict daily and seasonal changes. However, little is known on how light quality and the circadian clock reveal time, seasonal, and depth information in the marine ecosystem. The goal of this project is to study the circadian clock of the marine microalga Nannochloropsis oceanica. N. oceanica is currently used as a source of omega-3-fatty acids and due to its high lipid content is being investigated as a potential source of biofuel. N. oceanica belongs to the Stramenopiles a very diverse group of secondary endosymbionts that includes diatoms and plant pathogens such as Phytophtora. Although circadian clocks have been studied in animals, plants, fungi and bacteria, nothing is currently known about the molecular mechanisms regulating the circadian rhythms of Stramenopiles. As part of this project the PI's laboratory will start to identify the molecular components of the circadian clock and characterize the interaction between light signals and circadian rhythms in N. oceanica. These studies will advance our knowledge on the evolution of circadian oscillators, and provide a molecular framework to understand the role of circadian rhythms in phytoplankton physiology. In addition of training graduate students, the PI will provide laboratory research experience for undergraduate students planning to become secondary school teachers. These students will also have the opportunity to develop their own laboratory-teaching units.