Investigation of novel polar lipid signals in planktonic interactions

浮游植物贡献了全球约一半的初级生产量，它们与浮游动物的捕食者-猎物相互作用支撑着整个远洋食物网。然而，调节这些相互作用的化学信号在很大程度上是未知的。最近，Erik Selander的研究小组发现，在海洋浮游动物捕食者和浮游植物物种(如有害的藻华形成属亚历山大藻)之间的相互作用中，桡足类化合物是已知的第一组化学信号。然而，这些化合物的全部功能以及浮游植物对桡足胺的感知仍不清楚。拟议的研究项目将侧重于两个主要目标。第一个目标将是确定其他新的聚足咪胺信号化合物及其桡足类物种特有的模式。为此目的，将使用一套广泛的化学分离和检测技术。主办研究所拥有独特的设备、设施和支持该项目的技术诀窍，包括化学生态学和核磁共振技术方面的培训。第二个目标是鉴定浮游植物塔玛亚历山大藻和马里诺骨骼藻中的共扑虫胺受体蛋白。受体的识别将通过不同的方法来实现。与美国亚特兰大佐治亚理工学院的Julia Kubanek小组合作，将使用基于细胞的分析和电生理学的组合。为了学习所需的方法，计划参观Julia Kubanek的小组。此外，噬菌体展示和蛋白亲和层析将被用来鉴定参与感知粘虫胺的受体蛋白及其基因组序列。浮游动物和浮游植物之间的捕食相互作用对远洋生态系统的生态平衡至关重要，这些相互作用主要受化学信号的调节。对这些信号及其受体蛋白的识别将有助于更深入地了解浮游生物之间的相互作用。此外，拟议的研究项目有可能成为一块罗塞塔石头，用于破译公海上有影响力但尚不为人所知的化学语言。

Phytoplankton contributes to about half of the global primary production and their predator - prey interactions with zooplankton underpin the entire pelagic food web. Yet, the chemical signals that mediate these interactions are largely unknown. Recently, the group of Erik Selander identified copepodamides as the first known group of chemical signals in the interaction of copepods as marine zooplankton predators and phytoplankton species like the harmful algal bloom forming genus Alexandrium. However, the entire function of these compounds as well as the sensing of copepodamides by phytoplankton is still unknown. The proposed research project will focus on two main objectives. The first objective will be the identification of additional novel copepodamide signalling compounds and their copepod species-specific patterns. For this purpose a broad set of chemical separation and detection techniques will be used. The host institute has a unique combination of equipment, facilities, and the know how to support the project, including training in chemical ecology and NMR techniques. The second objective is the identification of copepodamide receptor proteins in the phytoplankton species Alexandrium tamarense and Skeletonema marinoi. The receptor identification will be achieved by different approaches. In cooperation with the group of Julia Kubanek (Georgia Tech, Atlanta, USA), a combination of cell-based assays and electrophysiology will be used. To learn the required methods, a visit at the group of Julia Kubanek is planned. Further, phage display and protein affinity chromatography will be applied to identify the receptor proteins involved in copepodamide perception and their genomic sequence.The predator prey interaction between zooplankton and phytoplankton is crucial for the ecological balance of the pelagic ecosystem and these interactions are mainly regulated by chemical signalling. The identification of these signals and their receptor proteins will lead to a deeper understanding of planktonic interactions. Furthermore, the proposed research project has the potential to act as a Rosetta stone for the deciphering of the influential, but yet unknown chemical language of the open oceans.