The chemical sense of marine isopod crustaceans

我们目前对甲壳类嗅觉通路的形态和化学引导行为的认识严重偏向十足纲的成员。在目前的项目中，我们希望通过分析外周和中枢嗅觉通路的结构以及进行行为分析，对软体动物甲壳类的另一个主要类群--海洋等足纲动物的嗅觉有更多的了解。为此，我们建议在广泛的等足类动物中使用神经解剖学方法分析触角和中央嗅觉通路的形态，如扫描电子显微镜、连续半薄切片结合3D重建、用神经元示踪剂填充触角、局部应用右旋糖苷标记嗅觉中间神经元群体，以及免疫荧光结合激光共聚焦扫描显微镜。我们将尝试分析来自不同栖息地的代表，包括深海、北极和南极洲、热带地区，以及来自不同生活方式的代表，包括食腐动物和寄生物种。此外，气味来源的嗅觉引导行为和导航策略将以波罗的海常见的杂食性等足目动物Saduria entomon为模型，在行为测试中进行测试。在神经系统学方法中，我们的数据将与其他软体动物甲壳类和六足类的嗅觉系统的形态进行比较，以便提取数据，以了解节肢动物嗅觉系统的一般进化。

Our current knowledge on both the morphology of the crustacean olfactory pathway and on chemically guided behavior is heavily biased towards members of the Decapoda. In the current project, we want to gain more insights into olfaction in another major group of malacostracan crustaceans, the marine Isopoda by analysing the architecture of the peripheral and central olfactory pathway and by conducting behavioral essays. To that end we propose here to analyze, in a wide range of isopods, the morphology of the antennae and the central olfactory pathway with neuroanatomical methods such as scanning electron microscopy, serial semithin sectioning combined with 3D reconstruction, antennal backfilling with neuronal tracers, focal application of dextrans to label populations of olfactory interneurons, and immuno-fluorescence combined with confocal laser-scan microscopy. We will try to analyse representatives from a wide range of different habitats including the deep sea, the Arctic and Antartica, the Tropics, and from different life styles including scavengers and parasitic species. Furthermore, olfactory-guided beha-vior and navigation strategies to odor sources will be tested in behavioral assays using the omnivorous isopod Saduria entomon which is common in the Baltic as a model. In a neurophylogenetic approach, our data will be compared to the morphology of the olfactory systems in other malacostracan crustaceans and hexapods in order to extract data for understanding the evolution of arthropod olfactory systems in general.