Vacuoles of diatoms

对动物、酵母和陆地植物的溶酶体和液泡进行了深入研究。在这些研究过程中，我们清楚地认识到，这些区室不仅仅具有分解活性，而且还参与许多细胞功能。从细胞生物学的角度来看，这些隔室的产生以及分子向液泡和溶酶体的运输代表了重要的问题，这些问题在最先进的方法中得到了深入的研究。最近的研究进展表明，这些模型在分子和功能上存在重大差异，这表明研究不同生物在这一主题中的重要性。在这个项目中，我们想要研究硅藻的液泡样结构。这些生物属于一个超群，染色质胚芽，这是关于液泡只初步研究。我们的初步工作支持这样的观点，即在这些单细胞生物中存在两种不同的液泡样结构，它们被认为至少具有储存脂质和聚糖的功能。但是，没有描述其他功能。我们用GFP与潜在的空泡膜蛋白融合的初步靶向实验表明，不同的结构可以被标记；其中一种确实是由光镜和电子显微镜结合技术显示的液泡样结构之一。此外，我们还建立了几个室特异性标记，这将对研究液泡样结构的靶向机制具有指示性。这些机制将以组合的方法进行研究，其中膜蛋白的靶向信号指向硅藻的两种不同的液泡样结构。此外，我们还想研究其中一个液泡样结构的起源。我们不仅期望从我们的工作中获得硅藻两种不同的液泡样结构的分子表征，而且还期望从分子可达的染色质微孔模型系统中对细胞内蛋白质靶向不同的基本特征区室的机制有新的见解。所有的发现将在进化的观点中并行研究，目的是提供硅藻进化的新方面。从长远来看，我们的工作可能会通过为重组蛋白或纤维提供新的储存空间来影响生物技术的应用。

Lysosomes and vacuoles of animals, yeast and land plants are intensively studied. In the course of these studies it became clear that these compartments have more than lytic activities and contribute to many cellular functions. From a cell biological view, the generation of these compartments and trafficking of molecules to vacuoles and lysosomes represent important issues, which are intensively studied in state-of-the-art approaches. Recent progress showed major molecular and functional differences between the models, indicating the importance of research on different organisms in this topic. In the proposed project we would like to investigate vacuolar-like structures in diatoms. These organisms belong to a supergroup, the chromalveolates, which is in respect to vacuoles only rudimentary studied. Our preliminary work supports the view that two different vacuolar-like structures are present in these unicellular organisms, which are supposed to have at least functions in storage of lipids and glycans. However, other functions are not described. Our initial targeting experiments with GFP fused to potential vacuolar membrane proteins showed that different structures can be labeled; one of these is indeed one of the vacuolar-like structures as showed by the combination of light and electron microscopically techniques. In addition we have established several compartment-specific markers, which will be indicative to study targeting mechanisms to vacuolar-like structures. These mechanisms will be studied in a combinatorial approach, in which the targeting signals of membrane proteins directed to the two different vacuolar-like structures of diatoms are studied. In addition we would like to investigate the origin of one of the vacuolar like structures. We expect from our work not only a molecular characterization of the two different vacuolar-like structures of a diatom, but also new insights into the mechanisms of intracellular protein targeting across the different, rudimentary characterized compartments in a molecular accessible chromalveolate model system. All of the findings will be studied in parallel in an evolutionary view with the aim to provide new aspects of the evolution of diatoms. Perspectively, our work might influence biotechnological applications by providing new storage compartments for recombinant proteins or fibers.