Trafficking of Silaffins and Cingulins and Quantification of Underlying Transport Mechanisms

硅藻是一类单细胞光养生物。这些生态上非常重要的生物体的细胞标志之一是它们的硅基细胞壁。对于这里提出的工作的模式生物海链藻，基因组数据以及操纵基因组和基因表达的分子工具已经很好地建立起来。这使得能够在体内研究参与二氧化硅生成的蛋白质，例如silaffins，cingulins或silacidins。在这里，我们将调查三个代表的silaffin和cingulin家庭的目标。这些蛋白质位于细胞壁的不同部分（瓣膜或环带），并将研究负责的分子信号。鉴定后，将研究信号将阀蛋白重定向到环带中的能力，反之亦然，这是重新设计硅藻细胞壁的重要一步。为了揭示细胞内运输细胞壁生成因子的细胞机制，我们将研究标记蛋白，这是预计将成为这一过程的一部分，在蛋白质组学方法。平行的顺式作用序列参与硅诱导的转录调控将进行分析。总而言之，我们的计划将突出有机基质成分到达硅藻的二氧化硅细胞壁所需的靶向机制。

Diatoms are a group of unicellular phototrophs. One of the cellular hallmarks of these ecologically very important organisms is their silica based cell wall. For Thalassiosira pseudonana, the model organism for the work that is proposed here, genomic data as well as molecular tools for manipulating the genome and expression of genes are well established. This has enabled to study proteins involved in silica generation, such as silaffins, cingulins or silacidins, in vivo. Here we shall to investigate the targeting of three representatives of the silaffin and cingulin families. These proteins are located in different parts of the cell wall (either valve or girdle band) and the molecular signals responsible for that will be studied. After identification, the signals will be investigated for their capacity to redirect a valve protein into the girdle band and vice versa, which is an important step to re-design the cell wall of diatoms. To reveal the cellular machinery for intracellular trafficking of cell wall generation factors, we will study marker proteins, which are expected to be part of this process, in a proteomics approach. In parallel cis-acting sequences involved in silicon-induced transcriptional regulation will be analyzed. Altogether, our programme will highlight the targeting mechanisms of organic matrix components required to reach the silica cell wall of diatoms.