Post-transcriptional control of slam in early Drosophila embryos

基因表达在很大程度上受转录水平的控制。近年来，许多mrna都受到转录后调控，如翻译的时空调控和特定的亚细胞定位。在特定的细胞质RNA蛋白复合物中发现了许多mrna，其功能在很大程度上是未知的。我们以果蝇早期胚胎中必不可少的基因“slam”为例，探讨其转录后调控机制。slam的特殊之处在于slam mRNA共定位于基域，与自身编码的蛋白结合并在功能上相互作用。该蛋白能够独立于RNA进行定位，并被认为可以招募slam RNA进行局部翻译。本项目将通过定位、高效翻译和RNA-蛋白质相互作用所需的RNA和蛋白质上的位点图谱，分析slam蛋白和RNA之间功能相互作用的机制。通过具体的报告结构，我们将揭示第一轮翻译的时空模式和新生肽的出现。此外，我们将分析翻译调控的候选基因，即FMR1和Caprin。这两个基因都产生了与弱slam等位基因相似的突变表型，表明其功能与slam有关。

Gene expression is largely controlled on the level of transcription. During recent years, it has become evident that many mRNAs are subject to posttranscriptional regulation, such as spatiotemporal regulation of translation and specific subcellular localization. Many mRNAs have been found in specific cytoplasmic RNA protein complexes, whose functions are largely unknown. We investigate mechanism of posttranscriptional regulation in the early Drosophila embryo with the essential gene “slam” as an example. slam is special in that slam mRNA co-localizes at the basal domain, binds to and functionally interacts with its own encoded protein. The protein is able to localize independent of the RNA and is assumed to recruit slam RNA for local translation. With the proposed research project, the mechanism of the functional interaction between slam Protein and RNA will be analyzed by mapping of the sites on RNA and protein required for localization, for efficient translation and for RNA-protein interaction. With specific reporter constructs we will reveal the spatio-temporal pattern of the first round of translation and appearance of nascent peptides. Furthermore, we will analyze candidate genes for translational regulation, i. e. FMR1 and Caprin. Both genes give rise to a mutant phenotype comparable to weak slam alleles, suggesting a function related to slam.