Nutrient regulation of Alternative splicing and transcription by O-GlcNAcylation

这个项目的长期目标是了解控制基因的分子机制。 表达和发育转变。虽然转录已经得到了广泛的研究，但 RNA选择性剪接的转录后机制尽管有许多 在细胞调节、人类健康和植物生长发育方面的重要性。我们有 发现拟南芥蛋白AtAcinus在进化上与之相关，但与 在转录调控中起重要作用的人腺泡蛋白，RNA替代 剪接和细胞凋亡。我们未发表的研究表明，AtAcinus被O-修饰。 GlcN酰化在许多基因的选择性剪接中起着至关重要的作用，其中许多基因 编码信号和发育途径的关键组成部分。特别是，我们的数据表明 黄曲霉在调节种子萌发和开花这两个主要方面发挥着重要作用 植物的发育转变。使用蛋白质组学、遗传学、基因组学和 在拟南芥模型系统中的生化方法，我们在以下方面取得了巨大进展 了解AtAcinus的功能。我们的结果支持了AtAcinus被控制的假设 通过O-GlcN酰化反应对内源和环境提示做出反应，进而调节关键 通过转录和转录后机制的细胞通路。在这份提案中， 我们计划继续使用蛋白质组、基因组和遗传方法的组合来进一步 促进我们对腺泡调节途径的理解。我们将1)剖析分子的功能 AtAcinus，特别是利用邻近标记、交联质谱学和 生化分离、CLIP-SEQ和CLIP-MS技术以了解AtAcinus是如何携带的 提出了多种功能(目标1和3)；2)剖析了AtAcinus功能是如何由POST- 翻译修改(目标2)。这项提案中概述的实验将大大推进 我们对RNA选择性剪接和O-GlcN酰化分子机制的理解 转录后水平的信号整合机制。考虑到进化中的 因此，本研究不仅对植物生物学和农业具有重要意义，而且还可以 潜在地帮助我们理解信号和细胞调节的基本机制 广泛相关。

The long-term goal of this project is to understand the molecular mechanisms that control gene expression and developmental transitions. While transcription has been extensively studied, the posttranscriptional mechanisms of RNA alternative splicing is much less understood despite of their importance in cellular regulation, human health, and plant growth and development. We have discovered that the Arabidopsis protein AtAcinus is evolutionarily related to but highly divergent from the human Acinus protein, which plays important roles in regulating transcription, RNA alternative splicing, and apoptosis. Our unpublished studies have shown that AtAcinus is modified by O- GlcNAcylation, plays essential role in alternative splicing of a number of genes, many of which encoding key components of signaling and developmental pathways. In particular, our data indicate that AtAcinus play important roles in regulating seed germination and flowering, two major developmental transition in plants. Using a combination of proteomics, genetics, genomic and biochemical approaches in the Arabidopsis model system, we have made tremendous progress in understanding the functions of AtAcinus. Our results support a hypothesis that AtAcinus is controlled by O-GlcNAcylation in response to endogenous and environmental cues, and in turn it regulates key cellular pathways through both transcriptional and posttranscriptional mechanisms. In this proposal, we plan to continue using the combination of proteomic, genomic and genetic approaches to further advance our understanding of Acinus regulatory pathway. We will 1) dissect the molecular functions of AtAcinus, particularly taking advantage of proximity labeling, cross-linking mass spectrometry and biochemical fractionation, CLIP-seq and CLIP-MS technologies to understand how AtAcinus carries out multiple functions (aim 1 and 3); 2) dissect how AtAcinus functions are regulated by post- translational modifications (aim 2). The experiments outlined in this proposal will greatly advance our understanding of the molecular mechanism of RNA alternatively splicing and O-GlcNAcylation and the mechanisms of signal integration at post-transcriptional level. Given the evolutionary conservation of Acinus, this study not only is important for plant biology and agriculture, but also can potentially help us understand fundamental mechanisms of signaling and cellular regulation that are relevant broadly.