The protein phosphatses of arabidopsis thaliana: bioinformatics, biochemistry and function

拟南芥蛋白磷酸盐：生物信息学、生物化学和功能

• 批准号: 216895-2008
• 负责人: Moorhead, Gregory
• 金额: $ 4.01万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2010
• 资助国家: 加拿大
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=454015
• 关键词: protein; phosphatses; arabidopsis; thaliana; bioinformatics

My research program focuses on a group of highly conserved enzymes (proteins) called protein phosphatases. Most cellular proteins get modified in the cell in very specific ways to allow control of their function in response to signals from outside or within the cell. The most common means of modifying a protein is the covalent attachment of a phosphate group. This is referred to as protein phosphorylation and the enzymes that add this phosphate are called protein kinases and the enzymes that remove this phosphate are protein phosphatases. My group works with the model plant Arabidopsis thaliana and by using the publicly available genome sequence data and information from other well characterized organisms (like humans and yeast) we have identified a complete set of protein phosphatases in this organism. By examining the amino acid sequence of these protein phosphatases we have been able to predict certain features for several of these enzymes and we are now doing the biochemistry and cell biology to further define the properties and role of these enzymes. My group is focusing on the type one phosphatases (PP1), which are regulated by targeting subunits that define their function. As yet, no targeting subunits are known in plants. Using affinity chromatography and mass spectrometry we have identified 20 binding proteins and propose to perform a detailed characterization for 3 of them, including the putative nucleoside kinase ZAP3. Through bioinformatic insights we have also focused our attention on a completely novel chloroplast localized phosphatase. This enzyme is being characterized and we believe it may represent an ancient or ancestral form of the type one or 2A phosphatases. By using affinity chromatography and mass spectrometry as a starting point, we have also identified a type 2A (PP2A) complex that interacts with several other cellular proteins and plays a role in controlling the trafficking of protein cargo in the cell. My research program is making the critical bridge between computer-based observations (bioinformatics) and the biochemistry, molecular and cell biology necessary to support these observations.

我的研究项目专注于一组高度保守的酶(蛋白质)，称为蛋白磷酸酶。大多数细胞蛋白质在细胞中以非常特殊的方式进行修饰，以允许控制其功能，以响应来自细胞外或细胞内的信号。最常见的修饰蛋白质的方法是磷酸基团的共价连接。这被称为蛋白质磷酸化，添加这种磷酸盐的酶称为蛋白质激酶，而去除这种磷酸盐的酶称为蛋白质磷酸酶。我的团队以模式植物拟南芥为研究对象，通过使用公开的基因组序列数据和来自其他特征良好的生物(如人类和酵母)的信息，我们已经在这种生物中鉴定了一套完整的蛋白质磷酸酶。通过研究这些蛋白磷酸酶的氨基酸序列，我们已经能够预测其中几种酶的某些特征，我们现在正在进行生物化学和细胞生物学，以进一步确定这些酶的性质和作用。我的团队专注于第一型磷酸酶(PP1)，它通过靶向定义其功能的亚基来调节。到目前为止，在植物中还没有已知的靶向亚基。利用亲和层析和质谱法，我们已经鉴定了20个结合蛋白，并建议对其中3个蛋白进行详细的表征，其中包括推测的核苷激酶ZAP3。通过生物信息学的洞察，我们还将注意力集中在一种全新的叶绿体定位的磷酸酶上。这种酶的特征是，我们认为它可能代表了一种古老的或祖先形式的类型1或2A型磷酸酶。通过使用亲和层析和质谱学作为起点，我们还鉴定了一种2A型(PP2A)复合体，它与其他几种细胞蛋白相互作用，并在控制蛋白质货物在细胞内的运输方面发挥作用。我的研究计划是在基于计算机的观察(生物信息学)和支持这些观察所必需的生物化学、分子和细胞生物学之间架起关键的桥梁。