Novel Mass Spectrometer for Comprhensive No-Loss MS/MS of All Stored Ions

描述(由申请人提供)：人类基因组计划激发了高通量技术的重大进步，用于研究基因表达中的功能和激活。然而，为了真正解决疾病，必须了解与mRNA和蛋白质组水平的基因表达相关的变化。自后基因组时代以来，蛋白质组学领域--在特定条件下对蛋白质的系统分析，如疾病状态与健康状态--有了巨大的发展。蛋白质组学的主要问题之一是在复杂的生物混合物中，如磷蛋白中，低丰度的反式修饰蛋白质。这就需要强大和高灵敏度的检测系统，其中质谱仪(MS)由于其快速的实验时间和灵敏度而逐渐成为这些分析的选择方法。这项提议的长期目标是开发一种超灵敏的离子陷阱质谱学技术，以常规地对复杂的生物混合物进行全面的MS/MS分析。这一发展的关键是能够监测离子陷阱中存储的所有离子，而不丢弃任何离子，这通常是在标准蛋白质组学实验中完成的。这项提议的具体目的是：(1)通过隔离离子陷阱内的压力，使我们能够在仪器的不同区域使用最佳气体，从而优化最近建造的高容量离子陷阱仪器：高容量离子陷阱中的氦，离子源冷却区中的氮气，以及碰撞池中的氮气或氩。此外，我们还将修改大容量离子陷阱的几何形状，以提高仪器的分辨率。这些直截了当的改进有望进一步提高大容量离子陷阱仪器的性能。(2)下一阶段的研究将把一个正交注入反射顶质谱计耦合到大容量离子陷阱上。(3)用这种新型的大容量离子陷阱顶端质谱仪进行样品的综合分析，为今后的实验做准备。蛋白质磷酸化水平的异常与癌症、糖尿病和类风湿性关节炎等重大疾病有关。识别和研究这些磷酸化过程的能力最终将使我们离找到治愈方法更近一步。

DESCRIPTION (provided by applicant): The human genome project has inspired significant advancements in high-throughput technologies for the study of function and activation in gene expression. However, in order to truly tackle disease, the changes associated with gene expression at the mRNA and proteome levels has to be understood. Since the post-genomic era, the field of proteomics-the systematic profiling of proteins under a given set of conditions such as diseased versus healthy state- has grown tremendously. One of the major problems of proteomics is the low abundance of post-trans la tiona I ly modified proteins in complex biological mixtures such as phosphoproteins. This mandates a need for robust and highly sensitive detection system in which mass spectrometry (MS) has evolved as the method of choice for these analyses due to its fast experimental timescales and sensitivity. The long term goal of this proposal is to develop an ultra-sensitive ion trap mass spectrometry technique to routinely carry out comprehensive MS/MS analysis of complex biological mixtures. The key to this development is the ability to monitor all ions that are stored in an ion trap without discarding any, which is typically done in a standard proteomics experiment. The specific aims of this proposal are to: (1) Optimize the recently constructed high-capacity ion trap instrument by isolating the pressure within the ion trap to allow us to use optimal gases in the various regions of the instrument: helium in the high-capacity ion trap, N2 in the ion source cooling region, and N2 or argon in the collision cell. In addition, we will modify the geometry of the high-capacity ion trap to increase the resolution of the instrument. These straightforward improvements are expected to further enhance the performance of the high-capacity ion trap instrument. (2) The next phase of the research will couple an orthogonal injection reflectron TOP mass analyzer to the high-capacity ion trap. (3) Finally, future experiments will be geared towards the comprehensve sample analysis using this new high-capacity ion trap TOP MS instrument. Abnormal levels of protein phosphorylation are known to be associated with major diseases such as cancer, diabetes, and rheumatoid arthritis. The ability to identify and study these phosphorylation processes will ultimately bring us a step closer to finding a cure.