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mRNA和蛋白质组水平上与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-在给定的条件下（如疾病与健康状态）对蛋白质进行系统分析-已经取得了巨大的发展。蛋白质组学的主要问题之一是在复杂的生物混合物如磷蛋白中低丰度的翻译后修饰的蛋白质。这要求需要稳健且高灵敏度的检测系统，其中质谱法（MS）由于其快速的实验时间尺度和灵敏度而发展为这些分析的选择方法。该提案的长期目标是开发一种超灵敏的离子阱质谱技术，以常规地对复杂的生物混合物进行全面的MS/MS分析。这种发展的关键是能够监测存储在离子阱中的所有离子而不丢弃任何离子，这通常在标准蛋白质组学实验中完成。本提案的具体目标是：（1）通过隔离离子阱内的压力来优化最近构建的高容量离子阱仪器，以允许我们在仪器的各个区域中使用最佳气体：高容量离子阱中的氦气，离子源冷却区域中的N2，以及碰撞室中的N2或氩气。此外，我们将修改高容量离子阱的几何形状，以增加仪器的分辨率。这些简单的改进有望进一步提高高容量离子阱仪器的性能。(2)研究的下一阶段将把一个正交注入反射TOP质量分析仪耦合到高容量离子阱上。(3)最后，未来的实验将面向使用这种新的高容量离子阱TOP MS仪器进行全面的样品分析。已知蛋白质磷酸化水平异常与癌症、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将最终使我们更接近找到治愈方法。

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.