Melanson Jeremy E, Avery Steven L, Pinto Devanand M
Institute for Marine Biosciences, National Research Council of Canada, Halifax, Nova Scotia, Canada.
Proteomics. 2006 Aug;6(16):4466-74. doi: 10.1002/pmic.200600112.
Peptide dimethylation with isotopically coded formaldehydes was evaluated as a potential alternative to techniques such as the iTRAQ method for comparative proteomics. The isotopic labeling strategy and custom-designed protein quantitation software were tested using protein standards and then applied to measure proteins levels associated with Alzheimer's disease (AD). The method provided high accuracy (10% error), precision (14% RSD) and coverage (70%) when applied to the analysis of a standard solution of BSA by LC-MS/MS. The technique was then applied to measure protein abundance levels in brain tissue afflicted with AD relative to normal brain tissue. 2-D LC-MS analysis identified 548 unique proteins (p<0.05). Of these, 349 were quantified with two or more peptides that met the statistical criteria used in this study. Several classes of proteins exhibited significant changes in abundance. For example, elevated levels of antioxidant proteins and decreased levels of mitochondrial electron transport proteins were observed. The results demonstrate the utility of the labeling method for high-throughput quantitative analysis.
用同位素标记的甲醛进行肽二甲基化被评估为一种潜在的替代技术，可用于比较蛋白质组学，如iTRAQ方法。使用蛋白质标准品对同位素标记策略和定制设计的蛋白质定量软件进行了测试，然后将其应用于测量与阿尔茨海默病（AD）相关的蛋白质水平。当应用于通过LC-MS/MS分析BSA标准溶液时，该方法具有高精度（10%误差）、精密度（14%相对标准偏差）和覆盖率（70%）。然后将该技术应用于测量患有AD的脑组织相对于正常脑组织中的蛋白质丰度水平。二维LC-MS分析鉴定出548种独特蛋白质（p<0.05）。其中，349种蛋白质通过两条或更多符合本研究统计标准的肽进行了定量。几类蛋白质的丰度出现了显著变化。例如，观察到抗氧化蛋白水平升高，线粒体电子传递蛋白水平降低。结果证明了该标记方法在高通量定量分析中的实用性。
