Callister Stephen J, Barry Richard C, Adkins Joshua N, Johnson Ethan T, Qian Wei-Jun, Webb-Robertson Bobbie-Jo M, Smith Richard D, Lipton Mary S
Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352, USA.
J Proteome Res. 2006 Feb;5(2):277-86. doi: 10.1021/pr050300l.
Central tendency, linear regression, locally weighted regression, and quantile techniques were investigated for normalization of peptide abundance measurements obtained from high-throughput liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry (LC-FTICR MS). Arbitrary abundances of peptides were obtained from three sample sets, including a standard protein sample, two Deinococcus radiodurans samples taken from different growth phases, and two mouse striatum samples from control and methamphetamine-stressed mice (strain C57BL/6). The selected normalization techniques were evaluated in both the absence and presence of biological variability by estimating extraneous variability prior to and following normalization. Prior to normalization, replicate runs from each sample set were observed to be statistically different, while following normalization replicate runs were no longer statistically different. Although all techniques reduced systematic bias to some degree, assigned ranks among the techniques revealed that for most LC-FTICR-MS analyses linear regression normalization ranked either first or second. However, the lack of a definitive trend among the techniques suggested the need for additional investigation into adapting normalization approaches for label-free proteomics. Nevertheless, this study serves as an important step for evaluating approaches that address systematic biases related to relative quantification and label-free proteomics.
研究了中心趋势、线性回归、局部加权回归和分位数技术,用于对通过高通量液相色谱-傅里叶变换离子回旋共振质谱(LC-FTICR MS)获得的肽丰度测量值进行归一化。从三个样本集获得了肽的任意丰度,包括一个标准蛋白质样本、两个取自不同生长阶段的耐辐射球菌样本,以及两个来自对照小鼠和甲基苯丙胺应激小鼠(C57BL/6品系)的小鼠纹状体样本。通过在归一化之前和之后估计无关变异,在有无生物变异的情况下对所选的归一化技术进行了评估。在归一化之前,观察到每个样本集的重复运行在统计学上是不同的,而在归一化之后,重复运行在统计学上不再不同。尽管所有技术都在一定程度上降低了系统偏差,但各技术之间的排名显示,对于大多数LC-FTICR-MS分析,线性回归归一化排名第一或第二。然而,这些技术之间缺乏明确的趋势表明,需要对适用于无标记蛋白质组学的归一化方法进行进一步研究。尽管如此,本研究是评估解决与相对定量和无标记蛋白质组学相关的系统偏差的方法的重要一步。