Fig. 2.

Coefficients of variation for protein PAI values between triplicate LC-MS measurements. The results are shown for experiments without fractionation (one gel band analyzed three times or three replicate gel bands analyzed once by LC-MS) or with one-dimensional SDS-PAGE fractionation (each of the 12 molecular weight fractions from one gel lane analyzed three times consecutively or analysis of three gel lanes). A, histogram of CVs distribution in the different experiments. B, box and whisker plots showing the dispersion of protein CVs near the median value. The bottoms and tops of the boxes correspond to the 25th and 75th percentiles of the CV distribution, and whiskers correspond to the lowest and highest values within 1.5× interquartile range of these limits. Extreme values falling out of the box plots correspond to outliers. C, number of proteins and quantitative repeatability in each experiment.