A meta-analysis of two-dimensional electrophoresis pattern of the Parkinson's disease-related protein DJ-1.

Abstract

The two-dimensional electrophoresis (2-DE) pattern of proteins is thought to be specifically related to the physiological or pathological condition at the moment of sample preparation. On this ground, most proteomic studies move to identify specific hallmarks for a number of different conditions. However, the information arising from these investigations is often incomplete due to inherent limitations of the technique, to extensive protein post-translational modifications and sometimes to the paucity of available samples. The meta-analysis of proteomic data can provide valuable information pertinent to various biological processes that otherwise remains hidden. Here, we show a meta-analysis of the PD protein DJ-1 in heterogeneous 2-DE experiments. The protein was shown to segregate into specific clusters associated with defined conditions. Interestingly, the DJ-1 pool from neural tissues displayed a specific and characteristic molecular weight and isoelectric point pattern. Moreover, changes in this pattern have been related to neurodegenerative processes and aging. These results were experimentally validated on human brain specimens from control subjects and PD patients. ImageJ is a public domain image processing program developed by the National Institutes of Health and is freely available at http://rsbweb.nih.gov/ij. All the ImageJ macros used in this study are available as supplementary material and upon request at info@biodigitalvalley.com. XLSTAT can be purchased online at http://www.xlstat.com/en/home/ at a current cost of approximately 300 EUR.