Investigation of Murine Neural Progenitor Cell to NG2 Cell Differentiation by TMT based Quantitative Proteomics

摘要

We confirmed the differentiation of cells towards the oligodendroglial linage using neurospheres generated from NG2-YFP-knockin mice, in which YFP expression indicates conversion to NG2 cells by fluorescence microscopy. Five independent replicates of neurosphere differentiation were carried out and analyzed by LC-MS/MS. 6151 proteins were identified of which 5383 proteins could be quantified in all time points. Statistical tests were applied and significantly regulated proteins identified. After median normalization of TMT reporter ion intensities 863 proteins were found significantly upregulated at day 15 in comparison to day 0, whereof 297 proteins showed a log2 fold change greater than 1. We further determined 1079 proteins to be significantly downregulated, whereof 183 proteins were regulated more than 2-fold. At day 3 no significantly regulated proteins could be detected. We found oligodendrocyte specific marker proteins, such as myelin proteolipid protein (PLP1) or myelin basic protein (MBP) to be upregulated continuously, whereas e.g. Nestin, a marker for neural progenitor cells, was downregulated.