Proteomics of Brain Endothelium: Separation of Proteins by Two-Dimensional Gel Electrophoresis and Identification by Mass Spectrometry

The first complete deoxyribonucleic acid (DNA) sequence of an organism was published in 1977 (1 ), marking a starting point for what is today called genomics. In the meantime, there was a rapid development in scientific equipment and data processing capabilities, which led to a strong acceleration in the aquisition of knowledge on DNA sequences. There is no doubt that the sequencing of the human genome was one of the most important driving forces in that development. Based on the DNA sequence information, the next step is to determine the cellular expression levels of all genes and the expression of the complete set of proteins within a cell. The proteomics approach represents a further challenge for the completion of our knowledge on the molecular composition of cells.