Contemporary proteomics requires prompt and confident protein identification of proteins of interest. The ability to utilize animal models to study the biochemical correlates of human disease requires a more complete database of those species as a prerequisite. To this end, the de novo sequencing strategy presented here provides a rapid and reliable means to identify proteins in Macaca mulatta – a species for which publicly available protein databases are very limited. However, it is important to note that this strategy is generalizable to other tissues, protein preparations and species and is not exclusive for Macaca mulatta or for cytosolic protein fractions from brain.
From 30 excised gel spots 13 were identified by mass spectrometry coupled with PEAKS de novo analysis software. Among the proteins were receptor-associated proteins, proteins involved in intra-cellular signaling, cytoskeletal structure, protein folding, hormonal changes and regulation of oxidative stress. The current study was undertaken to delineate a preliminary proteomics scale methodology to identify proteins de novo from NAc cytosol in the primate brain. Following mass spectrometric analysis, the most abundant peptides in the mixture led to the most accurate protein identification – hence, less abundant proteins may be overlooked. However, this caveat holds for all two dimensional gel-based proteomic approaches for studying disease states. Nevertheless, the present results provide the first preliminary de novo proteomic profile from Macaca mulatta and will form the basis of the future proteomics scale studies using non-human primate.