Swiss TPH

To date, we still know very little about the molecules and specific processes that determine Plasmodium gene expression, nuclear biology and genome function. A roadblock to a better understanding of this biology in Plasmodium has been the absence of identifiable orthologues of proteins known to govern these roles in better characterised model eukaryotes, and the inability to identify nuclear proteins by other means. In collaboration with Stuart Ralph (Melbourne University, Melbourne, Australia) and Paul Jenoe (Biozentrum, Basel, Switzerland) we have addressed this significant obstacle by producing a comprehensive survey of the proteome of purified P. falciparum nuclei based on high accuracy tandem mass spectrometry (Oehring and Woodcroft et al., submitted). This analysis identified hundreds of novel nuclear proteins in Plasmodium. We have thoroughly validated this dataset by informatic means and experimentally by immuno-localising more than twenty new nuclear proteins in transgenic parasites expressing epitope-tagged proteins. These subcellular localisations alone dramatically increase our population of known nuclear proteins in Plasmodium, and the transgenic lines generated here provide excellent tools to study the function of novel nuclear factors in detail. We also identified several novel transcription factor-associated peptide motifs, discovered several new regulatory factors, nucleolus-associated proteins, as well as proteins that may be involved in cell cycle-specific nuclear processes. We believe our dataset will prove to be a useful resource for further analyses of various aspects of nuclear biology in Plasmodium and other apicomplexan parasites.