Elucidation and functional characterisation of different components of Caenorhabditis elegans immunity.

Analysing protein profiles of the ground nematode after infection with gram positive or negative bacteria resulted in the identification of 150 significantly up- or downregulated proteins. This project meant to further study their involvement in immunity. First, we will determine which proteins are present in immune tissues and further focus on this selection. We will order mutants with a deleted gene of interest and investigate their performance in different physiological assays (survival, egg-laying, food preference, pharyngeal pumping ). Second, we will measure the worms peptidome after infection with several pathogens. Such an antimicrobial peptidomics study was never done before and might yield new reporter genes. Third, we want to discover whether hypothetical transcription factors found in the 150 proteins play a role in specifically signalling the immune response. Therefore, we will construct a stable line of worms which produce a green protein whenever a given gene (reporter) is expressed. If we chose an antimicrobial peptide which is only expressed upon e.g. gram negative infection, worms will turn green only when exposed to gram negative bacteria. Via RNAi we can silence the gene of the putative transcription factor. Thus, losing green colour indicates the specific involvement in immune signalling.

Keywords:Differential peptidomics, Antimicrobial proteins, Antimicrobial peptides, Innate immunity, C. elegans

Disciplines:Animal biology, General biology