[
European Worm Meeting,
2006]
Katrin Hsken and Rudolf E. Leube. Besides actin filaments and microtubules, intermediate filaments (IFs) constitute the third fibrous component of the cytoskeleton. Functionally, IFs play a role in maintaining mechanical integrity of cells. It is believed that their phosphorylation state is essential for correct assembly and network maintenance. Alterations of IF assembly are pathological features of several diseases (e.g. epidermolysis bullosa simplex, amyotrophic lateral sclerosis).. Compared to the 65 genes coding for human IFs, the cytoplasmic IF cytoskeleton in C. elegans consists of only 16 differentially expressed polypeptides, several of which fulfil essential functions. C. elegans IFs are expressed mainly in epithelial organs. They occur as three dimensional networks in the uterus, as polarized networks in the terminal web of intestinal cells or as dense bundles in the marginal cells of the pharynx. To examine molecular mechanisms that are responsible for these different assembly types we designed an optical screen. To this end we established transgenic strains with distinct and easily discernible fluorescence patterns. They are being subjected to a genome wide RNAi screen to identify gene products altering these patterns. We will further assess the consequence of altered IF organization on cell functions in the nematode.