Analysis of the fit-1 gene encoding a ECM protein, flectin, in Caenorhabditis elegans.

Flectin is a new type of extracellular matrix protein and its function was suggested to provide a microenvironment of great elasticity. The C. elegans genome database revealed the presence of a flectin homologue, fit-1, which shows approximately 40% similarity (20% identity) to chick flectin. Here we propose a new gene structure for the fit-1 based on our experiments and the partial cDNA clones obtained from Y. Kohara and further suggest that the previous gene prediction is incorrect. FLT-1 is shown to be expressed in various neurons, hypodermal cells, distal tip cells and vulva epithelial cells. Immunostaining results with anti-FLT-1 antibody, further confirm the FLT-1 expression in vulva epithelial cells. The lipophilic dye, DiI, was used to identify the head neurons expressing GFP and results indicated that none of the head neurons expressing GFP are the 6 chemosensory neurons. In order to determine the function of flt-1 gene, RNA-mediated interference (RNAi) experiments were conducted.