Germ line gene regulation by chromatin remodelling during meiosis in Caenorhabditis elegant

Chromatin proteins together with transcription factors, establish the appropriate gene transcription profile necessary for proper eukaryotic development. One of these factors, the chromatin remodeler Mi2, plays a crucial role in stem cell proliferation, differentiation and cell fate maintenance processes. Using Caenorhabditis elegans, which constitutes a remarkable model for studying chromatin factors, we showed that Mi2 ortholog LET-418, is essential in the embryonic to post-embryonic development transition. Thereby, it is involved in the regulation of the proliferation and differentiation of the germ and blast cells. In addition, we show that it is required to repress the germ line transcription program in the somatic cells of the developing embryo. In order to identify possible interactions of LET-418 with other factors in the regulation of the pot-embryonic development and in the repression of the germline expression program, two wide genome RNAi screens for suppressors of defects associated with lack of LET-418 activity were performed by our group. Thirty-two genes were found to antagonized LET-418 functions and most of them are members of chromatin remodelling complexes. Among the other LET-418 suppressors, we identified an interesting Zinc-finger transcription factor with an unknown function, the LSL-1 protein. Our project aims to determine how these two factors are capable of shaping the chromatin structure of meiotic prophase chromosomes to ensure viable gamete production.