The effects of different bacterial food on germline development
Physical and Biological Sciences
Molecular and Cell Developmental Biology, Strome lab
The MES (maternal effect sterile) proteins are chromatin modifiers that are essential for germline development in the model organism Caenorhabditis elegans. When a mes gene is mutated, the homozygous mutants are fertile (generation 1), but 100% of their progeny (generation 2) are sterile and adults have no or very few germ cells. My thesis investigates the influence of food on germline development in mes mutants. In a laboratory setting, C. elegans are typically grown on a specific strain of E. coli, OP50. Mutants for a nuclear hormone receptor are sterile when grown on OP50 but fertile when grown on a different strain of E. coli, HT115, or on OP50 supplemented with tryptophan. I analyzed the effects of HT115 vs. OP50 on germline development in mes mutants. I found that when grown on HT115, some generation 2 mes-2 and mes-3 mutants have significantly increased numbers of germ cells and are sometimes fertile, whereas generation 2 mes-2 mutants grown on OP50 have no or very few germ cells. I also analyzed the effects of HT115 across generations by growing generation 1 and 2 mutants on different food. Additionally, I investigated the differences between mes mutants grown on HT115 and OP50 at a molecular level by staining for histone modifications and X chromosome repression.
