F56D2.6 is a putative helicase of the "DEAH box" family that is a homologue of the yeast spliceosomal protein, Prp43p. The Prp43p protein is required for the release of the lariat intron from the spliceosome and also plays a significant role in ribosome biogenesis. RNAi directed toward the F56D2.6 gene in C. elegans shows no overt phenotype, but a balanced strain that produces homozygous F56D2.6 (
ok2951) knockout worms shows a sterile phenotype. DAPI staining of these homozygous mutants reveals that their germlines only have undifferentiated germ cells and no sperm was observed. We are especially interested in potential splicing errors involving the sex determination genes or miRNA required for proper regulation of these sex-determination pathway genes caused by the
ok2951 mutation. To date, we have not found any splicing errors, but using miRNA analysis and qRT-PCR we have found a marked decrease in miR35-41 expression in
ok2951 mutant worms. Potential implications of this data are discussed.