Furthermore, we observed that knockout mutations in both genes, either alone or together, have little effect on sperm function. Phylogenetic analysis indicates that the duplication event that produced the paralogs occurred prior to the radiation of the Caenorhabditis species included in the analysis, allowing a long period for the paralogs to diverge in function. Here, we investigate a paralog to spe-47: spe-50, which has a highly conserved sequence and expression, but which is not functionally redundant to spe-47.

elegans spermatids to crawling spermatozoa is affected by a number of genes including spe-47.