C. elegans spermatogenesis has proven to be a useful model for studying the more general developmental processes of cellular differentiation and cell-cell interactions. Mutants in the
spe-16 gene show sperm-based sterility and pleiotropic defects in spermatogenesis, including abnormal meiotic spindle positioning and orientation, defects in nuclear and chromosomal segregation and inappropriate cytoplasmic polarization and organelle maturation. These defects may be more severe in hermaphrodite-derived sperm than in male-derived sperm.
spe-16 lies on LGIIIR, between the cloned genes
tra-1 and
dpy-18 (Hill, Harfe, Dobbins and LHernault, Genetics, in press). We have used polymorphism mapping to narrow the physical interval that must contain the
spe-16(
hc54ts) mutation. To date,
spe-16(
hc54ts) has been mapped to a ~ 27 kb region containing two primary candidate genes, an oxysterol binding protein and a ribosomal protein
s6 kinase. Mapping continues with three additional polymorphisms located within the 27 kb interval, and will be followed by sequencing to identify the
spe-16(
hc54ts) mutation.