In adult C. elegans,
klp-18 mRNA expression is strongest in the female germ line. In
glp-4 hermaphrodites, which have a severely under-proliferated germ line, no
klp-18 transcript is detectable. In
fem-2 hermaphrodites, which produce only oocytes,
klp-18 transcript is present at high levels, and in
fem-3 gain-of-function hermaphrodites, which produce only sperm, it is present at approximately wild-type levels. Additional northern blot analysis revealed increasing
klp-18 transcript levels at progressively later stages of wild-type larval development. This increase is likely due to a growing population of germ cells.