In the embryo comma stage,
daf-21 mRNA was strongly detected in cells of the head region and less so in other areas. In the hatched L1 larvae,
daf-21 mRNA was mainly distributed in the germline precursor cells Z2 and Z3 and the head region, whereas in the adult hermaphrodite, it was localized uniquely in the germ cells. In the distal arms of the adult hermaphrodite, mitotically dividing germline cells were strongly stained with the antisense probe, but not with the sense probe. As the oocytes matured, the signal strength of the antisense probe seemed to decrease.