Fig. 1.

Mutants synthetic sterile with puf-8(-) belong to three distinct classes. Dissected gonads, stained with the DNA-binding dye DAPI, are shown. Only the germline nuclei are visible. In this and subsequent figures, the distal mitotic region is oriented towards the left and the proximal region containing gametes to the right. Regions of the germline with germ cells at different stages of development are marked with solid white lines and labelled in the wild-type image. Class I mutants have very few germ cells. Class II mutants have tumourous germlines. This class has two subclasses. In one, the distal mitotic region is followed by a region with sperm, which is then followed by mitotically proliferating germ cells. In the second subclass, only mitotic germ cells were observed. Class III mutants fail to switch from spermatogenesis to oogenesis and make more sperm than do wild type.