Figure 2

MAPK activation is conserved in parthenogenetic nematodes. Gonad preparations of parthenogenetic (P), hermaphroditic (H) and bisexual (B) nematode species stained for active MAP kinase (left panel; corresponding DIC picture: right panel). In all five nematode species with three different modes of reproduction, MAP kinase activation can be detected in proximal oocytes as described for the C. elegans system [28]. It is therefore independent of the reproductive strategy. In C. elegans, MAP kinase activation is biphasic and can also be observed in the meiotic zone (mz) of the syncytial gonad (panel A, bracket; [28, 47]). The pronounced nuclear staining in Acrobeloides species might reflect early MAP kinase dependent gene expression. sp: sperm. st: spermatheca. int: intestine. emb: embryo. -1, -2, -3: proximal oocytes, -1 is most proximal. All gonads are oriented with proximal to the left. Bar: 20 μm.