We have established an in vitro culture system for adult
schistosomes that allows monitoring gene expression for up to
more than ten days. Comparing female worms that are paired
with those that have been separated, we find distinct
differences, clearly documenting an influence of the male in
female gene expression. In perfect coincidence with classical
observations that were based on histological techniques, we
find that the male particularly regulates gene expression in
those tissues that are characterized by cell proliferation,
e.g. the vitellaria. From these results, we hypothesize that
the key target for the inductive signal that is transferred
from the male to the female during pairing is the activation
of a growth factor that stimulates mitotic proliferation.
