"Drosophila" genetics as a tool in the search for novel components of the S6 kinase signaling pathway

Signaling events that converge on the activation of the TOR/S6K pathway have
been shown to be critically related to growth. Recent investigations on the molecular
network controlling growth have revealed that Drosophila melanogaster constitutes an
efficient alternative model to the mammalian system. As the nature of interactions
between known components of the pathway is becoming more understood, it is clear
that a number of elements are lacking. Recently the Thomas laboratory initiated an EP
screen in Drosophila utilizing a unique phenotype in the wing, where the yeast Gal-4
promoter was used to drive expression of random genes in the dorsal wing
compartment of the flies. An enhancement of growth in this tissue could then be
observed by curvature of the wing. When UAS dS6K is driven with apterous- GAL4
in Drosophila, a bent-down wing phenotype is observed. By screening of random EP
insertions combined with UAS dS6K, a number of enhancers were discovered, two of
which are presented in this thesis. We show that both orb2 and IP3K1 are genes which
have a role in the control of growth, and provide models which can help to explain
their role in S6K/TOR signaling.