Fig. 4. HTH regulates early SER expression both cell autonomously and nonautonomously. All panels are leg discs from ptcGAL4 UAShth UASGFP larvae; SER in red. (A,A’) Ectopic expression of HTH does not affect SER expression in the coxa. (B,B’) Ectopic expression of HTH cell autonomously represses SER expression in the femur (arrow), and cell nonautonomously induces SER (arrowheads). (C) Adult leg displaying bifurcation at the level of the femur (fe). (D-D’’) Ectopic expression of HTH cell autonomously represses DAC expression (white arrow). In the anterior compartment, ectopic HTH results in an induction of DAC expression (black arrow), while in the posterior compartment, ectopic HTH does not affect DAC expression in those cells in which SER was induced (arrowhead).
