Phenotypes resulting from overexpression of Gro variants in the wing disc.

<p>The <i>Ser-Gal4</i> driver was used to drive expression of Gro^WT or Gro internal deletion variants in the wing. (A) A wing containing the driver but no UAS-Gro construct shows no phenotype. Overexpression of Gro^WT (B) and Gro^ΔSP (E) resulted in moderate to severe blistering and vein deformation. Overexpression of Gro^ΔGP (C) resulted in no defects, while overexpression of Gro^ΔCcN (D) resulted in bifurcation of the 4^th and/or 5^th longitudinal vein (LV, arrows). Overexpression of Gro^ΔCR (F) resulted in severe blistering and vein deformation as well as ectopic bristles along the wing vein (inset, yellow arrows). (G) 100 wings of each genotype were scored according to phenotype as indicated showing the differences in the relative severity of the phenotypes generated by overexpression of the various deletion variants. (H) Gro immunoblot of third instar wing discs verifies equal expression levels. Tubulin serves as a control for equal protein levels. (I) In addition to the blistering and wing veination defects, Gro^ΔCcN and Gro^ΔCR Gro overexpression also resulted in 13% and 29% wing scalloping phenotypes (arrows). The severe defects in the Gro^ΔCR overexpressing wings and the milder defects in the Gro^ΔCcN overexpressing wings probably results from a dominant negative function for these variant as discussed in the text. The wing scalloping (J) and the ectopic wing bristles (F and I, indicated by arrows in the high magnification insets), both of which are reminiscent of a Notch pathway hypomorphic phenotypes <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030610#pone.0030610-Hartenstein1" target="_blank">[49]</a>. Except for the high magnification insets in panels F and I, the wing images were obtained using a 4× objective. Scale bars = 400 µm. For the high magnification insets in panels F and I, the images were obtained using a 40× objective.