Fig. 4

SETX prevents GR(50) dipeptide from localizing exclusively to the nucleolus in the fly salivary gland. a We directed expression of GR(50)-GFP or membrane targeted mCD8-GFP, alone or in combination with normal FLAG-SETX(wt), to the salivary gland by crossing transgenic flies with flies expressing the OK6-GAL4 driver. Flies expressing SETX(wt) with mCD8-GFP exhibit localization of SETX throughout the nucleus (TOP), while flies expressing GR(50)-GFP display dense, punctate accumulation of GR(50) dipeptides in the nucleolus (MIDDLE). Co-expression of SETX(wt) and GR(50)-GFP yields localization of GR(50) dipeptides throughout the nucleoplasm, with partial SETX co-localization (BOTTOM). Though representative images are shown here, these identical findings were observed in all 50 cells examined per genotype. Scale bars = 25 µM. b We directed expression of GR(50)-GFP or membrane targeted mCD8-GFP, alone or in combination with normal SETX(wt), to the salivary gland by crossing transgenic flies with flies expressing the OK6-GAL4 driver. As shown here with monochrome imaging, flies expressing FLAG-SETX(wt) with mCD8-GFP exhibit localization of SETX throughout the nucleus (TOP), while flies expressing GR(50)-GFP display accumulation of GR(50) dipeptides in the nucleolus (MIDDLE). Co-expression of SETX(wt) and GR(50)-GFP reduces the accumulation of GR(50) dipeptides in the nucleolus and nucleus (BOTTOM). Scale bars = 50 µM