Tergite phenotype caused by ubiquitous expression of CAG or CUG repeat RNA in <i>Drosophila</i>.

<p><b>A</b>, wild-type flies show a regular arrangement of tergite bands along the dorsal abdomen (arrows). <b>B</b>, An example of the disrupted phenotype, whereby tergites do not fuse at all (white arrowheads), or fuse only partially (grey arrowheads). <b>C</b>, Phenotype severity was scored on a scale of 1–4, images show typical examples from each category, where category 1 is like wildtype; category 2, tergites disrupted but not split; category 3, one tergite split; and category 4, two or more tergites split. <b>D-E</b>, Graphs showing the proportion of progeny within each scoring category. <b>D</b>, <i>da-GAL4</i> driven expression of the EV control line (n = 161) and, <b>E</b>, <i>da-GAL4</i> driven expression of <i>4xrCAA_∼100</i> [line 1] (n = 148) gives no phenotype with almost all progeny like wild-type. <b>F</b>, <i>da-GAL4</i> driven expression of <i>4xrCUG_∼100 [line 1]</i> (n = 271) or <b>G</b>, <i>4xrCAG_∼100 [line 2]</i> (n = 343) gives a tergite disruption phenotype. <b>H,</b> Schematic (not to scale) showing the location of histoblast cells (black). Histoblasts proliferate and migrate to form the tergite bands (arrows). <b>I</b>, Expression within the histoblasts using <i>T155-GAL4</i> gives wild-type tergites in EV control progeny (n = 56). <b>J</b>, <i>T155-GAL4</i> expression of <i>4xrCAG_∼100</i> [line 1] (n = 25) gives a mild tergite phenotype, ***p<0.001 comparing the proportion with a phenotype in <b>I</b> and <b>J</b>.