Stat92E sensor activity in <i>ept</i> mutant eye-antennal cells.

<p>Eye discs carrying clones of <i>ept<sup>2</sup></i> mutant cells (A-A″) or <i>FRT80B</i> control cells (B-B″) marked by the absence of GFP (green) and stained for expression of β-galactosidase (β-gal; red in A′ and B′) to detect expression of the <i>3xGAS-lacZ</i> Stat-reporter. Inset in (A-A″) shows an <i>ept<sup>2</sup></i> mutant clone that shows cell autonomous activation of <i>3xGAS-lacZ</i>. Because the <i>3xGAS-lacZ</i> transgene and the <i>ept</i> gene are both located on chromosome arm 3L, the reporter is present in two copies in both <i>FRT80B</i> and <i>ept</i> mutant clones; images in A′ and B′ were captured using exactly the same optical settings. (C–E) Expression of the <i>10xStat>GFP</i> transgene (green) in <i>ept<sup>X1</sup>,H99</i> mosaic discs in which mutant cells are marked by the absence of β-gal (red). Arrowhead marks clone of <i>ept<sup>X1</sup>,H99</i> mutant cells in the eye disc that do not activate <i>10xStat>GFP</i>; arrow marks an example of an antennal clone that activates <i>10xStat>GFP</i> within the clone and in surrounding wild type cells. Images in (E-E″) are of the antennal region of an <i>ept<sup>X1</sup>,H99</i> mosaic disc. White outlines in panel (E″) denotes boundaries of GFP-expressing cells. Expression of the Stat reporter <i>10xStat>GFP</i> (green) in a control <i>FRT80B/M(3)</i> eye disc (F) and an <i>ept<sup>2</sup></i> eye-antennal tumor (G). The disc in (F) was imaged at half the fluorescence intensity relative to the control disc in (G).</p>