Tap42 is expressed in imaginal discs and primarily localized in the peripodial epithelium (PE) region.

<p>Panel A: Wing (A1–A3), haltere/3^rd leg (A4–A6), 2^nd leg (A7–A9), and eye imaginal discs (A10–A12) isolated from 3^rd instar larvae were immunostained for Tap42 protein expression (green) and counter-stained with the nucleic acid dye TO-PRO3 (purple). <i>UAS-Tap42^RNAi</i> control flies exhibited abundant expression of <i>Tap42</i> in the PE region of these imaginal discs (A1, A4, A7, & A10). <i>Tap42^RNAi</i> expression with the <i>pnr</i> (A2, A5, A8, & A11) and <i>ap</i> (A3, A6, A9, & A12) drivers dramatically reduced <i>Tap42</i> expression to nearly undetectable levels. Of note, <i>ap-Gal4</i>-mediated silencing of <i>Tap42</i> also disrupted the morphological patterning of the wing disc, as revealed by TO-PRO3 staining (A3). Panel B: The localization of Tap42 in the PE region was confirmed by immunofluorescence histochemistry. Immunostaining of wing discs obtained from wild type flies revealed an overlap of Ubx (red) and Tap42 (green) expression (B1). An amplified view of the merged image highlights strong Tap42 expression around the presumptive medial edge (ME) cells of the PE, which localizes near the boundary of the PE and DP (B2). Some Tap42 expression was visualized in the disc proper (DP) cells. Wing discs were counter-stained with the nucleic acid dye TO-PRO3 (blue). Genotypes: (A1, A4, A7, & A10) <i>UAS-Tap42^RNAi/+</i> as control. (A2, A5, A8, & A11) <i>UAS-Tap42^RNAi/+; pnr-Gal4/+</i>. (A3, A6, A9, & A12) <i>ap-Gal4/UAS-Tap42^RNAi; +/+</i>. (B1 & B2) wild type <i>w¹¹¹⁸</i>.