Figure 3
From: Integrins are required for cardioblast polarisation in Drosophila
Expression of an αPS3 transgene in the CBs restores apicalisation of Robo. Like the ligand Slit, its receptor Robo is apicalised in wildtype (red, A). In scb2 homozygotes, Robo levels are dramatically reduced (B, unadjusted gain shown in inset), however at increased gain, Robo at the midline (arrow) and between ipsilateral cells (arrowhead) is detected. In scb/scb; dMEF-GAL4/UAS-scb embryos, expression of αPS3 only in somatic mesoderm is sufficient to restore apical restriction of Robo (C). Rescue of scb2/scb2 with a cytoplasmically truncated αPS3 transgene yields partial restoration of midline Robo (arrow, D), although Robo between ipsilateral cells is detected (arrowheads). Calibration: 10 microns