(A) ELAV marks the differentiating neuronal tissue posterior to the MF in control discs.
(B) In ey-FLP-induced cos2 mosaics, ELAV expression does extend anterior to the MF. This precocious expansion is associated with mutant clones, but is also seen in adjacent cos2+ tissue (shown in inset outlined in dashed line). ELAV-labeling is not grossly altered in cos2 clones posterior to the MF.
(C) dpp-lacZ marks the MF in wild-type eye discs.
(D) In ey-FLP-induced cos2 mosaics, multiple changes in dpp-lacZ expression are observed. The MF is shifted anterior around clones crossing the MF (arrow in D’). These clones reduce expression of dpp-lacZ (arrowhead). In contrast, clones further anterior and not associated with the MF autonomously induce dpp-lacZ expression (asterisk). β-GAL staining posterior to the MF is due to a weak GMR-lacZ reporter on the ey-FLP chromosome.
Genotypes:
(A)
y w ey-FLP; FRT42 ubi-GFP/CyO
(B)
y w ey-FLP; FRT42 cos2H29 /FRT42 ubi-GFP
(C)
y w ey-FLP; ubi-GFP FRT40/CyO; dpp-lacZ
(D)
y w ey-FLP GMR-lacZ; FRT42 cos2H29 /FRT42 ubi-GFP; dpp-lacZ