Fig. 5. sina is required for phyl-mediated Ac downregulation. (A-D) Anti-Ac staining is shown in red. (A-C) Ac protein levels at the AWM of the third-instar wing disks. The dorsal and ventral Ac clusters are indicated by d and v, respectively. (A,A') ap-Gal4>UAS-GFP wing disk. Ac levels in the dorsal GFP-expressing clusters are comparable to that in the ventral clusters. GFP expression is shown in blue. (B,B') ap-Gal4>UAS-flag-phyl wing disk. Ac levels in the dorsal clusters are strongly reduced by misexpression of Flag-tagged Phyl (blue). (C,C') sina²/sina³ wing disk expressing Flag-Phyl in the dorsal clusters. Misexpression of Flag-Phyl fails to downregulate Ac protein levels in sina²/sina³ mutants. (D-D'') In the sina³ mutant clone (GFP negative), Ac accumulates in the SOPs (D') and these SOPs remained as single cells at 16-18 hours APF (D'').