Fig. 6. Cell cycle arrest and non-autonomous proliferation in Uba1 mosaics. (A,B) Third instar mosaic Uba1^D6 (A) and Uba1^H42 (B) wing discs incubated at 29°C. Note lack of BrdU labeling in Uba1^D6 mutant clones, and increased BrdU labeling in wild-type tissue surrounding Uba1^D6 clones. Proliferation in Uba1^H42 mosaics is homogenous within and outside the clones (B). (C,D) Cyclin A labeling of eye discs from third instar larval eye discs containing Uba1^D6 (C) and Uba1^H42 (D) mutant clones. Cyclin A levels are increased in Uba1^D6 clones spanning the morphogenetic furrow (arrows in C). Clones of the weak allele Uba1^H42 contain slightly increased Cyclin A levels (D, arrows). However, this increase does not affect cell proliferation (B).