Fig. 3

Fig. 3 Mutant bum^-/- lenses display significantly increased levels of apoptotic cell death in the anterior lens region at 4 dpf. (A, B) External views of the heads (A, B) and eyes (A′, B′) of 4 dpf sibling (wild-type, wt; A, A′) and bum^-/- larvae (B, B′) showing Acridine Orange fluorescence to reveal cells undergoing apoptosis . The outer margins of the eyes (outer dotted lines in A and B) and the inner margins of the pupils (inner dotted lines in A and B; dotted lines in A′ and B′) are indicated. Note the reduced and irregular pupil diameter in the bum^-/- mutant larvae. While the wild-type lenses do not show Acridine Orange-positive cells (A′), mutant lenses regularly contain numerous fluorescent cells (B). (C) Statistical analysis of the number of apoptotic cells in 4 dpf sibling (left) and bum^-/- mutant larvae (right) showing highly significant numbers of apoptotic cells in the mutant lenses (but not in the wild-type), which suggests a mechanism for the regression of the lens tumours in bum^-/-. Error bars represent the standard error of the mean (SEM).