slimb mutant cells accumulate E2F in S phase. (A-C) slmb8, hs-slmb disc cells without heat shock, (D-F) slmb8, hs-slmb disc cells 1.5 hour after a heat shock restoring Slimb expression. E2F is in red, BrdU in green. C and F show merged images of A and B and D and E respectively. Asterisks point to cells with high BrdU incorporation that still express E2F. Scale bar is 5 μm.