Many ovarian follicle cells in stage 5-6 egg chambers from dup^{10(A).hsp70.T:Hsap\MYC} adult females subjected to 30 minute heat shocks twice a day have enlarged nuclei. The penetrance of this phenotype is variable. In addition, around 50% of follicle cells in these egg chambers are apoptotic. Third instar eye discs from dup^{10(A).hsp70.T:Hsap\MYC} animals given 3 heat shock pulses over 30 hours have a significantly wider stripe of BrdU incorporating (S-phase) cells just posterior to the morphogenetic furrow than wild-type. This increase in BrDu incorporation does not extend into the differentiating cells further posterior to the furrow. These discs also have a greater number of the asynchronous cycling cells anterior to the furrow and a low level of BrdU incorporating cells within the furrow itself. BrdU incorporation into amplification foci in stage 10B oocyte follicle cells is completely inhibited dup^{10(A).hsp70.T:Hsap\MYC} animals three hours after heat shock.