Expression of ftz-f1^dsRNA.hs.cCa driven by Scer\GAL4^Cg.PA (along with TubGAL80ts, to allow expression only after puparium formation) significantly delays timing and efficiency of pupation compared to controls; no significant changes are seen when expression is driven by Scer\GAL4^elav.PLu, Scer\GAL4^how-24B, Scer\GAL4^Mef2.PR, Scer\GAL4^C855a or Scer\GAL4^repo.

Heatshock induced expression of ftz-f1^dsRNA.hs.cCa about 18 and 12 hours before puparium formation results in normal puparium formation, although 37% of these animals fail to evert usually one spiracle. The majority of these animals fail to progress through the early stages of metamorphosis and die as prepupae. Heatshock induced expression of ftz-f1^dsRNA.hs.cCa about 0 and 6 hours after puparium formation also leads to animals arresting development at the prepupal stage. Although these animals display normal gas bubble formation, they fail to translocate the bubble to the anterior end, and die after several days with a prominent bubble in the middle of the body. In addition eversion of the adult head is completely blocked and the larval mouthhooks that are normally expelled at head eversion remained attached at the anterior end of the animal.