Abstract
At the onset of metamorphosis in D.melanogaster, a large pulse of ecdysone causes puparium formation and this is followed by another small ecdysone pulse that induces pupation. The pupation occurs 12 hours after puparium formation at standard conditions suggesting that the fly is endowed with a biological timer to measure the time for pupation. To investigate the molecular mechanism of this timer system, stabilized Blimp-1 was expressed from the hs-Blimp-1 transgene and pupation timing was analyzed. Results showed that pupation timing was delayed depending on the stability and timing of Blimp-1 expression. Moreover, differences in pupation timing were observed depending on dose of endogenous gene or transgene. These results indicate that expression level, timing and stability of Blimp-1 are important to determine pupation timing.