The expression of fzr^UAS.cTa only before the binucleation stage (i.e. expression under the combined control of Scer\GAL4^NP5399 and Gal80[ts], and shift from the permissive 19[o]C temperature to the restrictive 29[o]C temperature only during 30h-60h after puparium formation) leads to significantly smaller male accessory gland lobes in the expanded state, as well as significantly lower mating-induced shrinkage rate and efficiency, as compared to control. These male accessory gland lobes also exhibit significantly fewer cells and significantly lower overall ploidy than controls; moreover, whereas control male accessory gland cells are typically binucleate octoploid cells (4N x 2), fzr^UAS.cTa-expressing glands show a high proportion of tetraploid or octoploid single-nucleated cells (4N x 1 or 8Nx1). This seem to correlate with reduced ejection of seminal fluid, as there is a significant decrease in accessory gland proteins (i.e. Sp-GFP) being transferred during mating, as compared to controls. Males expressing fzr^UAS.cTa induce lower egg laying in mated females 10-14 after mating, but not before or after that period.