Fig. 4

Severe reproductive defects observed in the Pramex1/Pramel1 dKO mice. A Testis weight of WT, Pramex1 sKO, Pramel1 sKO, and Pramex1/Pramel1 dKO mice obtained during the time-course study from P7 to P365. B Testis index (= testicular weight (g) / body weight (g) × 100) was documented in WT, Pramex1 sKO, Pramel1 sKO, and Pramex1/Pramel1 dKO mice from P7 to P365 (n = 3 ~ 5). C Sperm count in epididymis of WT, Pramex1 sKO, Pramel1 sKO, and Pramex1/Pramel1 dKO mice at P41 (caput and cauda), P60 (cauda), P120 (cauda) and P365 (cauda) of age (n = 3 ~ 5). The referenced sperm count of the dKO was drawn as red solid line in the figure. The formula for the referenced anticipated value of dKO, which calculate effect of two genes deletion without gene interaction in the additive model, was as follows: (\(\mathrm{reference dKO value}=Pramel1 {\text{sKO}}\times \frac{Pramex1\mathrm{ sKO}}{{\text{WT}}}\)[44,45,46] (n = 3 ~ 5). D Litter size of mating tests of male fecundity. The experimental male mice (P60) were mated with adult WT female. The referenced litter size of the dKO was drawn as red solid line. About 6 ~ 7 male mice were tested and about 30 litters were counted for each group. Significance was assessed among the four groups (WT, Pramex1 sKO, Pramel1 sKO, and Pramex1/Pramel1 dKO mice) for C and D. Data were expressed as mean ± SEM. Values that do not share a common superscript (a–d) were found to differ significantly (P < 0.05)