CPEB3 mRNA during postnatal development. The relative fold change in the amount of CPEB3 mRNA was shown with the aid of real-time PCR. Seven postnatal ages flanking the eye-opening event were used for this study. For each sample, the level of CPEB3 mRNA was normalized to that of 18S RNA in the exact same sample. All experiments were repeated three times. All ages were calibrated relative to the postnatal age P1 and expressed as fold changes. Statistically significant differences were found by ANOVA between sets of two bracketed ages as indicated (p <= 0.05). For each age, the number of samples n >= 6. Error bars represented standard error of the mean (SEM). The asterisk indicated the approximate time of eye-opening. The results demonstrated that CPEB3 was significantly up-regulated in the retina from P1 to P12 (before eye-opening), and from P16 to P30 (after eye opening), and reached maximum in the adulthood (P60).