The Mutation of the Ap3b1 Gene Causes Uterine Hypoplasia in Pearl Mice.

The pearl (pe) mouse mutant has been identified as a model for Hermansky-Pudlak syndrome and bears a mutation in the beta3A subunit of the AP-3 complex, which has a core function in the biogenesis and function of various lysosomal-related organelles. Through large-scale mating, we found that female pearl mice also displayed reduced fertility with a smaller litter size. Abnormal uteri in both 1-month-old and 3-month-old mice were observed as having short and thin uterine horns, indicating abnormal development. Histological studies revealed that the endometrial epithelium and endometrial stoma of the uterus were both thinner than those in the normal controls. We examined some key factors in uterine development, including the Hoxa10, Hoxa11, and Wnt5a genes, and found that they all presented lower mRNA and protein levels. The pearl mouse could serve as a model for uterine hypoplasia, a common problem in female infertility.