Fig. 5

Cnn2-KO mice show complete depletion of growing follicles at 16 months of age. A Representative histological image of a 16 months old WT mouse ovary showed notable ovarian follicles (arrows: ovarian follicles, arrowhead: corpus luteum) whereas 16 months old Cnn2-KO mouse ovary showed complete loss of the growing follicle (B). It is interesting that the ovary of 16 months old Cnn2-KO mouse shows many remnants of the corpus luteum but without any observable growing follicle. While the present study focuses on the depletion of ovarian follicles, the effect of Cnn2-KO on generating the corpus luteum is worth investigating in future studies