title: Defects in the first wave of folliculogenesis in mouse XO ovaries.
abstract: In mouse ovaries, the first wave of folliculogenesis perinatally starts near the medullary region, which directs the initial round of follicular growth soon after birth. At the same time, cortical primordial follicles start forming in the ovarian surface region, and then some are cyclically recruited for the second and subsequent rounds of follicular growth. Recent studies suggest different dynamics between the first and subsequent waves of follicular growth in postnatal ovaries. However, the phenotypic differences between these phases remain unclear. Here, we show direct evidence that XO female mice, a murine model for Turner Syndrome, lack the first wave of folliculogenesis. Our histopathological analyses of XX and XO littermates revealed a lack of anti-Müllerian hormone (AMH)-positive primary follicles in the XO ovaries by 4 days post partum (dpp). This loss of first follicles was also confirmed by histological bioassay for SRY-dependent SOX9 inducibility, a specific marker for the first follicular granulosa cells. In contrast, cortical primordial follicles formed properly in XO ovaries, and some of them formed primary and secondary follicles in the subcortical region by 7 dpp. They rapidly developed into late antral follicles, showing similarities to XX littermate ovaries by 21 dpp. These results suggest distinct X-monosomy effects between the first and subsequent waves of follicular growth, highlighting the high susceptibility to elimination of XO oocytes in the first wave of mammalian folliculogenesis.
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Kento
authors.initials: K
authors.lastname: Miura
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Chiharu
authors.initials: C
authors.lastname: Murata
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Harikae
authors.affiliation: Department of Experimental Animal Model for Human Disease, Center for Experimental Animals, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.
authors.forename: Hitomi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Experimental Animal Model for Human Disease, Center for Experimental Animals, Tokyo Medical and Dental University, Tokyo 113-8510, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Kanai-Azuma
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Kurohmaru
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Tsunekawa
authors.affiliation: Department of Veterinary Anatomy, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Yoshiakira
authors.initials: Y
authors.lastname: Kanai
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D000074842:Forkhead Box Protein L2 / Q000378:metabolism; D008810:Mice, Inbred C57BL; D008813:Mice, Inbred ICR; D008822:Mice, Transgenic; D010053:Ovary / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D055758:SOX9 Transcription Factor / Q000378:metabolism; D014424:Turner Syndrome / Q000473:pathology / Q000503:physiopathology*
chemical_list: D000074842:Forkhead Box Protein L2; C498893:Foxl2 protein, mouse; D055758:SOX9 Transcription Factor; C527933:Sox9 protein, mouse
keywords: Anti-Müllerian hormone (AMH); Folliculogenesis; Granulosa cell; Oocyte; XO mice