ONO Masafumi
   Department   School of Medicine(Tokyo Women's Medical University Adachi Medical Center), School of Medicine
Article types Original article
Language English
Peer review Peer reviewed
Title Aromatase-null mice expressing enhanced green fluorescent protein in germ cells provide a model system to assess estrogen-dependent ovulatory responses.
Journal Formal name:Transgenic research
Abbreviation:Transgenic Res
ISSN code:15739368/09628819
Domestic / ForeginForegin
Volume, Issue, Page 23(2),pp.293-302
Author and coauthor Toda Katsumi, Hayashi Yoshihiro, Yamashita Atsuko, Okabe Masaru, Ono Masafumi, Saibara Toshiji
Publication date 2014/04
Summary Enhanced green fluorescent protein (EGFP) has provided us with valuable approaches for tracking living cells. We established a novel line of transgenic mice, which express EGFP in the testis and ovary. Histological analysis demonstrated that spermatids in the testis and oocytes in ovarian follicles beyond preantral stages were positive for EGFP. By exploiting these features, we evaluated ovulatory responses of aromatase-gene (Cyp19a) knockout mouse expressing the EGFP transgene, which is totally anovulatory due to 17β-estradiol (E2) deficiency. Ovulation in the knockout mice was induced by sequential injections of E2 on days 1, 4 and 5, pregnant mare serum gonadotropin on day 4 and human chorionic gonadotropin on day 6. Fluorescent oocytes were readily detectable at 15 h after the last gonadotropin injection in the oviduct under a fluorescence stereomicroscope, even when only one oocyte was present. However, when E2 supplementation on day 4 or day 5 in the regimen was omitted, no ovulated oocytes were detected, indicating that exogenous E2 supplementation at the time of gonadotropin stimulation is necessary to induce ovulation in aromatase-gene knockout mice. Our results further demonstrated that the current mouse line can provide an alternative tool to study germ cell biology, including oogenesis, ovulation and senescence.
DOI 10.1007/s11248-013-9771-y
PMID 24272335