Gonadal Identity in the Absence of pro-Testis Factor SOX9 and pro-Ovary Factor beta-catenin

The main goal of our study is to identify the molecular events that determine the gonadal identity in mammals. Although testis and ovary arise from a common embryonic primordium, they represent outcomes of opposing fate determination. This decision to differentiate into a testis or an ovary hinges upon the balance between two antagonizing factors, pro-testis SOX9 and pro-ovary beta-catenin. This microarray analysis led to the identification of the genes involved in the fate of XX and XY gonads in absence of SOX9 and beta-catenin We developed mouse genetic models that lack either Sox9, beta-catenin, or both specifically in the somatic cells. All embryos used in this study resulted from the crossing between Ctnnb1f/f; Sox9f/f females with Sf1-cre+/Tg ; Ctnnb1+/f; Sox9+/f males. XX and XY fetal gonads were collected at embryonic day E14.5本研究的核心目标为鉴定调控哺乳动物性腺性别决定的分子事件。尽管睾丸与卵巢均起源于同一胚胎原基，但二者实为两种对立命运决定的不同结局。这种向睾丸或卵巢分化的命运抉择，取决于两类拮抗因子之间的动态平衡：促睾丸分化因子SOX9与促卵巢分化因子β-连环蛋白（beta-catenin）。本次芯片（microarray）分析旨在鉴定在SOX9与β-连环蛋白缺失条件下，参与XX和XY性腺命运调控的相关基因。我们构建了在体细胞中特异性缺失Sox9、β-连环蛋白，或同时缺失二者的小鼠遗传模型。本研究使用的全部胚胎，均由基因型为Ctnnb1f/f; Sox9f/f的雌性小鼠与基因型为Sf1-cre+/Tg; Ctnnb1+/f; Sox9+/f的雄性小鼠交配获得。本研究在胚胎发育第14.5天（E14.5）采集了XX和XY型胎儿的性腺组织。