Article

Building Pathways for Ovary Organogenesis in the Mouse Embryo

Department of Veterinary Biosciences, University of Illinois at Urbana-Champaign, Illinois, USA.
Current Topics in Developmental Biology (Impact Factor: 4.21). 01/2010; 90:263-90. DOI: 10.1016/S0070-2153(10)90007-0
Source: PubMed

ABSTRACT Despite its significant role in oocyte generation and hormone production in adulthood, the ovary, with regard to its formation, has received little attention compared to its male counterpart, the testis. With the exception of germ cells, which undergo a female-specific pattern of meiosis, morphological changes in the fetal ovary are subtle. Over the past 40 years, a number of hypotheses have been proposed for the organogenesis of the mammalian ovary. It was not until the turn of the millennium, thanks to the advancement of genetic and genomic approaches, that pathways for ovary organogenesis that consist of positive and negative regulators have started to emerge. Through the action of secreted factors (R-spondin1, WNT4, and follistatin) and transcription regulators (beta-catenin and FOXL2), the developmental fate of the somatic cells is directed toward ovarian, while testicular components are suppressed. In this chapter, we review the history of studying ovary organogenesis in mammals and present the most recent discoveries using the mouse as the model organism.

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Available from: Humphrey Hung-Chang Yao, Mar 17, 2014
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    • "While there are elegant reviews of germ-line cyst breakdown , primordial follicle formation, the onset of follicle activation, and cellÀcell communication during antral follicle development (e.g., Albertini et al., 2001; Pepling, 2006, 2012; Edson et al., 2009; Su et al., 2009; Trombly et al., 2009a; Binelli and Murphy, 2010; Liu et al., 2010a; Jagarlamudi and Rajkovic, 2012; Sanchez and Smitz, 2012), the remainder of this review will focus on a specific cadre of factors that have the unique properties of being present throughout the duration of germ-line cyst formation to establishment of primordial follicles, in addition to clearly playing a role in survival of early stage follicles. Their known activities support the hypothesis that the foundation of folliculogenesis begins at the onset of ovarian cord formation , coinciding with transition to the oocyte fate, and requires cooperation between both germ cells and somatic cells (Eppig, 1991; Byskov et al., 1997; Lei et al., 2006; Qing et al., 2008; Nicholas et al., 2010). "
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    • "Beginning with the generation of the Wnt4 mutation over 10 years ago (Vainio et al., 1999), canonical Wnt signaling has emerged as the predominant pathway controlling ovarian development (Chassot et al., 2008a; Tevosian and Manuylov, 2008; Liu et al., 2010a). While loss of several sex-determining genes in the XY gonad, including Sry, Sox9, or Fgf9, leads to male-to-female sex reversal, no single gene mutation leads to primary female-to-male sex reversal in the XX gonad (reviewed in Eggers and Sinclair (2012)). "
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    • "Because of their important roles in initiating male or female gonadal development in mammals, the respective implications of either Dmrt1 or Foxl2 transcription factors were examined. Further on, two of the major signaling pathways central for early gonadal induction and maintenance in mammals, namely the canonical Hedgehog and Wnt4/β-catenin signaling pathways (Wilhelm et al. 2007; Liu et al. 2010; Franco and Yao 2012), were investigated. "
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