Talk:Genital - Female Development
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Cite this page: Hill, M.A. (2019, August 20) Embryology Genital - Female Development. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Talk:Genital_-_Female_Development
Identification of the genes regulated by Wnt-4, a critical signal for commitment of the ovary
Exp Cell Res. 2015 Mar 15;332(2):163-78. doi: 10.1016/j.yexcr.2015.01.010. Epub 2015 Jan 30.
Naillat F1, Yan W2, Karjalainen R3, Liakhovitskaia A4, Samoylenko A1, Xu Q1, Sun Z2, Shen B2, Medvinsky A4, Quaggin S5, Vainio SJ6.
The indifferent mammalian embryonic gonad generates an ovary or testis, but the factors involved are still poorly known. The Wnt-4 signal represents one critical female determinant, since its absence leads to partial female-to-male sex reversal in mouse, but its signalling is as well implicated in the testis development. We used the Wnt-4 deficient mouse as a model to identify candidate gonadogenesis genes, and found that the Notum, Phlda2, Runx-1 and Msx1 genes are typical of the wild-type ovary and the Osr2, Dach2, Pitx2 and Tacr3 genes of the testis. Strikingly, the expression of these latter genes becomes reversed in the Wnt-4 knock-out ovary, suggesting a role in ovarian development. We identified the transcription factor Runx-1 as a Wnt-4 signalling target gene, since it is expressed in the ovary and is reduced upon Wnt-4 knock-out. Consistent with this, introduction of the Wnt-4 signal into early ovary cells ex vivo induces Runx-1 expression, while conversely Wnt-4 expression is down-regulated in the absence of Runx-1. We conclude that the Runx-1 gene can be a Wnt-4 signalling target, and that Runx-1 and Wnt-4 are mutually interdependent in their expression. The changes in gene expression due to the absence of Wnt-4 in gonads reflect the sexually dimorphic role of this signal and its complex gene network in mammalian gonad development. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved. KEYWORDS: Female development; Germ line; Organogenesis; Ovary; Runx-1; Sex determination; Somatic cells; Testis; Wnt-4
Combined laparoscopy and hysteroscopy for the detection of female genital system anomalies results of 3,811 infertile women
J Reprod Med. 2014 Nov-Dec;59(11-12):542-6.
Siam S1, Soliman BS.
OBJECTIVE: To assess the prevalence of Mullerian and gonadal anomalies in a group of infertile women using a combination of diagnostic laparoscopy and hysteroscopy. STUDY DESIGN: This was a retrospective descriptive study in the setting of a university hospital. The records of 3,811 women who underwent laparoscopy and hysteroscopy for infertility were reviewed. RESULTS: Mullerian duct anomalies (MDAs) were diagnosed in 287/3,811 (7.5%) women, gonadal anomalies in 40/3,811 (1.04%) women, MDAs and gonadal anomalies in 22/3,811 (0.57%) women, and "undefined anomalies" in 8/3,811 (0.2%) women. Among the 287 women with MDAs 54.9% were diagnosed with a septate uterus, 14.2% with an arcuate uterus, 10.2% with a bicornuate uterus, 5.8% with a unicornuate uterus, 4.7% with tubal anomalies, 3.6% with a hypoplastic uterus, 2.9% with Mullerian agenesis, 1.8% with a septate uterus and a double cervix, 1.1% with uterus didelphys, and 0.7% with a longitudinal vaginal septum. Among the 40 women with gonadal anomalies 70% were diagnosed with hypoplastic ovaries, 25% with streak gonads, and 5% with an accessory ovary. Among the 22 women with combined Mullerian and gonadal anomalies 50% were diagnosed with streak gonads and a hypoplastic uterus, 31.8% with a hypoplastic uterus and hypoplastic ovaries, and 18.2% with ovarian and tubal anomalies. CONCLUSION: Combined laparoscopy and hysteroscopy are valuable tools for the diagnosis and classification of female genital system anomalies. PMID 25552125
FOXL2 is a female sex-determining gene in the goat
Curr Biol. 2014 Feb 17;24(4):404-8. doi: 10.1016/j.cub.2013.12.039. Epub 2014 Jan 30.
Boulanger L1, Pannetier M1, Gall L1, Allais-Bonnet A1, Elzaiat M1, Le Bourhis D2, Daniel N1, Richard C1, Cotinot C1, Ghyselinck NB3, Pailhoux E4.
The origin of sex reversal in XX goats homozygous for the polled intersex syndrome (PIS) mutation was unclear because of the complexity of the mutation that affects the transcription of both FOXL2 and several long noncoding RNAs (lncRNAs). Accumulating evidence suggested that FOXL2 could be the sole gene of the PIS locus responsible for XX sex reversal, the lncRNAs being involved in transcriptional regulation of FOXL2. In this study, using zinc-finger nuclease-directed mutagenesis, we generated several fetuses, of which one XX individual bears biallelic mutations of FOXL2. Our analysis demonstrates that FOXL2 loss of function dissociated from loss of lncRNA expression is sufficient to cause an XX female-to-male sex reversal in the goat model and, as in the mouse model, an agenesis of eyelids. Both developmental defects were reproduced in two newborn animals cloned from the XX FOXL2(-/-) fibroblasts. These results therefore identify FOXL2 as a bona fide female sex-determining gene in the goat. They also highlight a stage-dependent role of FOXL2 in the ovary, different between goats and mice, being important for fetal development in the former but for postnatal maintenance in the latter. Copyright © 2014 Elsevier Ltd. All rights reserved.
Development of the human Müllerian duct in the sexually undifferentiated stage
Anat Rec A Discov Mol Cell Evol Biol. 2003 Jun;272(2):514-9.
An embryological explanation for the development of the Müllerian duct still poses a major challenge. The development of this duct was investigated systematically in human embryos. Seven embryos (Carnegie stages 18-23) were serially sectioned in the frontal, sagittal, and transversal planes at a thickness of 10 microm and stained with hematoxylin and eosin (H&E) for histological analysis. In all observed embryos, the caudal end of the Müllerian duct was found to be intimately connected to the Wolffian duct. The opening of the Müllerian duct to the coelomic cavity was formed as the result of an invagination of the coelomic epithelium at Carnegie stage 18. The duct grew independently from the invagination during stages 19-23. The fused duct (uterovaginal canal) bifurcated at the caudal portion at Carnegie stages 22 and 23. This is the first description of the caudal portion of the fused Müllerian ducts separating again and returning to each of the Wolffian ducts in human embryos. Copyright 2003 Wiley-Liss, Inc.
Female development in mammals is regulated by Wnt-4 signalling
Nature. 1999 Feb 4;397(6718):405-9.
Vainio S1, Heikkilä M, Kispert A, Chin N, McMahon AP.
In the mammalian embryo, both sexes are initially morphologically indistinguishable: specific hormones are required for sex-specific development. Mullerian inhibiting substance and testosterone secreted by the differentiating embryonic testes result in the loss of female (Mullerian) or promotion of male (Wolffian) reproductive duct development, respectively. The signalling molecule Wnt-4 is crucial for female sexual development. At birth, sexual development in males with a mutation in Wnt-4 appears to be normal; however, Wnt-4-mutant females are masculinized-the Mullerian duct is absent while the Wolffian duct continues to develop. Wnt-4 is initially required in both sexes for formation of the Mullerian duct, then Wnt-4 in the developing ovary appears to suppress the development of Leydig cells; consequently, Wnt-4-mutant females ectopically activate testosterone biosynthesis. Wnt-4 may also be required for maintenance of the female germ line. Thus, the establishment of sexual dimorphism is under the control of both local and systemic signals.