An antiserum against quail 7 day gonadal germ cells was found to react specifically with gonadal germ cells of both sexes. Transverse sections from a range of early quail developmental stages were submitted to the antibody PAP reaction. Blastodiscs from the earliest uterine stages (II to X E.G. & K) reacted very strongly, while the overall reaction gradually decreased in older blastoderms. At stage XIII both epiblast and hypoblast were weakly stained, but some large, PGC-like cells stained intensively. During gastrulation (PS formation) the reaction of the epiblast disappears quicker than that of the hypoblast. The newly formed mesoderm and entoderm do not react at all and the reaction gradually becomes limited mainly to the PGCs and somewhat to the primary hypoblast which is moving into the germinal crescent. The widely spread reaction at the early stages is thus gradually being restricted to the PGCs.
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Front Endocrinol (Lausanne)
January 2025
Sichuan Provincial Key Laboratory of Traditional Chinese Medicine Regulation of Metabolic Diseases, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China.
Sertoli cells (SCs), as the somatic cells in the testis of male mammals, play a crucial role in the close association with germ cells. The blood-testicular barrier (BTB), established by their tight junctions, provides immune protection to germ cells, leading to their characterization as "sentinel" cells. Moreover, the physiological process of testicular development and spermatogenesis in male animals is intricately tied to the secretory activities of SCs.
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CNRS, INRAE, Université de Tours, PRC, Nouzilly, France.
Female infertility, which affects 10-20% of couples worldwide, is a growing health concern in developing countries. It can be caused by multiple factors, including reproductive disorders, hormonal dysfunctions, congenital malformations and infections. In vitro and in vivo studies have shown that plant extracts regulate gonadotropin-releasing hormone, kisspeptin, and gonadotropin expression and/or secretion at the hypothalamic-pituitary level and modulate somatic and germ cells, such as steroidogenesis, proliferation, apoptosis, and oxidative stress at the ovarian level.
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Université de Strasbourg, IGBMC UMR 7104, Illkirch, France; CNRS, UMR 7104, Illkirch, France; Inserm, UMR-S 1258, Illkirch, France; IGBMC, Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France. Electronic address:
In mammals, differentiation of germ cells is crucial for sexual reproduction, involving complex signaling pathways and environmental cues defined by the somatic cells of the gonads. This review examines the long-standing model positing that all-trans retinoic acid (ATRA) acts as a meiosis-inducing substance (MIS) in the fetal ovary by inducing expression of STRA8 in female germ cells, while CYP26B1 serves as a meiosis-preventing substance (MPS) in the fetal testis by degrading ATRA and preventing STRA8 expression in the male germ cells until postnatal development. Recent genetic studies in the mouse challenge this paradigm, revealing that meiosis initiation in female germ cells can occur independently of ATRA signaling, with key roles played by other intrinsic factors like DAZL and DMRT1, and extrinsic signals such as BMPs and vitamin C.
View Article and Find Full Text PDFCurr Top Dev Biol
January 2025
School of Molecular Biosciences, Washington State University, Pullman, Washington, United States. Electronic address:
For mammalian spermatogenesis to proceed normally, it is essential that the population of testicular progenitor cells, A undifferentiated spermatogonia (A), undergoes differentiation during the A to A1 transition that occurs at the onset of spermatogenesis. The commitment of the A population to differentiation and leaving a quiescent, stem-like state gives rise to all the spermatozoa produced across the lifespan of an individual, and ultimately determines male fertility. The action of all-trans retinoic acid (atRA) on the A population is the determining factor that induces this change.
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January 2025
CiRA Foundation, Research and Development Center, Osaka, Japan.
Mouse embryonic fibroblasts (MEFs) have been widely used as feeder cells in embryonic stem cell cultures because they can mimic the embryonic microenvironment. Milk fat globule-epidermal growth factor 8 (MFGE8) is expressed during mouse gonadal development, 10.5-13.
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