The penis, the organ that bears reproductive and psychological importance, is susceptible to birth defects such as hypospadias or incomplete closure of urethra along the penis shaft. We discover that proper urethral closure in mouse embryos requires a unique mesenchymal cell population originated from outside of the penis. These "extragenital" cells, marked by a lineage marker , migrate from the inguinal region into the embryonic penis and facilitate urethra closure by interacting with adjacent periurethral cells via the epidermal growth factor pathway.
View Article and Find Full Text PDFTesticular fetal Leydig cells are a specialized cell type responsible for embryo masculinization. Fetal Leydig cells produce androgens, that induce the differentiation of male reproductive system and sexual characteristics. Deficiencies in Leydig cell differentiation leads to various disorders of sex development and male reproductive defects such as ambiguous genitalia, hypospadias, cryptorchidism, and infertility.
View Article and Find Full Text PDFIn Brief: Female hypospadias is a little-known and poorly studied birth defect. This research establishes an anatomical and molecular foundation for future research to investigate the origins of this defect.
Abstract: Hypospadias is a congenital anomaly of the external genitalia where the urethra does not properly close.
Reproductive processes are dynamic and involve extensive morphological remodeling and cell-cell interactions. Live imaging of organs enhances our understanding of how biological processes occur in real time. Slice culture is a type of organ culture where thick slices are collected from an organ and cultured for several days.
View Article and Find Full Text PDFHypospadias, or incomplete closure of the urethra along the penis, is the second most common birth defect in the United States. We discovered a population of extra-genital mesenchymal cells that are essential for proper penile urethra closure in mouse embryos. This extra-genital population first appeared in the mesenchyme posterior to the hindlimb of the fetus after the onset of penis formation.
View Article and Find Full Text PDFProgesterone receptor (PGR) plays diverse roles in reproductive tissues and thus coordinates mammalian fertility. In the ovary, rapid acute induction of PGR is the key determinant of ovulation through transcriptional control of a unique set of genes that culminates in follicle rupture. However, the molecular mechanisms for this specialized PGR function in ovulation is poorly understood.
View Article and Find Full Text PDFSertoli cells, first identified in the adult testis by Enrico Sertoli in the mid-nineteenth century, are known for their role in fostering male germ cell differentiation and production of mature sperm. It was not until the late twentieth century with the discovery of the testis-determining gene SRY that Sertoli cells' new function as the master regulator of testis formation and maleness was unveiled. Fetal Sertoli cells facilitate the establishment of seminiferous cords, induce appearance of androgen-producing Leydig cells, and cause regression of the female reproductive tracts.
View Article and Find Full Text PDFGenetic alterations of the gene are associated with a variety of malignancies, including female-related cancers. The role of as either a tumor suppressor gene or an oncogene is tissue-dependent and varies based on the cancer type. Both the amplification and deletion of the gene have been associated with ovarian cancer in humans.
View Article and Find Full Text PDFThe female reproductive tract develops from its embryonic precursor, the Müllerian duct. In close proximity to the Müllerian duct lies the precursor for the male reproductive tract, the Wolffian duct, which is eliminated in the female embryo during sexual differentiation. We discovered that a component of the Wolffian duct, its mesenchyme, is not eliminated after sexual differentiation.
View Article and Find Full Text PDFFront Cell Dev Biol
September 2022
Differentiation of the bipotential gonadal primordium into ovaries and testes is a common process among vertebrate species. While vertebrate ovaries eventually share the same functions of producing oocytes and estrogens, ovarian differentiation relies on different morphogenetic, cellular, and molecular cues depending on species. The aim of this review is to highlight the conserved and divergent features of ovarian differentiation through an evolutionary perspective.
View Article and Find Full Text PDFIn the 1940s, Alfred Jost demonstrated the necessity of testicular secretions, particularly androgens, for male internal and external genitalia differentiation. Since then, our knowledge of androgen impacts on differentiation of the male internal (Wolffian duct) and external genitalia (penis) has been drastically expanded upon. Between these two morphologically and functionally distinct organs, divergent signals facilitate the establishment of tissue-specific identities.
View Article and Find Full Text PDFFate determination and maintenance of fetal testes in most mammals occur cell autonomously as a result of the action of key transcription factors in Sertoli cells. However, the cases of freemartin, where an XX twin develops testis structures under the influence of an XY twin, imply that hormonal factor(s) from the XY embryo contribute to sex reversal of the XX twin. Here we show that in mouse XY embryos, Sertoli cell-derived anti-Mullerian hormone (AMH) and activin B together maintain Sertoli cell identity.
View Article and Find Full Text PDFCompared with the well-described XY sex determination system in mammals, the avian ZW sex determination system is poorly understood. Knockdown and overexpression studies identified doublesex and mab-3-related transcription factor 1 (DMRT1) as the testis-determining gene in chicken. However, the detailed effects of DMRT1 gene disruption from embryonic to adult development are not clear.
View Article and Find Full Text PDFSteroid hormones regulate various aspects of physiology, from reproductive functions to metabolic homeostasis. Steroidogenic factor-1 (NR5A1) plays a central role in the development of steroidogenic tissues and their ability to produce steroid hormones. Inactivation of Nr5a1 in the mouse results in a complete gonadal and adrenal agenesis, absence of gonadotropes in the pituitary and impaired development of ventromedial hypothalamus, which controls glucose and energy metabolism.
View Article and Find Full Text PDFBirth defects of the external genitalia are among the most common in the world. Proper formation of the external genitalia requires a highly orchestrated process that involves special cell populations and sexually dimorphic hormone signaling. It is clear what the end result of the sexually dimorphic development is (a penis in the male versus clitoris in the female); however, the cell populations involved in the process remain poorly defined.
View Article and Find Full Text PDFSexually dimorphic establishment of the reproductive tract system requires sex-specific regression of the Wolffian duct and Müllerian duct in the mesonephros. In an XX embryo, the Wolffian duct regresses under the control of the mesenchymal transcription factor COUP-TFII. To understand cellular and molecular actions underlying Wolffian duct regression, we performed transcriptomic analyses of XX mesonephroi with or without Coup-tfII and genome-wide analysis of COUP-TFII chromatin occupancy in XX mesonephroi.
View Article and Find Full Text PDFSingle-cell RNA sequencing (scRNA-seq) technologies have precipitated the development of bioinformatic tools to reconstruct cell lineage specification and differentiation processes with single-cell precision. However, current start-up costs and recommended data volumes for statistical analysis remain prohibitively expensive, preventing scRNA-seq technologies from becoming mainstream. Here, we introduce single-cell amalgamation by latent semantic analysis (SALSA), a versatile workflow that combines measurement reliability metrics with latent variable extraction to infer robust expression profiles from ultra-sparse sc-RNAseq data.
View Article and Find Full Text PDFThe transcription factor forkhead box L2 (FOXL2) regulates sex differentiation and reproductive function. Elevated levels of this transcription factor have been observed in the diseases of the uterus, such as endometriosis. However, the impact of elevated FOXL2 expression on uterine physiology remains unknown.
View Article and Find Full Text PDFDevelopment and functions of the ovary rely on appropriate signaling and communication between various ovarian cell types. FOXL2, a transcription factor that plays a key role at different stages of ovarian development, is associated with primary ovarian insufficiency and ovarian cancer as a result of its loss-of-function or mutations. In this study, we investigated the impact of aberrant, constitutive expression of FOXL2 in somatic cells of the ovary.
View Article and Find Full Text PDFIn utero exposure to arsenite (iAs) is known to increase disease risks later in life. We investigated the effect of in utero exposure to iAs in the drinking water on metabolic and reproductive parameters in male mouse offspring at postnatal and adult stages. Pregnant CD-1 mice were exposed to iAs (as sodium arsenite) in the drinking water at 0 (control), 10 ppb (EPA standard for drinking water), and 42.
View Article and Find Full Text PDFThe flame retardant and plasticizer, tetrabromobisphenol-A (TBBPA) has rapidly become a common component in the manufacture of circuit boards and plastics worldwide. It is also an analog of bisphenol A (BPA), an endocrine disrupting chemical identified by the Endocrine Society. As such, TBBPA needs to be investigated for similar potential human health risks.
View Article and Find Full Text PDFMembers of the Iroquois B (IrxB) homeodomain cluster genes, specifically and , are crucial for heart, limb and bone development. Recently, we reported their importance for oocyte and follicle survival within the developing ovary. and expression begins after sex determination in the ovary but remains absent in the fetal testis.
View Article and Find Full Text PDFSex determination of the gonads begins with fate specification of gonadal supporting cells into either ovarian pre-granulosa cells or testicular Sertoli cells. This fate specification hinges on a balance of transcriptional control. Here we report that expression of the transcription factor RUNX1 is enriched in the fetal ovary in rainbow trout, turtle, mouse, goat, and human.
View Article and Find Full Text PDFAlfred Jost's work in the 1940s laid the foundation of the current paradigm of sexual differentiation of reproductive tracts, which contends that testicular hormones drive the male patterning of reproductive tract system whereas the female phenotype arises by default. Once established, the sex-specific reproductive tracts undergo morphogenesis, giving rise to anatomically and functionally distinct tubular organs along the rostral-caudal axis. Impairment of sexual differentiation of reproductive tracts by genetic alteration and environmental exposure are the main causes of disorders of sex development, and infertility at adulthood.
View Article and Find Full Text PDFThe identity of the gonads is determined by which fate, ovarian granulosa cell or testicular Sertoli cell, the bipotential somatic cell precursors choose to follow. In most vertebrates, the conserved transcription factor FOXL2 contributes to the fate of granulosa cells. To understand FOXL2 functions during gonad differentiation, we performed genome-wide analysis of FOXL2 chromatin occupancy in fetal ovaries and established a genetic mouse model that forces Foxl2 expression in the fetal testis.
View Article and Find Full Text PDF