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1.
Am J Hum Genet ; 108(2): 337-345, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33434492

RESUMO

Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) is associated with congenital absence of the uterus, cervix, and the upper part of the vagina; it is a sex-limited trait. Disrupted development of the Müllerian ducts (MD)/Wölffian ducts (WD) through multifactorial mechanisms has been proposed to underlie MRKHS. In this study, exome sequencing (ES) was performed on a Chinese discovery cohort (442 affected subjects and 941 female control subjects) and a replication MRKHS cohort (150 affected subjects of mixed ethnicity from North America, South America, and Europe). Phenotypic follow-up of the female reproductive system was performed on an additional cohort of PAX8-associated congenital hypothyroidism (CH) (n = 5, Chinese). By analyzing 19 candidate genes essential for MD/WD development, we identified 12 likely gene-disrupting (LGD) variants in 7 genes: PAX8 (n = 4), BMP4 (n = 2), BMP7 (n = 2), TBX6 (n = 1), HOXA10 (n = 1), EMX2 (n = 1), and WNT9B (n = 1), while LGD variants in these genes were not detected in control samples (p = 1.27E-06). Interestingly, a sex-limited penetrance with paternal inheritance was observed in multiple families. One additional PAX8 LGD variant from the replication cohort and two missense variants from both cohorts were revealed to cause loss-of-function of the protein. From the PAX8-associated CH cohort, we identified one individual presenting a syndromic condition characterized by CH and MRKHS (CH-MRKHS). Our study demonstrates the comprehensive utilization of knowledge from developmental biology toward elucidating genetic perturbations, i.e., rare pathogenic alleles involving the same loci, contributing to human birth defects.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual/genética , Anormalidades Congênitas/genética , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/crescimento & desenvolvimento , Mutação , Ductos Mesonéfricos/crescimento & desenvolvimento , Adulto , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 7/genética , Códon sem Sentido , Feminino , Estudos de Associação Genética , Pleiotropia Genética , Proteínas Homeobox A10/genética , Proteínas de Homeodomínio/genética , Humanos , Fator de Transcrição PAX8/genética , Herança Paterna , Penetrância , Proteínas com Domínio T/genética , Fatores de Transcrição/genética , Proteínas Wnt/genética , Ductos Mesonéfricos/anormalidades
2.
Differentiation ; 103: 66-73, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30236462

RESUMO

The urinary bladder collects urine from the kidneys and stores it until the appropriate moment for voiding. The trigone and ureterovesical junctions are key to bladder function, by allowing one-way passage of urine into the bladder without obstruction. Embryological development of these structures has been studied in multiple animal models as well as humans. In this report we review the existing literature on bladder development and cellular signalling with particular focus on bladder development in humans. The bladder and ureterovesical junction form primarily during the fourth to eighth weeks of gestation, and arise from the primitive urogenital sinus following subdivision of the cloaca. The bladder develops through mesenchymal-epithelial interactions between the endoderm of the urogenital sinus and mesodermal mesenchyme. Key signalling factors in bladder development include shh, TGF-ß, Bmp4, and Fgfr2. A concentration gradient of shh is particularly important in development of bladder musculature, which is vital to bladder function. The ureterovesical junction forms from the interaction between the Wolffian duct and the bladder. The ureteric bud arises from the Wolffian duct and is incorporated into the developing bladder at the trigone. It was previously thought that the trigonal musculature developed primarily from the Wolffian duct, but it has been shown to develop primarily from bladder mesenchyme. Following emergence of the ureters from the Wolffian ducts, extensive epithelial remodelling brings the ureters to their final trigonal positions via vitamin A-induced apoptosis. Perturbation of this process is implicated in clinical obstruction or urine reflux. Congenital malformations include ureteric duplication and bladder exstrophy.


Assuntos
Desenvolvimento Embrionário/genética , Rim/crescimento & desenvolvimento , Bexiga Urinária/crescimento & desenvolvimento , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Sistema Urogenital/crescimento & desenvolvimento
3.
Mech Dev ; 151: 10-17, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29626631

RESUMO

Eukaryotic cilia are assembled by intraflagellar transport (IFT) where large protein complexes called IFT particles move ciliary components from the cell body to the cilium. Defects in most IFT particle proteins disrupt ciliary assembly and cause mid gestational lethality in the mouse. IFT25 and IFT27 are unusual components of IFT-B in that they are not required for ciliary assembly and mutant mice survive to term. The mutants die shortly after birth with numerous organ defects including duplex kidneys. Completely duplex kidneys result from defects in ureteric bud formation at the earliest steps of metanephric kidney development. Ureteric bud initiation is a highly regulated process involving reciprocal signaling between the ureteric epithelium and the overlying metanephric mesenchyme with regulation by the peri-Wolffian duct stroma. The finding of duplex kidney in Ift25 and Ift27 mutants suggests functions for these genes in regulation of ureteric bud initiation. Typically the deletion of IFT genes in the kidney causes rapid cyst growth in the early postnatal period. In contrast, the loss of Ift25 results in smaller kidneys, which show only mild tubule dilations that become apparent in adulthood. The smaller kidneys appear to result from reduced branching in the developing metanephric kidney. This work indicates that IFT25 and IFT27 are important players in the early development of the kidney and suggest that duplex kidney is part of the ciliopathy spectrum.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Doenças Renais Císticas/genética , Rim/crescimento & desenvolvimento , Proteínas rab de Ligação ao GTP/genética , Animais , Cílios/genética , Cílios/patologia , Modelos Animais de Doenças , Humanos , Rim/patologia , Doenças Renais Císticas/patologia , Camundongos , Mutação , Organogênese/genética , Transdução de Sinais/genética , Ureter/crescimento & desenvolvimento , Ureter/patologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/patologia
4.
Differentiation ; 101: 25-38, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29684807

RESUMO

This study documented, for the first time, the morphological patterns of differentiation of male and female genital organs of Spix cavy (Galea spixii) using histological and ultrastructural analyses, with immuno-localization of steroidogenic enzymes, cytochromes P450 aromatase (P450arom) and 17α-hydroxylase/17, 20-lyase (P450c17), involved in the synthesis of estrogens and androgens respectively throughout fetal sexual development. Undifferentiated gonads of Spix cavy develop into ovaries in females after 25 days of gestation (DG), exhibiting P450arom immunoreactivity. After 25 DG, paramesonephric ducts develop and form oviducts, uterine horns and cranial portion of the vagina. The caudal portion of the vagina originates from the urogenital sinus, and a vaginal closure membrane is present at the end of gestation. Partial channeling of the urethra into the clitoris occurs after 40 DG, but complete channeling never occurs. A preputial meatus emerges near the tip of organ. In males, undifferentiated gonads develop into testes at 25 DG and develop immunoreactivity for P450c17, which is required for androgens synthesis and likely maintenance of mesonephric ducts. Mesonephric ducts develop subsequently, forming the epididymis and ductus deferens. The pelvic urethra develops after 25 DG with channeling into the penis occurring around 30 DG. This is the first morphological study describing the process of sexual differentiation during gestation in a hystricomorph rodent and one of the most comprehensive analyses conducted in any mammal. Male genital organ development follows the general pattern described in other domestic mammals, but does not include formation of the baculum as occurs in mice and rats. In females, clitoral development includes partial canalization by the urethra and development of a preputial meatus. Further studies are required to clarify the mechanisms involved in the differentiative processes described.


Assuntos
Ovário/crescimento & desenvolvimento , Diferenciação Sexual/fisiologia , Testículo/crescimento & desenvolvimento , Uretra/crescimento & desenvolvimento , Sistema Urogenital/crescimento & desenvolvimento , Animais , Feminino , Gônadas/crescimento & desenvolvimento , Cobaias , Masculino , Ductos Mesonéfricos/crescimento & desenvolvimento
5.
J Vis Exp ; (119)2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28117794

RESUMO

Tubal morphogenesis is a fundamental requirement for the development of most mammalian organs, including the male reproductive system. The epididymis, an integral part of the male reproductive tract, is responsible for sperm storage, maturation, and transport. The adult epididymis is a highly coiled tube that develops from a simple and straight embryonic precursor known as Wolffian duct (WD). Proper coiling of the epididymis is essential for male fertility, as sperm in the testis are unable to fertilize an oocyte. However, the mechanism responsible for epididymal development and coiling remains unclear, partially due to the lack of whole organ culture and imaging methods. In this study, we describe an in vitro culture system and whole mount immunofluorescence protocol to better visualize the process of WD coiling and development, which may also be applied to study other tubular organs.


Assuntos
Imunofluorescência , Técnicas de Cultura de Órgãos , Coloração e Rotulagem , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Epididimo/crescimento & desenvolvimento , Masculino , Camundongos , Morfogênese , Espermatozoides , Testículo
6.
Sci Rep ; 6: 23037, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26964900

RESUMO

Congenital reproductive tract anomalies could impair fertility. Female and male reproductive tracts are developed from Müllerian ducts and Wolffian ducts, respectively, involving initiation, elongation and differentiation. Genetic basis solely for distal reproductive tract development is largely unknown. Lhfpl2 (lipoma HMGIC fusion partner-like 2) encodes a tetra-transmembrane protein with unknown functions. It is expressed in follicle cells of ovary and epithelial cells of reproductive tracts. A spontaneous point mutation of Lhfpl2 (LHFPL2(G102E)) leads to infertility in 100% female mice, which have normal ovarian development, ovulation, uterine development, and uterine response to exogenous estrogen stimulation, but abnormal upper longitudinal vaginal septum and lower vaginal agenesis. Infertility is also observed in ~70% mutant males, which have normal mating behavior and sperm counts, but abnormal distal vas deferens convolution resulting in complete and incomplete blockage of reproductive tract in infertile and fertile males, respectively. On embryonic day 15.5, mutant Müllerian ducts and Wolffian ducts have elongated but their duct tips are enlarged and fail to merge with the urogenital sinus. These findings provide a novel function of LHFPL2 and a novel genetic basis for distal reproductive tract development; they also emphasize the importance of an additional merging phase for proper reproductive tract development.


Assuntos
Genitália/crescimento & desenvolvimento , Genitália/metabolismo , Perda Auditiva Neurossensorial/metabolismo , Infertilidade Feminina/genética , Reprodução/genética , Animais , Feminino , Perda Auditiva Neurossensorial/genética , Infertilidade Feminina/patologia , Masculino , Camundongos , Ductos Paramesonéfricos/crescimento & desenvolvimento , Ductos Paramesonéfricos/metabolismo , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Mutação Puntual , Diferenciação Sexual/genética , Sistema Urogenital/crescimento & desenvolvimento , Sistema Urogenital/metabolismo , Sistema Urogenital/patologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo
7.
Pediatr Nephrol ; 31(6): 885-95, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26293980

RESUMO

Fibroblast growth factor receptors (FGFRs) and FGF ligands are highly expressed in the developing kidney and lower urinary tract. Several classic studies showed many effects of exogenous FGF ligands on embryonic renal tissues in vitro and in vivo. Another older landmark publication showed that mice with a dominant negative Fgfr fragment had severe renal dysplasia. Together, these studies revealed the importance of FGFR signaling in kidney and lower urinary tract development. With the advent of modern gene targeting techniques, including conditional knockout approaches, several publications have revealed critical roles for FGFR signaling in many lineages of the kidney and lower urinary tract at different stages of development. FGFR signaling has been shown to be critical for early metanephric mesenchymal patterning, Wolffian duct patterning including induction of the ureteric bud, ureteric bud branching morphogenesis, nephron progenitor survival and nephrogenesis, and bladder mesenchyme patterning. FGFRs pattern these tissues by interacting with many other growth factor signaling pathways. Moreover, the many genetic Fgfr and Fgf animal models have structural defects mimicking numerous congenital anomalies of the kidney and urinary tract seen in humans. Finally, many studies have shown how FGFR signaling is critical for kidney and lower urinary tract patterning in humans.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Rim/crescimento & desenvolvimento , Organogênese , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Ureter/crescimento & desenvolvimento , Bexiga Urinária/crescimento & desenvolvimento , Ductos Mesonéfricos/crescimento & desenvolvimento , Acantose Nigricans/genética , Acantose Nigricans/metabolismo , Acrocefalossindactilia/genética , Acrocefalossindactilia/metabolismo , Animais , Fenótipo de Síndrome de Antley-Bixler/genética , Fenótipo de Síndrome de Antley-Bixler/metabolismo , Apoptose , Craniossinostoses/genética , Craniossinostoses/metabolismo , Orelha/anormalidades , Técnicas de Inativação de Genes/métodos , Humanos , Rim/metabolismo , Rim/patologia , Camundongos , Modelos Animais , Mutação , Organogênese/genética , Receptores de Fatores de Crescimento de Fibroblastos/genética , Dermatoses do Couro Cabeludo/genética , Dermatoses do Couro Cabeludo/metabolismo , Transdução de Sinais , Anormalidades da Pele/genética , Anormalidades da Pele/metabolismo , Proteínas com Domínio T/genética , Ureter/metabolismo , Ureter/patologia , Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Ductos Mesonéfricos/metabolismo
8.
Biol Reprod ; 93(4): 90, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26333992

RESUMO

Leucine-rich repeat-containing G protein-coupled receptor 4 (Lgr4) is a type of membrane receptor with a seven-transmembrane structure. LGR4 is homologous to gonadotropin receptors, such as follicle-stimulating hormone receptor (Fshr) and luteinizing hormone/choriogonadotropin receptor (Lhcgr). Recently, it has been reported that Lgr4 is a membrane receptor for R-spondin ligands, which mediate Wnt/beta-catenin signaling. Defects of R-spondin homolog (Rspo1) and wingless-type MMTV integration site family, member 4 (Wnt4) cause masculinization of female gonads. We observed that Lgr4(-/-) female mice show abnormal development of the Wolffian ducts and somatic cells similar to that in the male gonads. Lgr4(-/-) female mice exhibited masculinization similar to that observed in Rspo1-deficient mice. In Lgr4(-/-) ovarian somatic cells, the expression levels of lymphoid enhancer-binding factor 1 (Lefl) and Axin2 (Axin2), which are target genes of Wnt/beta-catenin signaling, were lower than they were in wild-type mice. This study suggests that Lgr4 is critical for ovarian somatic cell specialization via the cooperative signaling of Rspo1 and Wnt/beta-catenin.


Assuntos
Ovário/crescimento & desenvolvimento , Ovário/fisiologia , Receptores Acoplados a Proteínas-G/genética , Receptores Acoplados a Proteínas-G/fisiologia , Animais , Proteína Axina/biossíntese , Proteína Axina/genética , Ciclo Estral/genética , Ciclo Estral/fisiologia , Feminino , Hormônios Esteroides Gonadais/biossíntese , Fator 1 de Ligação ao Facilitador Linfoide/biossíntese , Fator 1 de Ligação ao Facilitador Linfoide/genética , Camundongos , Camundongos Knockout , Ovário/citologia , Gravidez , Diferenciação Sexual/genética , Superovulação/genética , Superovulação/fisiologia , Trombospondinas/genética , Trombospondinas/fisiologia , Via de Sinalização Wnt/genética , Ductos Mesonéfricos/crescimento & desenvolvimento
9.
Hum Mol Genet ; 23(25): 6807-14, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25082826

RESUMO

Congenital anomalies of the kidney and urinary tract (CAKUT) affect about 1 in 500 births and are a major cause of morbidity in infants. Duplex collecting systems rank among the most common abnormalities of CAKUT, but the molecular basis for this defect is poorly understood. In mice, conditional deletion of Wnt5a in mesoderm results in bilateral duplex kidney and ureter formation. The ureteric buds (UBs) in mutants emerge as doublets from the intermediate mesoderm (IM)-derived nephric duct (ND) without anterior expansion of the glial cell line-derived neurotrophic factor (Gdnf) expression domain in the surrounding mesenchyme. Wnt5a is normally expressed in a graded manner at the posterior end of the IM, but its expression is down-regulated prior to UB outgrowth at E10.5. Furthermore, ablation of Wnt5a in the mesoderm with an inducible Cre at E7.5 results in duplex UBs, whereas ablation at E8.5 yields normal UB outgrowth, demonstrating that Wnt5a functions in IM development well before the formation of the metanephros. In mutants, the posterior ND is duplicated and surrounding Pax2-positive mesenchymal cells persist in the nephric cord, suggesting that disruption of normal ND patterning prompts the formation of duplex ureters and kidneys. Ror2 homozygous mutants, which infrequently yield duplex collecting systems, show a dramatic increase in incidence with the additional deletion of one copy of Wnt5a, implicating this receptor in non-canonical Wnt5a signaling during IM development. This work provides the first evidence of a role of Wnt5a/Ror2 signaling in IM extension and offers new insights into the etiology of CAKUT and possible involvement of Wnt5a/Ror2 mutations.


Assuntos
Rim/metabolismo , Mesoderma/metabolismo , Morfogênese/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/genética , Transdução de Sinais/genética , Proteínas Wnt/genética , Animais , Embrião de Mamíferos , Regulação da Expressão Gênica no Desenvolvimento , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Homozigoto , Integrases/genética , Integrases/metabolismo , Rim/crescimento & desenvolvimento , Rim/patologia , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Mesoderma/crescimento & desenvolvimento , Mesoderma/patologia , Camundongos , Camundongos Transgênicos , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Fatores de Tempo , Ureter/crescimento & desenvolvimento , Ureter/metabolismo , Ureter/patologia , Proteínas Wnt/deficiência , Proteína Wnt-5a , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo , Ductos Mesonéfricos/patologia
10.
Int J Dev Biol ; 58(9): 663-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25896202

RESUMO

The Müllerian duct gives rise to female reproductive organs, such as the oviduct and uterus. During gestation, the Wolffian duct, which generates male reproductive organs and the kidney, is formed, and the Müllerian duct then elongates caudally along the preformed Wolffian duct. Anatomical separation of these two ducts in chick embryos demonstrated that the Wolffian duct is required for Müllerian duct formation. Likewise, a few reports supported this notion in mice, including studies on Wnt9b mutant mice and Wolffian duct-specific Lhx1 deletion. However, anatomical ablation of the Wolffian duct has not been established in mice. In this study, we addressed the importance of the interaction between these two reproductive ducts, by generating mice that specifically expressed a diphtheria toxin subunit in the Wolffian duct. While this genetic ablation of the Wolffian duct resulted in kidney hypoplasia/agenesis in both male and female mutant mice, the female mutant mice lacked the uterus, which is derived from the Müllerian duct. At mid-gestation, the Müllerian duct was truncated at the level where the mutant Wolffian duct was prematurely terminated, meaning that Müllerian duct elongation was dependent on the preformed Wolffian duct. However, Wnt9b expression in the Wolffian duct and the resultant canonical Wnt activity, as well as Lhx1 expression, were not affected in the mutant mice. These results suggest that the Wolffian duct regulates Müllerian duct elongation by currently unidentified mechanisms that are independent of canonical Wnt signaling or Lhx1 expression.


Assuntos
Embrião de Mamíferos/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Ductos Paramesonéfricos/crescimento & desenvolvimento , Organogênese , Fatores de Transcrição/metabolismo , Útero/metabolismo , Proteínas Wnt/metabolismo , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Embrião de Mamíferos/citologia , Feminino , Técnicas Imunoenzimáticas , Hibridização In Situ , Proteínas com Homeodomínio LIM/genética , Masculino , Camundongos , Camundongos Knockout , Ductos Paramesonéfricos/embriologia , Ductos Paramesonéfricos/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Útero/embriologia , Proteínas Wnt/genética , Ductos Mesonéfricos/embriologia , Ductos Mesonéfricos/metabolismo
11.
Mech Dev ; 130(9-10): 506-18, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23542432

RESUMO

Glial cell line-derived neurotrophic factor (GDNF) binds a coreceptor GDNF family receptor α1 (GFRα1) and forms a signaling complex with the receptor tyrosine kinase RET. GDNF-GFRα1-RET signaling activates cellular pathways that are required for normal induction of the ureteric bud (UB) from the Wolffian duct (WD). Failure of UB formation results in bilateral renal agenesis and perinatal lethality. Gfrα1 is expressed in both the epithelial and mesenchymal compartments of the developing kidney while Ret expression is specific to the epithelium. The biological importance of Gfrα1's wider tissue expression and its role in later kidney development are unclear. We discovered that conditional loss of Gfrα1 in the WD epithelium prior to UB branching is sufficient to cause renal agenesis. This finding indicates that Gfrα1 expressed in the nonepithelial structures cannot compensate for this loss. To determine Gfrα1's role in branching morphogenesis after UB induction we used an inducible Gfrα1-specific Cre-deletor strain and deleted Gfrα1 from the majority of UB tip cells post UB induction in vivo and in explant kidney cultures. We report that Gfrα1 excision from the epithelia compartment after UB induction caused a modest reduction in branching morphogenesis. The loss of Gfrα1 from UB-tip cells resulted in reduced cell proliferation and decreased activated ERK (pERK). Further, cells without Gfrα1 expression are able to populate the branching UB tips. These findings delineate previously unclear biological roles of Gfrα1 in the urinary tract and demonstrate its cell-type and stage-specific requirements in kidney development.


Assuntos
Anormalidades Congênitas/genética , Células Epiteliais/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Nefropatias/congênito , Rim/anormalidades , Rim/metabolismo , Mesoderma/metabolismo , Ureter/metabolismo , Animais , Proliferação de Células , Anormalidades Congênitas/metabolismo , Embrião de Mamíferos , Células Epiteliais/citologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Rim/citologia , Rim/crescimento & desenvolvimento , Nefropatias/genética , Nefropatias/metabolismo , Masculino , Mesoderma/citologia , Mesoderma/crescimento & desenvolvimento , Camundongos , Camundongos Transgênicos , Organogênese/genética , Proteínas Proto-Oncogênicas c-ret/genética , Proteínas Proto-Oncogênicas c-ret/metabolismo , Transdução de Sinais , Técnicas de Cultura de Tecidos , Ureter/citologia , Ureter/crescimento & desenvolvimento , Ductos Mesonéfricos/citologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo
12.
Development ; 138(24): 5369-78, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22110055

RESUMO

During development of the urogenital tract, fibroblast growth factor 8 (Fgf8) is expressed in mesonephric tubules, but its role in this tissue remains undefined. An evaluation of previously generated T-Cre-mediated Fgf8-deficient mice (T-Cre; Fgf8(flox/Δ2,3) mice), which lack Fgf8 expression in the mesoderm, revealed that the cranial region of the Wolffian duct degenerated prematurely and the cranial mesonephric tubules were missing. As a result, the epididymis, vas deferens and efferent ductules were largely absent in mutant mice. Rarb2-Cre was used to eliminate FGF8 from the mesonephric tubules but to allow expression in the adjacent somites. These mutants retained the cranial end of the Wolffian duct and formed the epididymis and vas deferens, but failed to elaborate the efferent ductules, indicating that Fgf8 expression by the mesonephric tubules is required specifically for the formation of the ductules. Ret knockout mice do not form the ureteric bud, a caudal outgrowth of the Wolffian duct and progenitor for the collecting duct network in the kidney, but they do develop the cranial end normally. This indicates that Fgf8, but not Ret, expression is essential to the outgrowth of the cranial mesonephric tubules from the Wolffian duct and to the development of major portions of the sex accessory tissues in the male reproductive tract. Mechanistically, FGF8 functions upstream of Lhx1 expression in forming the nephron, and analysis of Fgf8 mutants similarly shows deficient Lhx1 expression in the mesonephric tubules. These results demonstrate a multifocal requirement for FGF8 in establishing the male reproductive tract ducts and implicate Lhx1 signaling in tubule elongation.


Assuntos
Fator 8 de Crescimento de Fibroblasto/metabolismo , Genitália Masculina/crescimento & desenvolvimento , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Regulação da Expressão Gênica no Desenvolvimento , Genitália Masculina/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Masculino , Mesoderma/crescimento & desenvolvimento , Mesoderma/metabolismo , Camundongos , Camundongos Knockout , Néfrons/crescimento & desenvolvimento , Néfrons/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Fatores de Transcrição/metabolismo , Sistema Urogenital/crescimento & desenvolvimento , Sistema Urogenital/metabolismo , Ductos Mesonéfricos/metabolismo
13.
J Androl ; 32(6): 558-64, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21441421

RESUMO

It is very clear that the epididymis plays a crucial role in the maturation of spermatozoa, and without a fully developed and functional epididymis, male infertility will result. We are especially interested in understanding the mechanisms that regulate the development of this important organ because disruptions to epididymal function will also arise as a consequence of abnormal development. Very little is known either of the process of epididymal development or the nature and causes of congenital defects that lead to male infertility. A major event during Wolffian/epididymal duct embryonic development is elongation and coiling and this short review outlines potential mechanisms by which these events occur. It is hypothesized that elongation is the result of cell proliferation coupled with directed cell rearrangements, the later regulated by the planar cell polarity signaling pathway. Coiling proceeds in a proximal to distal manner, with three-dimensional coiling beginning approximately embryonic day 16.5 to 18.5 in the mouse. The exact mechanisms of coiling are not known but we hypothesize that it involves an interaction between the Wolffian duct epithelium and the surrounding mesenchyme cells, such that the extracellular matrix is remodeled to allow coiling and growth of the duct. Cell proliferation in the Wolffian duct appears to be dependent on the presence of androgens and mesenchymal factors during embryonic development, but lumicrine factors play an additional role during postnatal development.


Assuntos
Epididimo/anatomia & histologia , Escroto/anatomia & histologia , Androgênios/metabolismo , Animais , Proliferação de Células , Epididimo/embriologia , Epididimo/crescimento & desenvolvimento , Epididimo/metabolismo , Matriz Extracelular/metabolismo , Humanos , Masculino , Mesoderma/embriologia , Mesoderma/crescimento & desenvolvimento , Camundongos , Escroto/embriologia , Escroto/crescimento & desenvolvimento , Escroto/metabolismo , Ductos Mesonéfricos/embriologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo
14.
Dev Biol ; 334(2): 429-36, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19664614

RESUMO

In developing mammalian males, conversion of the Wolffian ducts into the epididymides and vasa deferentia depends on androgen secretion by the testes, whereas in females these ducts remain in a vestigial form or regress. However, there is continuing uncertainty whether the androgen needs to be delivered locally, either by diffusion from the adjacent testis or, by secretion into the lumen of the duct, or whether circulating androgens maintain and virilize the Wolffian ducts. To resolve this uncertainty, we transplanted either day 0-2 or day 8-9 post-partum testes beneath the flank skin of three groups of neonatal (days 0-1) female tammar wallabies, where they developed and secreted physiological levels of hormones. The Wolffian ducts of all these females were retained and had formed extensive epididymides when examined at days 25, 34 and 87 after birth. In the two older groups of females, sampled after the time of prostatic bud formation, the urogenital sinus was virilized and there was extensive prostatic development similar to that of normal males of the same age, showing that androgen secretion had occurred. Virilization of the Wolffian ducts occurred during an early but short-lived window of sensitivity. This study provides the first clear evidence that under physiological conditions virilization can be mediated by circulating androgen.


Assuntos
Androgênios/fisiologia , Diferenciação Sexual/fisiologia , Testículo/metabolismo , Sistema Urogenital/crescimento & desenvolvimento , Virilismo/etiologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Androgênios/sangue , Androgênios/metabolismo , Animais , Animais Recém-Nascidos , Epididimo/crescimento & desenvolvimento , Feminino , Macropodidae , Masculino , Morfogênese , Ductos Paramesonéfricos/crescimento & desenvolvimento , Próstata/crescimento & desenvolvimento , Tela Subcutânea , Testículo/transplante , Fatores de Tempo , Transplante Heterólogo , Virilismo/fisiopatologia
15.
PLoS Genet ; 4(12): e1000316, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19112489

RESUMO

Metanephric kidney induction critically depends on mesenchymal-epithelial interactions in the caudal region of the nephric (or Wolffian) duct. Central to this process, GDNF secreted from the metanephric mesenchyme induces ureter budding by activating the Ret receptor expressed in the nephric duct epithelium. A failure to regulate this pathway is believed to be responsible for a large proportion of the developmental anomalies affecting the urogenital system. Here, we show that the nephric duct-specific inactivation of the transcription factor gene Gata3 leads to massive ectopic ureter budding. This results in a spectrum of urogenital malformations including kidney adysplasia, duplex systems, and hydroureter, as well as vas deferens hyperplasia and uterine agenesis. The variability of developmental defects is reminiscent of the congenital anomalies of the kidney and urinary tract (CAKUT) observed in human. We show that Gata3 inactivation causes premature nephric duct cell differentiation and loss of Ret receptor gene expression. These changes ultimately affect nephric duct epithelium homeostasis, leading to ectopic budding of interspersed cells still expressing the Ret receptor. Importantly, the formation of these ectopic buds requires both GDNF/Ret and Fgf signaling activities. We further identify Gata3 as a central mediator of beta-catenin function in the nephric duct and demonstrate that the beta-catenin/Gata3 pathway prevents premature cell differentiation independently of its role in regulating Ret expression. Together, these results establish a genetic cascade in which Gata3 acts downstream of beta-catenin, but upstream of Ret, to prevent ectopic ureter budding and premature cell differentiation in the nephric duct.


Assuntos
Fator de Transcrição GATA3/metabolismo , Rim/embriologia , Transdução de Sinais , Ductos Mesonéfricos/anormalidades , beta Catenina/metabolismo , Animais , Diferenciação Celular , Linhagem Celular , Fator de Transcrição GATA3/genética , Humanos , Rim/anormalidades , Rim/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ureter/anormalidades , Ureter/citologia , Ureter/metabolismo , Ductos Mesonéfricos/embriologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo , beta Catenina/genética
16.
Endocrinology ; 148(7): 3185-95, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17431008

RESUMO

Androgens are thought to separately regulate stabilization and differentiation of the Wolffian duct (WD), but the time windows for these effects are unclear. To address this, fetal rats were exposed to flutamide within either an early window (EW) [embryonic day 15.5 (E15.5) to E17.5], when the WD degenerates in the female, or a later window (LW) (E19.5-E21.5), when the WD morphologically differentiates in the male, or during the full window of WD development (FW) (E15.5-21.5). WDs were examined for abnormalities during fetal (E21.5) or postnatal life, and anogenital distance and prostate presence/absence were recorded. Exposure to FW- or EW-flutamide, but not to LW-flutamide, induced comparable abnormalities in the fetal WD at E21.5, namely reduced WD coiling, reduced cell proliferation, reduced epithelial cell height, altered epithelial vimentin expression, and reduced expression of smooth muscle actin in the WD inner stroma. Exposure to EW- or FW-flutamide, but not to LW-flutamide, resulted in incomplete/absent WDs in more than 50% of males by adulthood, although such abnormalities were infrequent in fetal life. These findings suggest that androgen action during the EW is sufficient to promote WD morphological differentiation several days later. Because the androgen receptor is expressed in the WD stroma but not in the epithelium during this EW, WD differentiation is likely to be dependent on androgen-mediated signaling from the stroma to the epithelium. In conclusion, the critical window for androgen action in regulating WD development in the rat is between E15.5 and E17.5. This window is also important for prostate formation and anogenital distance masculinization.


Assuntos
Androgênios/metabolismo , Flutamida/farmacologia , Ductos Mesonéfricos/efeitos dos fármacos , Antagonistas de Androgênios/farmacologia , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Imuno-Histoquímica , Queratinas/metabolismo , Masculino , Gravidez , Distribuição Aleatória , Ratos , Ratos Wistar , Receptores Androgênicos/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Fatores de Tempo , Vimentina/metabolismo , Ductos Mesonéfricos/embriologia , Ductos Mesonéfricos/crescimento & desenvolvimento
17.
Curr Opin Nephrol Hypertens ; 16(1): 3-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17143064

RESUMO

PURPOSE OF REVIEW: A set of important genes and signaling pathways involved in kidney development is emerging from analyses of mutant mice, in-vitro models, and global gene expression patterns. Conversion of data into dynamic models or networks through the synthesis of information at multiple levels is crucial for a better understanding of kidney development. RECENT FINDINGS: Genetic and in-vitro evidence is beginning to provide a limited sense of the network topology in stages of kidney development. Intriguing data from other fields suggest how, with the aid of large-scale gene expression studies, these stages might be represented as dynamic attractor states. It is also suggested how branching morphogenesis of the epithelial ureteric bud may be sustained by an autocatalytic set of proteins whose interactions lead to repeated rounds of tip and stalk generation. Accumulating data in lower organisms suggest network topologies may be quite flexible, and the implications of these results for varieties of tubulogenesis and renal regeneration after acute injury are discussed. SUMMARY: Currently it may be feasible to build tentative dynamic multistage models of nephrogenesis that facilitate experimental thinking. As data accumulate, it may become possible to test their predictive value.


Assuntos
Rim/embriologia , Animais , Rim/anatomia & histologia , Rim/fisiologia , Organogênese/genética , Organogênese/fisiologia , Regeneração/genética , Regeneração/fisiologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/metabolismo
18.
Endocrinology ; 147(10): 4820-30, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16809447

RESUMO

Androgens play a vital role in Wolffian duct (WD) development, but the mechanisms that underlie this are unknown. The present study used in utero exposure of pregnant rats to the androgen receptor antagonist flutamide (50 or 100 mg/kg) to explore possible mechanisms. Pregnant rats were treated from embryonic d 15.5 (E15.5), and WDs were isolated from fetuses from E17.5-E21.5 and from adults. WD morphology was evaluated, and total length of the duct lumen was determined in fetal samples. Fetal WDs were immunostained for androgen receptor and stromal (inner and outer) and/or epithelial-cell-specific markers and analyzed for cell proliferation and apoptosis. In adulthood, most flutamide-exposed males lacked proximal WD-derived tissues, whereas at E18.5-E19.5, a time when the WD has completely regressed in females, a complete normal WD was present in all flutamide-exposed animals. This suggests that flutamide, at doses of 50 or 100 mg/kg, interferes with WD differentiation, not stabilization. Consistent with this, WD elongation/coiling increased in controls by 204% between E19.5 and E21.5 but increased less significantly (103%) in flutamide-exposed animals. This was associated with reduced cell proliferation, but there was no increase in apoptosis or change in expression of androgen receptor mRNA or protein. Flutamide treatment impaired differentiation of inner stromal cells, shown by decreased expression of smooth muscle actin, before effects were noted in the epithelium, consistent with androgens driving WD development via stromal-epithelial interactions. In conclusion, WD differentiation is far more susceptible to blockade of androgen action than is its initial stabilization, and these effects may be mediated by disruption of stromal-epithelial interactions.


Assuntos
Antagonistas de Androgênios/farmacologia , Androgênios/fisiologia , Flutamida/farmacologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Feminino , Imunofluorescência , Genitália Masculina/efeitos dos fármacos , Genitália Masculina/crescimento & desenvolvimento , Imuno-Histoquímica , Masculino , Mitose/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Receptores Androgênicos/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/efeitos dos fármacos , Ductos Mesonéfricos/efeitos dos fármacos
19.
Mol Endocrinol ; 20(7): 1535-46, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16513791

RESUMO

In utero exposure to diethylstilbestrol (DES) leads to patterning defects in the female reproductive tract (FRT) and a propensity to the development of vaginal adenocarcinomas in humans. In the mouse, DES treatment similarly induces a plethora of FRT developmental defects, including stratification of uterine epithelium and presence of glandular tissue in cervix and vagina. Uterine abnormalities are associated with repression of the homeobox gene Msx2, and DES leads to an altered uterine response in Msx2 mutants including a dilated uterine lumen. Here we investigate the role of Msx2 in normal vaginal development and in FRT response to DES. During vaginal development, Msx2 is required for Tgfbeta2 and Tgfbeta3 expression and for proper vaginal epithelial differentiation. Moreover, Msx2 is involved in caudal Wolffian duct regression by promoting apoptosis. Consistently, neonatal DES exposure represses Msx2 expression in the Wolffian duct epithelium and inhibits its apoptosis and subsequent regression. Intriguingly, although DES treatment also represses Msx2 expression in the vaginal epithelium, a much more severe DES-induced vaginal phenotype was observed in Msx2 mutant mice, including a complete failure of Müllerian vaginal epithelial stratification and a severely dilated vaginal lumen, accompanied by loss of p63 and water channel protein expression. These results demonstrate a critical role for Msx2 in counteracting the effect of DES on FRT patterning and suggest that the response to DES may be highly variable depending on the genotype of an individual.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Dietilestilbestrol/efeitos adversos , Proteínas de Homeodomínio/fisiologia , Vagina/citologia , Vagina/efeitos dos fármacos , Ductos Mesonéfricos/efeitos dos fármacos , Ductos Mesonéfricos/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados , Aquaporinas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Células Epiteliais/efeitos dos fármacos , Feminino , Proteínas de Homeodomínio/metabolismo , Camundongos , Camundongos Mutantes , Vagina/crescimento & desenvolvimento
20.
Horm Res ; 65(4): 200-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16567946

RESUMO

BACKGROUND: Wolffian ducts (WDs) are the embryonic precursors of the male reproductive tract. Their development is induced by testosterone, which interacts with the androgen receptor (AR). The molecular pathways underlying androgen-dependent WD development are largely unknown. We aimed to identify AR target genes important in this process. METHODS: RNA was isolated from rat WDs at E17.5 and E20.5. Affymetrix GeneChip expression arrays were used to identify transcripts up- or downregulated more than 2-fold. Regulation of seven transcripts was confirmed using quantitative PCR. RESULTS: Transcripts from 76 known genes were regulated, including modulators of insulin-like growth factor and transforming growth factor-beta signalling. By controlling these modulators, androgens may indirectly affect growth factor signalling pathways important in epithelial-mesenchymal interactions and organ development. Caveolin-1, also upregulated, may play a role in modifying as well as mediating AR signalling. Differentiation of WD epithelium and smooth muscle, innervation and extracellular matrix synthesis were reflected in regulation of other transcripts. Several genes were previously suggested to be regulated by androgens or contained functional or putative androgen/glucocorticoid response elements, indicating they may be direct targets of androgen signalling. CONCLUSION: Our results suggest novel cohorts of signals that may contribute to androgen-dependent WD development and provide hypotheses that can be tested by future studies.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Receptores Androgênicos/fisiologia , Ductos Mesonéfricos/crescimento & desenvolvimento , Ductos Mesonéfricos/fisiologia , Androgênios/fisiologia , Animais , Caveolina 1/genética , Caveolina 1/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Cistatinas , DNA/análise , DNA/genética , Feminino , Masculino , Músculo Liso/citologia , Músculo Liso/crescimento & desenvolvimento , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Reação em Cadeia da Polimerase , Proteínas/genética , Proteínas/fisiologia , RNA/análise , Ratos , Ratos Wistar , Receptores Androgênicos/genética , Elementos de Resposta/genética , Elementos de Resposta/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Somatomedinas/genética , Somatomedinas/fisiologia , Testosterona/fisiologia , Transcrição Genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia , Ductos Mesonéfricos/química , Ductos Mesonéfricos/citologia
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