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Blanche Capel - One of the best experts on this subject based on the ideXlab platform.
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numb regulates somatic cell lineage commitment during early gonadogenesis in mice
Development, 2017Co-Authors: Yitzu Lin, Lindsey Barske, Tony Defalco, Blanche CapelAbstract:During early gonadogenesis, proliferating cells in the Coelomic Epithelium (CE) give rise to most of the somatic cells in both XX and XY gonads. Previous dye-labeling experiments showed that a single CE cell could give rise to additional CE cells and to both supporting and interstitial cell lineages, implying that cells in the CE domain are multipotent progenitors, and suggesting that an asymmetric division is involved in the acquisition of gonadal cell fates. We found that NUMB is asymmetrically localized in CE cells, suggesting that it might be involved. To test this hypothesis, we conditionally deleted Numb on a Numbl mutant background just prior to gonadogenesis. Mutant gonads showed a loss of cell polarity in the surface epithelial layers, large interior cell patches expressing the undifferentiated cell marker LHX9, and a loss of differentiated cells in somatic cell lineages. These results indicate that NUMB is necessary for establishing polarity in CE cells, and that asymmetric divisions resulting from CE polarity are required for commitment to differentiated somatic cell fates. Surprisingly, germ cells, which do not arise from the CE, were also affected in mutants, which may be a direct or indirect effect of loss of Numb.
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ARTICLE NO. DB989068 Sertoli Cells of the Mouse Testis Originate
2013Co-Authors: From The Coelomic Epithelium, Jeannie Karl, Blanche CapelAbstract:During mouse development, the gonad begins to form shortly before 10.5 days postcoitum (dpc) on the ventromedial side of the mesonephros. The XY gonad consists of germ cells and somatic cells. The origin of the germ cells is clearly established; however, the origin of the somatic cells, especially the epithelial supporting cell lineages, called Sertoli cells, is still unclear. Sertoli cells are the first somatic cell type to differentiate in the testis and are thought to express Sry, the male sex-determining gene, and to play a crucial role in directing testis development. Previous data have suggested that the somatic cells of the gonad may arise from the mesonephric tubules, the mesonephric mesenchyme, or the Coelomic Epithelium. Immunohistochemical staining of the gonad at 11.5 dpc showed that the basement membrane barrier under the Coelomic Epithelium is discontinuous, suggesting that cells in the Coelomic Epithelium at this stage might move inward. To test this possibility directly, cells of the Coelomic Epithelium were labeled using the fluorescent lipophilic dye, DiI. We show that when labeled at tail somite 15–17 stages, corresponding to 11.2–11.4 dpc, the Coelomic epithelial cells of both sexes migrated into the gonad. In XY gonads, the migrating Coelomic epithelial cells became Sertoli cells, as well as interstitial cells. This ability of the Coelomic Epithelium to give rise to Sertoli cells was developmentally regulated. When labeled at tail somite 18–20 stages, corresponding to 11.5–11.7 dpc, the Coelomic epithelial cells no longer became Sertoli cells. Instead, cells that migrated into the gonad stayed outside testis cords, in the interstitium. Migration gradually decreased and ceased by tail somite 30 stage, corresponding to 12.5 dpc, after testis cords had formed and the basemen
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cellular mechanisms of sex determination in the red eared slider turtle trachemys scripta
Mechanisms of Development, 2004Co-Authors: Humphrey H C Yao, Leo Dinapoli, Blanche CapelAbstract:In all vertebrates sex determination is the step at which development of a testis or ovary is initiated in the bipotential gonad. Although Mus musculus and the red-eared slider turtle, Trachemys scripta, use different mechanisms to initiate organogenesis of the testis (the Y-linked gene, Sry, in the mouse vs. the incubation temperature of the egg in the turtle), the structure of the adult testis is strikingly similar. We have identified several cellular mechanisms involved in testis organogenesis in mouse. Here we investigated whether these cellular mechanisms are conserved in T. scripta downstream of the temperature-dependent switch. Cell tracing experiments indicated that the Coelomic Epithelium in T. scripta contributes precursors for Sertoli cells and interstitial cells as in mouse. However, we detect no male-specific mesonephric cell migration, a process required for the de novo testis cord-forming process in mouse. In contrast to mouse gonads, where no cord structure is discernible until after the divergence of testis development, we find that primitive sex cords continuous with the Coelomic Epithelium exist in all T. scripta gonads from the earliest bipotential stages examined. We conclude that typical testis architecture results from the maintenance and elaboration of primitive sex cords in T. scripta rather than the assembly of de novo structures as in mouse.
Bodil Hernroth - One of the best experts on this subject based on the ideXlab platform.
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Manganese effects on haematopoietic cells and circulating coelomocytes of Asterias rubens (Linnaeus).
Aquatic Toxicology, 2008Co-Authors: Carolina Oweson, Helen Nilsson Skold, Annalisa Pinsino, Valeria Matranga, Bodil HernrothAbstract:Abstract Manganese (Mn) is a naturally abundant metal in marine sediments where it mainly occurs as MnO 2 . During hypoxic conditions it is converted into a bioavailable state, Mn 2+ , and can reach levels that previously have shown effects on immune competent cells of the crustacean, Nephrops norvegicus . Here we investigated if Mn also affects circulating coelomocytes and their renewal in the common sea star, Asterias rubens , when exposed to concentrations of Mn that can be found in nature. When the sea stars were exposed to Mn it accumulated in the Coelomic fluid and the number of circulating coelomocytes, in contrast to what was recorded in Nephrops , increased significantly. By using the substitute nucleotide, 5-bromo-2′-deoxyuridine, BrdU, for tracing cell division and by recording mitotic index by nuclei staining, we found that Mn induced proliferation of cells from a putative haematopoietic tissue, the Coelomic Epithelium. In addition, the haematopoietic tissue and coelomocytes showed stress response in terms of changes in HSP70 levels and protein carbonyls, as judged by immunohistochemistry and Western blotting. Measurement of dehydrogenase activity, using MTS/PMS, revealed that Mn showed cytotoxic properties. We also found that the phagocytotic capacity of coelomocytes was significantly inhibited by Mn. It was concluded that the exposure of A. rubens to Mn induced renewal of coelomocytes and impaired their immune response.
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induced cell proliferation in putative haematopoietic tissues of the sea star asterias rubens l
The Journal of Experimental Biology, 2008Co-Authors: Kristina Holm, Sam Dupont, Helen Nilsson Skold, Anna Stenius, Michael C Thorndyke, Bodil HernrothAbstract:The Coelomic fluid of the echinoderm Asterias rubens possesses large populations of circulating coelomocytes. This study aimed to expand the knowledge about the haematopoietic sources of these cells. Injection of the immune-stimulating molecules lipopolysaccharide (LPS) and concanavalin A (ConA) resulted in an increase in coelomocytes. To investigate if these molecules induce cell proliferation in putative haematopoietic tissues (HPTs), short-term exposure of the substitute nucleotide 5-bromo-2'-deoxyuridine (BrdU) was conducted. Immunohistochemical analysis, using fluorescein-labelled antibodies to trace BrdU, showed pronounced cell division in the Coelomic Epithelium and axial organ. In the pyloric caeca, not considered as an HPT, proliferation was not detected. BrdU labelling of monolayers of cells obtained by collagenase treatment of Coelomic Epithelium, axial organ and Tiedemann body revealed induced cell proliferation in response to both LPS and ConA while proliferation of pyloric caeca and circulating coelomocytes remained sparse. By using confocal microscopy it was observed that both the morphology and functional behaviour of cells released from explants of Coelomic Epithelium showed high similarity to those of circulating phagocytes. It was concluded that the increased coelomocyte numbers observed in response to LPS and ConA were reflected in an induced cell proliferation in Coelomic Epithelium, axial organ and Tiedemann body, which reinforces the idea that these organs are HPTs and the sources of coelomocyte renewal.
A Mclaren - One of the best experts on this subject based on the ideXlab platform.
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Germ and somatic cell lineages in the developing gonad.
Molecular and cellular endocrinology, 2000Co-Authors: A MclarenAbstract:The germ cell lineage in the mouse becomes lineage-restricted about 7.2 days post coitum. Its progenitors have migrated from the proximal region of the epiblast, where they were subject to a predisposing signal from the adjacent extra-embryonic ectoderm. It appears that this and other signals determine the emergence of germ cells: unlike in some other organisms, this event is not pre-determined. After about 24 h in their initial extraembryonic location, the primordial germ cells migrate back into the embryo and make their way into the region of the developing gonad. Less is known about the origin of the various somatic cell lineages in the gonad, but some are known to derive from cells that migrate in from the mesonephros and others from the Coelomic Epithelium. Within the developing gonad, numerous interactions occur between the germ and somatic cell lineages. These are particularly important for the establishment of the spermatogenic lineage in the testis and for the differentiation of somatic tissue in the ovary. This paper will describe first the development of the germ cell lineage, up until about the time of birth, then the various somatic components of the gonad and finally the interactions that are known to occur between lineages. Unless otherwise stated, all the information refers to the mouse.
Rita Carmona - One of the best experts on this subject based on the ideXlab platform.
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conditional deletion of wt1 in the septum transversum mesenchyme causes congenital diaphragmatic hernia in mice
eLife, 2016Co-Authors: Rita Carmona, Anabel Rojas, Ana Canete, Elena Cano, Laura Ariza, Ramon MunozchapuliAbstract:Congenital diaphragmatic hernia (CDH) is a severe birth defect. Wt1-null mouse embryos develop CDH but the mechanisms regulated by WT1 are unknown. We have generated a murine model with conditional deletion of WT1 in the lateral plate mesoderm, using the G2 enhancer of the Gata4 gene as a driver. 80% of G2-Gata4Cre;Wt1fl/fl embryos developed typical Bochdalek-type CDH. We show that the posthepatic mesenchymal plate Coelomic Epithelium gives rise to a mesenchyme that populates the pleuroperitoneal folds isolating the pleural cavities before the migration of the somitic myoblasts. This process fails when Wt1 is deleted from this area. Mutant embryos show Raldh2 downregulation in the lateral mesoderm, but not in the intermediate mesoderm. The mutant phenotype was partially rescued by retinoic acid treatment of the pregnant females. Replacement of intermediate by lateral mesoderm recapitulates the evolutionary origin of the diaphragm in mammals. CDH might thus be viewed as an evolutionary atavism.
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Cells Derived from the Coelomic Epithelium Contribute to Multiple Gastrointestinal Tissues in Mouse Embryos
2016Co-Authors: Rita Carmona, Elena Cano, Andrea MattiottiAbstract:Gut mesodermal tissues originate from the splanchnopleural mesenchyme. However, the embryonic gastrointestinal Coelomic Epithelium gives rise to mesenchymal cells, whose significance and fate are little known. Our aim was to investigate the contribution of Coelomic Epithelium-derived cells to the intestinal development. We have used the transgenic mouse model mWt1/IRES/GFP-Cre (Wt1cre) crossed with the Rosa26R-EYFP reporter mouse. In the gastrointestinal duct Wt1, the Wilms ’ tumor suppressor gene, is specific and dynamically expressed in the Coelomic Epithelium. In the embryos obtained from the crossbreeding, the Wt1-expressing cell lineage produces the yellow fluorescent protein (YFP) allowing for colocalization with differentiation markers through confocal microscopy and flow cytometry. Wt1cre-YFP cells were very abundant throughout the intestine during midgestation, declining in neonates. Wt1cre-YFP cells were also transiently observed within the mucosa, being apparently released into the intestinal lumen. YFP was detected in cells contributing to intestinal vascularization (endothelium, pericytes and smooth muscle), visceral musculature (circular, longitudinal and submucosal) as well as in Cajal and Cajal-like interstitial cells. Wt1cre-YFP mesenchymal cells expressed FGF9, a critical growth factor for intestinal development, as well as PDGFRa, mainly within developing villi. Thus, a cell population derived from the Coelomic Epithelium incorporates to the gut mesenchyme and contribute to a variety of intestinal tissues, probably playing also a signaling role. Our results support the origin of interstitial cells of Cajal and viscera
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Expression of Wt1 and cytokeratins in early and middle intestinal development and early localization of Wt1cre-YFP cells.
2013Co-Authors: Rita Carmona, Elena Cano, Andrea Mattiotti, Joaquín Gaztambide, Ramón Muñoz-chápuliAbstract:A–D. Wt1 immunolocalization in consecutive sections from the same E10 embryo. Wt1 is expressed in a few cells of the Coelomic Epithelium of the foregut (FG) and in some mesenchymal cells (arrows in A and B). As shown in C and D, the expression becomes more abundant in the midgut (MG) and is weak and restricted to the Coelomic Epithelium in the hindgut (arrows in D). The Wt1-positive liver bud (LI), parietal Coelomic Epithelium (P) and intermediate mesoderm (IM) are positive controls. E–G. Wt1 immunolocalization in an E10.5 embryo. Wt1 immunoreactivity is present throughout the Coelomic Epithelium of the midgut (MG). F shows a higher magnification of the dorsal area of the midgut. Wt1 expressing Epithelium is shown by the arrows. Expression in the hindgut has increased as compared with the earlier stage shown in D (arrows in G). Developing kidneys (K) are positive controls. H–K. Wt1cre-YFP cells in consecutive sections of the same E10.5 embryo. Wt1cre-YFP cells are abundant in the foregut (FG) and anterior midgut (AMG), becoming scarcer in the posterior midgut (PMG). Abundant Wt1cre-YFP cells are present in the mesentery (MS) at this level. Ony a few cells are present in the anterior hindgut (AHG) while the posterior hindgut (PHG) lacks of Wt1cre-YFP cells. L,M. Wt1cre-YFP cells in the midgut mesenchyme of an E10.5 embryo. YFP positive and negative mesenchymal cells show a dot-like cytokeratin immunostaining by E10.5 (arrows and arrowheads, respectively in M). The endoderm is strongly cytokeratin immunoreactive. N. Cytokeratin immunostaining has disappeared from the mesenchymal cells by the stage E13.5, and it is restricted to the Coelomic Epithelium of the intestine (arrows). O–P. Wt1 immunolocalization in an E12.5 embryo. The midgut (MG) intestinal loops contained in the physiological umbilical hernia show a strong Wt1 immunoreactivity (H). However, the hindgut mesothelium is Wt1-negative by this stage (arrows in P). Note the strong Wt1 immunoreactivity of the posterior intermediate mesoderm (IM). Q–R. Wt1 immunolocalization in an E14.5 embryo. All the digestive tract mesothelium is Wt1-immunoreactive, including the small intestine (SI) and the hindgut (HG). K: kidney. Scale bars: A–G, O–R = 50 µm; H–K = 100 µm; L–N = 25 µm.
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Localization of FGF9 and PDGFRα in the developing intestine.
2013Co-Authors: Rita Carmona, Elena Cano, Andrea Mattiotti, Joaquín Gaztambide, Ramón Muñoz-chápuliAbstract:A,B. FGF9 immunoreactivity in the intestine of E15.5 embryos. Colocalization with YFP is observed in cells of the circular muscle layer as well as in Wt1cre-YFP cells within the endodermal mucosa (white arrows). Note the large FGF9+ cells, probably neural, between the circular and the longitudinal muscle layers (arrowheads). The Coelomic Epithelium is also FGF9+ (yellow arrow in B. C,D. Immunolocalization of PDGFRα in the small intestine of an E18.5 embryo. Positive mesenchymal cells are located within the developing villi (arrows in C). Colocalization of PDGFRα with YFP is shown at higher magnification in D (arrows). Scale bars A–C = 25 µm; D = 10 µm.
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Contribution of the Wt1cre-YFP cells to the visceral smooth muscle and Cajal-like interstitial cells.
2013Co-Authors: Rita Carmona, Elena Cano, Andrea Mattiotti, Joaquín Gaztambide, Ramón Muñoz-chápuliAbstract:A. Colocalization of SMCα-actin with YFP in cells ventral to the endoderm at the stage E11.5 (arrows). SMCα-actin+/Wt1cre-YFP cells can be seen in the wall of a large vessel (arrowhead). B,C. Colocalization of SMCα-actin with YFP in visceral circular muscle layer (CL) at E15.5, in transverse and longitudinal section, respectively. A submesothelial cell, positive for both markers, is shown in C by the arrowhead. Note the YFP-positive vessel wall (arrow in C). D, E. The intestinal Coelomic Epithelium is RALDH2 immunoreactive by E13.5 (D) and E15.5 (E). Note the presence of SMCα-actin immunoreactive cells, probably progenitors of the longitudinal muscle layer, lying behind the RALDH2+ mesothelium in E. F. In this neonate, colocalization of YFP with SMCα-actin is observed in the circular muscular layer (arrows). CD34+ cells are abundant in the submucosal layer, showing thin prolongations. Some of these cells are also Wt1cre-YFP (arrowheads). Note the presence of submucosal SMCα-actin cells forming the innermost muscle layer. CD34 does not colocalize with SMCα-actin. Scale bars = 25 µm.
Lanche Capel - One of the best experts on this subject based on the ideXlab platform.
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sry induces cell proliferation in the mouse gonad
Development, 2000Co-Authors: Jennife Schmahl, Eva M Eiche, Linda L Washbu, Lanche CapelAbstract:Sry is the only gene on the Y chromosome that is required for testis formation in mammals. One of the earliest morphological changes that occurs as a result of Sry expression is a size increase of the rudimentary XY gonad relative to the XX gonad. Using 5'-bromo-2'-deoxyuridine (BrdU) incorporation to label dividing cells, we found that the size increase corresponds with a dramatic increase in somatic cell proliferation in XY gonads, which is not detected in XX gonads. This male-specific proliferation was observed initially in the cells of the Coelomic Epithelium and occurred in two distinct stages. During the first stage, proliferation in the XY gonad was observed largely in SF1-positive cells and contributed to the Sertoli cell population. During the second stage, proliferation was observed in SF1-negative cells at and below the Coelomic Epithelium and did not give rise to Sertoli cells. Both stages of proliferation were dependent on Sry and independent of any other genetic differences between male and female gonads, such as X chromosome dosage or other genes on the Y chromosome. The increase in cell proliferation began less than 24 hours after the onset of Sry expression, before the establishment of male-specific gene expression patterns, and before the appearance of any other known male-specific morphological changes in the XY gonad. Therefore, an increase in cell proliferation in the male Coelomic Epithelium is the earliest identified effect of Sry expression.