Spermatogonial stem cells are quiescent, undergo self-renewal or differentiating divisions, thereby forming the cellular basis of spermatogenesis. This cellular development is orchestrated by follicle-stimulating hormone (FSH), through the production of Sertoli cell-derived factors, and by Leydig cell-released androgens. Here, we investigate the transcriptional events induced by Fsh in a steroid-independent manner on the restart of zebrafish (Danio rerio) spermatogenesis ex vivo, using testis from adult males where type A spermatogonia were enriched by estrogen treatment in vivo. Under these conditions, RNA sequencing preferentially detected differentially expressed genes in somatic/Sertoli cells. Fsh-stimulated spermatogonial proliferation was accompanied by modulating several signaling systems (i.e. Tgf-ß, Hedgehog, Wnt and Notch pathways). In silico protein-protein interaction analysis indicated a role for Hedgehog family members potentially integrating signals from different pathways during fish spermatogenesis. Moreover, Fsh had a marked impact on metabolic genes, such as lactate and fatty acid metabolism, or on Sertoli cell barrier components. Fish Leydig cells express the Fsh receptor and one of the most robust Fsh-responsive genes was insulin-like 3 (insl3), a Leydig cell-derived growth factor. Follow-up work showed that recombinant zebrafish Insl3 mediated pro-differentiation effects of Fsh on spermatogonia in an androgen-independent manner. Our experimental approach allowed focusing on testicular somatic genes in zebrafish and showed that the activity of signaling systems known to be relevant in stem cell systems was modulated by Fsh, providing promising leads for future work, as exemplified by the studies on Insl3. Overall design: 12 samples in total were analyzed: 6 biological replicates from control testis samples and 6 biological replicates from Fsh-treated testis samples (all co-incubated with trilostane).
Expression profiling identifies Sertoli and Leydig cell genes as Fsh targets in adult zebrafish testis.
No sample metadata fields
View SamplesAfter an acclimatization period with increasing temperature (from 27 to 35째C; ~1째C increment/day), adult zebrafish males were exposed to 35째C for 14 days and injected with the cytostatic agent busulfan (single intraperitoneal injection after 7 days at 35째C; 40 mg/Kg). Then, fish were placed back to normal water temperature and testis samples collected at different time points. Morphological analysis of testicular samples showed maximum germ cell depletion 10 days post busulfan injection (i.e. 10 dpi) and the recovery of endogenous spermatogenesis ~14 dpi. Total RNA was isolated from (1) testes of untreated adult control zebrafish, (2) germ cell-depleted, and (3) testis tissue at the beginning of the recovery period, and selected samples were used for library preparation Overall design: 15 samples in total were analyzed: 5 biological replicates from control testis samples, 5 biological replicates from depleted testis samples and 5 biological replicates from recovering testis samples
Endocrine and local signaling interact to regulate spermatogenesis in zebrafish: follicle-stimulating hormone, retinoic acid and androgens.
Specimen part, Subject
View SamplesFsh-mediated regulation of zebrafish spermatogenesis includes modulating the expression of testicular growth factors. Here, we study if and how two Sertoli cell-derived Fsh-responsive growth factors, anti-Müllerian hormone (Amh; inhibiting steroidogenesis and germ cell differentiation) and insulin-like growth factor 3 (Igf3; stimulating germ cell differentiation), cooperate in regulating spermatogonial development. In dose response and time course experiments with primary testis tissue cultures, Fsh upregulated igf3 transcript levels and down-regulated amh transcript levels; igf3 transcript levels were more rapidly up-regulated and responded to lower Fsh concentrations than were required to decrease amh mRNA levels. Quantification of immunoreactive Amh and Igf3 on testis sections showed that Fsh increased slightly Igf3 staining but decreased clearly Amh staining. Studying the direct interaction of the two growth factors showed that Amh compromised Igf3-stimulated proliferation of type A (both undifferentiated [Aund] and differentiating [Adiff]) spermatogonia. Also the proliferation of those Sertoli cells associated with Aund spermatogonia was reduced by Amh. To gain more insight into how Amh inhibits germ cell development, we examined Amh-induced changes in testicular gene expression by RNA sequencing. The majority (69%) of the differentially expressed genes was down-regulated by Amh, including several stimulators of spermatogenesis, such as igf3 and steroidogenesis-related genes. At the same time, Amh increased the expression of inhibitory signals, such as inha and id3, or facilitated prostaglandin E2 (PGE2) signaling. Evaluating one of the potentially inhibitory signals, we indeed found in tissue culture experiments that PGE2 promoted the accumulation of Aund at the expense of Adiff and B spermatogonia. Our data suggest that an important aspect of Fsh bioactivity in stimulating spermatogenesis is implemented by restricting the different inhibitory effects of Amh and by counterbalancing them with stimulatory signals, such as Igf3 Overall design: 10 samples in total were analyzed: 5 biological replicates from control testis samples and 5 biological replicates from Amh-treated testis samples (all co-incubated with 11KT)
Antagonistic regulation of spermatogonial differentiation in zebrafish (Danio rerio) by Igf3 and Amh.
No sample metadata fields
View SamplesIdentification of genetic/cytogenetic alterations and differentially expressed cellular genes in HPV16 E6, E7 and E6/E7 positive human foreskin keratinocytes
Complementation of non-tumorigenicity of HPV18-positive cervical carcinoma cells involves differential mRNA expression of cellular genes including potential tumor suppressor genes on chromosome 11q13.
No sample metadata fields
View SamplesIdentification of genes differentially expressed in tumorigenic compared to non-tumorigenic, HPV18 positive cells
Complementation of non-tumorigenicity of HPV18-positive cervical carcinoma cells involves differential mRNA expression of cellular genes including potential tumor suppressor genes on chromosome 11q13.
No sample metadata fields
View SamplesColon cancer is a major cause of cancer deaths in Western countries and is associated with diets high in red meat. Heme, the iron-porphyrin pigment of red meat, induces cytotoxicity of gut contents which injures surface cells leading to compensatory hyperproliferation of crypt cells. This hyperproliferation results in epithelial hyperplasia which increases the risk of colon cancer. In humans, a high red-meat diet increases Bacteroides spp in feces. Therefore, we simultaneously investigated the effects of dietary heme on colonic microbiota and on the host mucosa of mice. Whole genome microarrays showed that heme injured the colonic surface epithelium and induced hyperproliferation by changing the surface to crypt signaling. Using 16S rRNA phylogenetic microarrays, we investigated whether bacteria play a role in this changed signaling. Heme increased Bacteroidetes and decreased Firmicutes in colonic contents. This shift was most likely caused by a selective susceptibility of Gram-positive bacteria to heme cytotoxic fecal water, which is not observed for Gram-negative bacteria, allowing expansion of the Gram-negative community. The increased amount of Gram-negative bacteria most probably increased LPS exposure to colonocytes, however, there is no appreciable immune response detected in the heme-fed mice. There was no functional change in the sensing of the bacteria by the mucosa, as changes in inflammation pathways and Toll- like receptor signaling were not detected. This unaltered host-microbe cross-talk indicates that the changes in microbiota did not play a causal role in the observed hyperproliferation and hyperplasia.
Dietary heme alters microbiota and mucosa of mouse colon without functional changes in host-microbe cross-talk.
Sex, Age, Specimen part
View SamplesPreviously, we showed that dietary heme injured the colonic surface epithelium and induced hyperproliferation by changing the surface to crypt signaling. In this study we investigated whether bacteria play a role in this changed signaling. Dietary heme increased the Bacteroidetes and decreased the Firmicutes in colonic content. This shift was caused by a selective susceptibility of Gram-positive bacteria to the heme cytotoxic fecal waters, which is not observed for Gram-negative bacteria allowing expansion of the Gram-negative community. The increased amount of Gram-negative bacteria increased LPS exposure to colonocytes, however, there is no appreciable immune response detected in the heme-fed mice. There were no signs of sensing of the bacteria by the mucosa, as changes in TLR signaling were not present. This lack of microbe-host cross talk indicated that the changes in microbiota do not play a causal role in the heme-induced hyperproliferation.
Dietary heme alters microbiota and mucosa of mouse colon without functional changes in host-microbe cross-talk.
Sex, Age, Specimen part, Treatment
View SamplesExpression data from mouse tumor-specific CD4+ T cells
Molecular profiling of tumor-specific T<sub>H</sub>1 cells activated in vivo.
Specimen part
View SamplesThe immune system can both promote and suppress cancer. Chronic inflammation and proinflammatory cytokines such as interleukin (IL)-1 and IL-6 are considered tumor-promoting. In contrast, the exact nature of protective antitumor immunity remains obscure. In this study, we have quantified locally secreted cytokines during primary immune responses against myeloma and B-cell lymphoma in mice. Strikingly, successful cancer immunosurveillance mediated by tumor-specific CD4+ T cells was consistently associated with elevated local levels of both proinflammatory (IL-1aplha, IL-1beta, and IL-6) and T helper 1 (Th1)-associated cytokines (interferon-alpha, IL-2, IL-12). Cancer eradication was achieved by a collaboration between tumor-specific Th1 cells and tumor-infiltrating, antigen-presenting macrophages. Th1 cells induced secretion of IL-1? and IL-6 by macrophages. Th1-derived interferon-? was shown to render macrophages directly cytotoxic to cancer cells, and to induce macrophages to secrete the angiostatic chemokines CXCL9/MIG and CXCL10/IP-10. Thus, inflammation, when driven by tumor-specific Th1 cells, may prevent rather than promote cancer.
Inflammation driven by tumour-specific Th1 cells protects against B-cell cancer.
Specimen part
View Samplesaffy_popsec_nancy_roots_poplar - This project aims to identify genes of interest for water deficit acclimation and/or adaptation in a tree species: poplar. We look for genes and gene expression networks related to drought stress. We intend to analyse the transcriptome in root apices, in two genotypes, Carpaccio and Soligo, at various stages and intensities of stress. Root apex is the location of root elongation and these analyses intend to identify genes involved in the control of cell expansion and thus of root elongation. Indeed, root growth maintenance in response to water shortage contributes to plant tolerance to water deficit. The comparison between medium and severe stress intensities and between early and long term stresses will power the selection of genes of interest. The co-analysis of two genotypes of contrasted tolerance to water deficit should help to better discriminate genes presenting a potential adaptative character from genes responding passively to the constraint.-Two poplar clones, Soligo (S) and Carpacio (C) were submitted to 4 treatments: control, mild water deficit, moderate water deficit (12-day long for both) and early-drought stress (about 36-h long). Growth and physiology was characterised on a batch of plants and samples collected on another batch of plants. Four to eight root apices (1cm-long) were collected on each individual tree. Total RNAs were extracted from all roots for each tree individually. Two pools of 3 (or 2) individuals were made using equimolar ratio. A pool is considered as one biological replicate and corresponds to one Affymetrix slide. The two biological replicates originate from the same experiment.
Comparative transcriptomics of drought responses in Populus: a meta-analysis of genome-wide expression profiling in mature leaves and root apices across two genotypes.
Specimen part
View Samples