Cumulus cells and mural granulosa cells (MGCs) are spatially and functionally distinct cell types in antral follicles: cumulus cells contact the oocyte and most MGCs contact the basal lamina. For transcriptomic analyses, both cell types were collected from small and large antral follicles, before and after stimulation of immature mice with eCG, respectively. Both cell types underwent dramatic transcriptomic changes and the differences between them became greater with follicular growth. Although cumulus cells of both stages of follicular development are competent to undergo expansion in vitro, they were otherwise remarkably dissimilar with transcriptomic changes quantitatively equivalent to those of MGCs. Gene Ontology (GO) analysis showed that cumulus cells of small follicles were enriched in transcripts generally associated with catalytic components of metabolic processes while those from large follicles were involved in regulation of metabolism, cell differentiation, and adhesion. Upon contrasting cumulus cells versus MGCs, cumulus cells were enriched in transcripts associated with metabolism and cell proliferation while MGCs were enriched for transcripts involved in cell signaling and differentiation.
Transcriptomic diversification of developing cumulus and mural granulosa cells in mouse ovarian follicles.
Specimen part
View SamplesOocyte-derived paracrine factors and estrogens cooperate to regulate the function and development of mouse cumulus cells.
Cooperative effects of 17β-estradiol and oocyte-derived paracrine factors on the transcriptome of mouse cumulus cells.
Sex, Specimen part, Treatment
View SamplesThere is massive destruction of transcripts during maturation of mouse oocytes. The objective of this project was to identify and characterize the transcripts that are degraded versus those that are stable during the transcriptionally silent germinal vesicle (GV)-stage to metaphase II (MII)-stage transition using the microarray approach. A system for oocyte transcript amplification using both internal and 3-poly(A) priming was utilized to minimize the impact of complex variations in transcript polyadenylation prevalent during this transition. Transcripts were identified and quantified using Affymetrix Mouse Genome 430 v2.0 GeneChip. The significantly changed and stable transcripts were analyzed using Ingenuity Pathways Analysis and GenMAPP/MAPPFinder to characterize the biological themes underlying global changes in oocyte transcripts during maturation. It was concluded that the destruction of transcripts during the GV to MII transition is a selective rather than promiscuous process in mouse oocytes. In general, transcripts involved in processes that are associated with meiotic arrest at the GV-stage and the progression of oocyte maturation, such as oxidative phosphorylation, energy production, and protein synthesis and metabolism, were dramatically degraded. In contrast, transcripts encoding participants in signaling pathways essential for maintaining the unique characteristics of the MII-arrested oocyte, such as those involved in protein kinase pathways, were the most prominent among those stables.
Selective degradation of transcripts during meiotic maturation of mouse oocytes.
No sample metadata fields
View SamplesMouse oocytes control cumulus cell metabolic processes that are deficient in the oocytes themselves and this delegation is necessary for oocyte development. Oocyte-derived bone morphogenetic factor 15 (BMP15) and growth differentiation factor 9 (GDF9) appear to be key regulators of follicular development. The effect of these factors on cumulus cell function before the preovulatory surge of luteinizing hormone (LH) was assessed by analysis of the transcriptomes of cumulus cells from wildtype (WT), Bmp15-/-, and Bmp15-/- Gdf9+/- double mutant (DM) mice using microarray analysis. The biological themes associated with the most highly-affected transcripts were identified using bioinformatic approaches, IPA and GenMAPP/MAPPFinder. There were 5,332, 7,640, and 2,651 transcripts identified to be significantly changed in the comparisons of Bmp15-/- vs. WT, DM vs. WT, and DM vs. Bmp15-/- respectively by the criteria of FC (fold change) p <0.01. Among theses changed transcripts, 744 were commonly changed in all three pair-wise comparisons, and hence were considered to be the most highly affected transcripts by mutation of Bmp15 and Gdf9. IPA Analyses revealed that metabolism was the major theme associated with the most highly-changed transcripts: glycolysis and sterol biosynthesis were the two most significantly affected pathways. Most of the transcripts encoding enzymes for sterol biosynthesis were down-regulated in both mutant cumulus cells and in WT cumulus cell after oocytectomy. Similarly, there was a reduction of de novo-synthesized cholesterol in these cumulus cells. This suggests that oocytes regulate cumulus cell metabolism, particularly sterol biosynthesis, by promoting the expression of corresponding transcripts. Furthermore, in WT-mice, Mvk, Pmvk, Fdps, Sqle, Cyp51, Sc4mol, and Ebp, which encode enzymes in the sterol biosynthetic pathway, were found to be expressed robustly in cumulus cells, but expression was barely detectable in oocytes. Levels of de novo-synthesized cholesterol were significantly higher in cumulusenclosed oocytes than denuded oocytes. These results indicate that mouse oocytes are deficient in their ability to synthesize cholesterol and require cumulus cells to provide them with products of the sterol biosynthetic pathway. Oocyte-derived BMP15 and GDF9 may promote this metabolic pathway in cumulus cells as compensation for their own deficiencies.
Oocyte regulation of metabolic cooperativity between mouse cumulus cells and oocytes: BMP15 and GDF9 control cholesterol biosynthesis in cumulus cells.
No sample metadata fields
View SamplesMarf1 (MUT) female mice are infertile and the meiosis of the oocytes are arrest at prophase I. We thought to identify the potential causes of the meiotic arrest phenotype in the mutant oocytes by comparing the transcriptomes of the WT and mutant fully-grown oocytes (from 23-d old mice) that are transcriptional silent.
MARF1 regulates essential oogenic processes in mice.
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View SamplesRepro9 in an allele of Mybl1 (A-Myb) transcription factor obtained in ENU screen to identify alleles causing mouse infertility. Repro9/repro9 mutant males are infertile due to meiotic arrest at pachytene stage. Mutants show wide range of abnormalities including inefficient chromosome synapsis, sex body formation and progression through meiotic cycle. Females are unaffected. To determine genes transcriptionally regulated by MYBL1 we analyzed gene expression profiles of wild type and repro9/repro9 mutant testis at 14 and 17 days postpartum. Analysis revealed many misregulated genes, in majority downregulated, at day 14 pp and even more at day 17 pp, probably due to secondary effects of meiotic arrest. Significantly misregulated genes were characterized by Gene Ontology. Comparative gene expression analysis uncovered potential targets of MYBL1 regulation that play roles in regulation of transcription, cell cycle, apoptosis, protein phosphorylation and ubiquitination, chromosome organization and others.
A-MYB (MYBL1) transcription factor is a master regulator of male meiosis.
Specimen part
View SamplesWe sought to identify genes that are regulated by the ovulatory signals in mouse cumulus cells.
Oocyte-dependent activation of MTOR in cumulus cells controls the development and survival of cumulus-oocyte complexes.
No sample metadata fields
View SamplesWe sought to identify the potential specific roles of the MTOR signalling in cumulus cells by comparing the transcriptomes of the Control (treated with the DMSO vehicle) and MTOR-specific inhibitor Torin 1(5uM)-treated cumulus-oocyte complexes that were cultured for 16 hours.
Oocyte-dependent activation of MTOR in cumulus cells controls the development and survival of cumulus-oocyte complexes.
Specimen part, Treatment
View SamplesGene regulatory networks that govern hematopoietic stem cells (HSC) and leukemiainitiating cells (L-IC) are deeply entangled. Thus, the discovery of compounds that target L-IC while sparing HSC is an attractive but difficult endeavor. Presently, most drug discovery approaches fail to counter-screen compounds against normal hematopoietic stem/progenitor cells (HSPC) to assess therapeutic index. Here, we present a combined in vitro and in vivo strategy to identify compounds specific to L-IC in acute myeloid leukemia (AML). A high-throughput screen of 4000 compounds on novel leukemia cell lines derived from human experimental leukemogenesis models yielded 80 hits, of which most were toxic to normal HSPC. Of the 10 compounds that passed this initial filter, we chose to characterize a single compound, kinetic riboside (KR), on AML L-IC and HSPC. KR demonstrated comparable efficacy to standard therapies against 63 primary AMLs. In vitro, KR effectively targeted the L-IC-enriched CD34+CD38- AML fraction, while sparing normal HSPC enriched fractions, although these effects were mitigated on HSC assayed in vivo, and highlights the importance of in vivo L-IC and HSC assays to measure function. Overall, we provide a novel approach to screen large drug libraries for the discovery of anti-L-IC compounds for human leukemias.
A small molecule screening strategy with validation on human leukemia stem cells uncovers the therapeutic efficacy of kinetin riboside.
Cell line, Treatment
View SamplesWe have identified ZNF423 (also known as Ebfaz, OAZ or Zfp423) as a component critically required for retinoic acid (RA)-induced differentiation. ZNF423 associates with the RAR/RXR nuclear receptor complex and is essential for transactivation in response to retinoids. Down-regulation of ZNF423 expression by RNA interference in neuroblastoma cells results in a growth advantage and resistance to RA-induced differentiation, whereas overexpression of ZNF423 leads to growth inhibition and enhanced differentiation. Futhermore, we show that low ZNF423 expression is associated with poor disease outcome of neuroblastoma patients. To identify the other key pathways regulated by ZNF423 in human neuroblastoma, we expressed elevated levels of ZNF423 in SH-SY5Y cells and performed full genome gene expression analysis in these cells.
ZNF423 is critically required for retinoic acid-induced differentiation and is a marker of neuroblastoma outcome.
Specimen part
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