Primitive erythropoiesis in the mouse yolk sac is followed by definitive erythropoiesis resulting in adult erythrocytes. In comparison to definitive erythropoiesis little is known about the genes that control the embryonic erythroid program. The purpose of this study was to generate a profile of mouse embryonic yolk sac erythroid cells and identify novel regulatory genes differentially expressed in erythroid compared to non-erythroid (epithelial cells).
Identification of erythroid-enriched gene expression in the mouse embryonic yolk sac using microdissected cells.
No sample metadata fields
View SamplesRNAseq analysis of caecal tissue from 14 C. jejuni-susceptible and 14 C. jejuni-resistant birds from a single population of infected chickens was conducted in order to identify gene expression associated with resistance to colonization. Significantly higher expression of genes involved in the innate immune response, cytokine signaling, B cell and T cell activation and immunoglobulin production, as well as the renin-angiotensin system was observed in resistant birds. Overall design: A population of 255 Barred Rock chickens were orally inoculated with C. jejuni and their caecal colonization levels estimated 48 hours post-inoculation. Caecal samples from 14 birds with no colonization and the 14 birds with the highest colonization were selected for mRNA sequencing.
Genome-wide association analysis of avian resistance to Campylobacter jejuni colonization identifies risk locus spanning the CDH13 gene.
Specimen part, Subject
View SamplesTranscriptomic analysis of gene expression during the differentiation of cell suspension cultures into tracheary elements using the biological system published by Pesquet et al., Current Biology (2010): tracheary element differentiation was triggered by externally supplying hormone-free habituated cell suspension cultures of Arabidopsis thaliana Col-0 with auxin, cytokinin and epibrassinolides; RNA samples extracted from 3 independent time-courses every 12h from 0h to 4 days were analyzed using ATH1 Arabidopsis Affymetrix micro-array
Proteomic Analysis of Microtubule Interacting Proteins over the Course of Xylem Tracheary Element Formation in Arabidopsis.
Specimen part, Time
View SamplesPURPOSE: Previous mouse studies using corn oil (-6) as the dietary fat source suggest that decreasing dietary fat content can slow prostate cancer (PCa) growth. However, other studies, in which the diet was composed around saturated fat, showed no difference in outcomes between high-fat and low-fat diets. The relative effects of other fats, such as fish oil and olive oil, also remain unexplored. To our knowledge, no trial has yet compared the effect of various fats on prostate cancer progression. Therefore, we sought to systematically study the effect of fish oil, olive oil, corn oil, and saturated fat on prostate cancer progression. METHODS: A total of 96 male SCID mice were injected with LAPC-4 human PCa cells. Two weeks following injection, mice were singly-housed and randomized to either a fish oil, olive oil, corn oil, or saturated fat based diet. Animals were euthanized when tumors reached 1,000 mm3. Serum was collected at sacrifice and assayed for PSA, insulin, IGF-1, IGFBP-3, and PGE-2 levels. Tumors were also assayed for PGE-2, and COX-2 levels, and gene array analysis was performed. RESULTS: Mice weights and tumor volumes were equivalent across groups at randomization. Overall, fish-oil consumption was associated with improved survival, relative to all other dietary groups (Log-rank, all p<0.05). We did not detect any significant difference in serum PSA, insulin, IGF-1, IGFBP-3, and PGE-2 levels. Glucose at the time of sacrifice was statistically different between groups, with the fish-oil fed mice having the highest levels of serum glucose (Kruskal-Wallis, p=0.03).
Fish oil slows prostate cancer xenograft growth relative to other dietary fats and is associated with decreased mitochondrial and insulin pathway gene expression.
Specimen part
View SamplesComparison of the changes in mitochondrial gene expression of cells in which extracellular growth factors and/or mitogens have been added.
Extracellular growth factors and mitogens cooperate to drive mitochondrial biogenesis.
Specimen part
View SamplesWe identify genes presenting a specific expression profile in midgut carcinoid cells, primary carcinoids tumors and liver metastasis were gene profiled.
Novel markers for enterochromaffin cells and gastrointestinal neuroendocrine carcinomas.
Specimen part
View SamplesEndosperm is an absorptive structure that supports embryo development or seedling germination in angiosperms. The endosperm of cereals is a main source of food, feed, and industrial raw materials worldwide. However, the gene regulatory networks that control endosperm cell differentiation remain largely unclear. As a first step toward characterizing these networks, we profiled the mRNAs in five major cell types of the differentiating endosperm and in the embryo and four maternal compartments of the kernel. Comparisons of these mRNA populations revealed the diverged gene expression programs between filial and maternal compartments, and an unexpected close correlation between embryo and the aleurone layer of endosperm. Gene co-expression network analysis identified co-expression modules associated with single or multiple kernel compartments including modules for the endosperm cell types, some of which showed enrichment of previously identified temporally activated and/or imprinted genes. Detailed analyses of a co-expression module highly correlated with the basal endosperm transfer layer (BETL) identified a regulatory module activated by MRP-1, a regulator of BETL differentiation and function. These results provide a high-resolution atlas of gene activity in the compartments of the maize kernel and help to uncover the regulatory modules associated with the differentiation of the major endosperm cell types. Overall design: RNAs from ten compartments of the maize kernel including the central starchy endosperm (CSE), conducting zone (CZ), aleurone (AL), basal endosperm transfer layer (BETL), embryo-surrounding region (ESR), nucellus (NU), pericarp (PE), placenta-chalazal region (PC), the vascular region of the pedicel (PED), and the embryo (EMB) were isolated at 8 days after pollination (DAP) using laser-capture microdissection and sequenced using an Illumina HiSeq 2000 platform.
RNA sequencing of laser-capture microdissected compartments of the maize kernel identifies regulatory modules associated with endosperm cell differentiation.
Age, Specimen part, Cell line, Subject
View SamplesThe Krppel-like factors, KLF1 and KLF2, positively regulate embryonic -globin expression, and have additional overlapping roles in embryonic (primitive) erythropoiesis. KLF1-/-KLF2-/- double knockout mice are anemic at embryonic day 10.5 (E10.5) and die by E11.5, in contrast to single knockouts. To investigate the combined roles of KLF1 and KLF2 in primitive erythropoiesis, expression profiling of E9.5 erythroid cells was performed. A limited number of genes had a significantly decreasing trend of expression in wild-type, KLF1-/- and KLF1-/-KLF2-/-. Among these, c-myc emerged as a central node in the most significant gene network. c-myc expression is synergistically regulated by KLF1 and KLF2, and both factors bind the c-myc promoters. To characterize the role of c-myc in primitive erythropoiesis, ablation was performed specifically in mouse embryonic proerythroblast cells. After E9.5, these embryos exhibit an arrest in the normal expansion of circulating red cells and develop anemia analogous to KLF1-/-KLF2-/-. In the absence of c-myc, circulating erythroid cells do not show the normal increase in - and -like globin expression, but interestingly, have accelerated erythroid maturation, between E9.5 and E11.5. This study reveals a novel regulatory network by which KLF1 and KLF2 regulate c-myc, to control the primitive erythropoietic program.
Kruppel-like factor 1 (KLF1), KLF2, and Myc control a regulatory network essential for embryonic erythropoiesis.
Specimen part
View SamplesMouse embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) exhibit a pluripotent developmental potential, contributing to all embryonic cell types, though rarely to extra-embryonic lineages. Unexpectedly, rare, totipotent-like stem cells have been identified in cultured ESC populations, suggesting the existence of a discrete molecular pathway that regulates the transition between totipotency and pluripotency in vitro. Here, we identify a single miRNA, miR-34a, whose deficiency in mouse pluripotent stem cells expands cell fate potential, giving rise to both embryonic and extra-embryonic lineages in vitro and in vivo. The expression profiles of the totipotent-like miR-34a-knockout murine pluripotent stem cells are characterized by a strong induction of MERVL endogenous retroviruses, a key molecular hallmark shared with totipotent mouse 2-cell blastomeres and totipotent-like mouse ESCs. In all three cell types, a subset of MERVL elements promotes the expression of specific isoforms of the proximal protein-coding genes. We demonstrate that miR-34a represses MERVL expression through transcriptional regulation, at least in part, by directly targeting the transcription factor GATA-binding protein 2 (Gata2). Since MERVL activation correlated precisely with the totipotent-like state, we hypothesized that the miR-34a/Gata2 pathway that regulates MERVL expression in ESCs/iPSCs also regulates the acquisition of totipotency in culture. Consistent with this hypothesis, gata2 knock-down in miR-34a-knockout mouse pluripotent stem cells not only reduced MERVL expression, but also abolished the expanded cell fate potential of these cells both in vitro and in vivo. Taken together, our findings not only provide key insights into the functional importance of miR-34a in restricting the totipotent cell fate potential of pluripotent stem cells, but also elucidate the underlying molecular basis by which miR-34a regulates the developmental potentials of ESCs/iPSCs. Overall design: Wildtype and miR-34a-deficient iPSCs, three biological replicates per group
Deficiency of microRNA <i>miR-34a</i> expands cell fate potential in pluripotent stem cells.
No sample metadata fields
View SamplesPrion diseases are fatal neurodegenerative disorders that include bovine spongiform encephalopathy (BSE) and scrapie in animals and Creutzfeldt-Jakob disease (CJD) in humans. They are characterized by long incubation periods, variation in which is determined by many factors including genetic background. In some cases it is possible that incubation time may be directly correlated to the level of gene expression. In order to test this hypothesis we combined incubation time data from five different inbred lines of mice with quantitative gene expression profiling in normal brains and identified five genes with expression levels that correlate with incubation time. One of these genes, Hspa13 (Stch), is a member of the Hsp70 family of ATPase heat shock proteins which have been previously implicated in prion propagation. To test whether Hspa13 plays a causal role in determining the incubation period we tested two over-expressing mouse models. The Tc1 human chromosome 21 (Hsa21) transchromosomic mouse model of Down syndrome is trisomic for many Hsa21 genes including Hspa13 and following Chandler/RML prion inoculation shows a 4% reduction in incubation time. Furthermore, a transgenic model with eight fold over-expression of mouse Hspa13 exhibited highly significant reductions in incubation time of 16%, 15% and 7% following infection with Chandler/RML, ME7 and MRC2 prion strains respectively. These data further implicate Hsp70-like molecular chaperones in protein misfolding disorders such as prion disease.
Overexpression of the Hspa13 (Stch) gene reduces prion disease incubation time in mice.
Specimen part
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