The eukaryotic genome is organized in a three-dimensional structure called chromatin, constituted by DNA and associated proteins, the majority of which are histones. Post-translational modifications of histone proteins greatly influence chromatin structure and regulate many DNA-based biological processes. Methylation of lysine 36 of histone 3 (H3K36) is a post-translational modification functionally relevant during early steps of DNA damage repair. Here, we show that the JMJD-5 regulates H3K36 di-methylation and it is required at late stages of double strand break repair mediated by homologous recombination. Loss of jmjd-5 results in hypersensitivity to ionizing radiation and in meiotic defects, and it is associated with aberrant retention of RAD-51 at sites of double strand breaks. Analyses of jmjd-5 genetic interactions with genes required for resolving recombination intermediates (rtel-1) or promoting the resolution of RAD-51 double stranded DNA filaments (rfs-1 and helq-1) suggest that jmjd-5 prevents the formation of stalled postsynaptic recombination intermediates and favors RAD-51 removal. As these phenotypes are all recapitulated by a catalytically inactive jmjd-5 mutant, we propose a novel role for H3K36me2 regulation during late steps of homologous recombination critical to preserve genome integrity. Overall design: RNA sequencing of N2 and jmjd-5(tm3735) at 20C and 25C at generation 1 (G1) and generation 6 (G6)
JMJD-5/KDM8 regulates H3K36me2 and is required for late steps of homologous recombination and genome integrity.
Subject
View SamplesTranscriptome analysis of a population of control animals vs cisplatin-treated, in duplicate Overall design: A mixed population of worms representing all stages and growing under control conditions was exposed to 60 µg/ml of cisplatin for 24 hours at 20ºC. Treated and control samples weer collected in biological replicates.
Genetic and cellular sensitivity of <i>Caenorhabditis elegans</i> to the chemotherapeutic agent cisplatin.
Cell line, Treatment, Subject
View SamplesDisrupted differentiation is a hallmark of numerous diseases, which in epidermis alone impact >25% of the population. In a search for dominant mediators of differentiation, we defined a requirement for the ZNF750 nuclear protein in terminal epidermal differentiation. ZNF750 controlled genes mutated in numerous human skin diseases, including FLG, LOR, LCE3B, ALOXE3, and SPINK5. ZNF750 potently induced progenitor differentiation via an evolutionarily conserved C2H2 zinc finger motif. The epidermal master regulator, p63, bound the ZNF750 promoter and was necessary for its induction. ZNF750 restored differentiation to p63-deficient tissue, suggesting it acts downstream of p63. A search for functionally important ZNF750 targets via analysis of ZNF750-regulated genes identified KLF4, a transcription factor that activates late epidermal differentiation genes. ZNF750 binds the Klf4 promoter and controls its expression. ZNF750 thus provides a direct link between a tissue-specifying factor, p63, and an effector of terminal differentiation, Klf4, and represents a potential future target for disorders of this process.
ZNF750 is a p63 target gene that induces KLF4 to drive terminal epidermal differentiation.
Specimen part, Treatment
View SamplesBackground: The diverse immunomodulatory effects of vitamin D are increasingly being recognized. However, the ability of oral vitamin D to modulate immune responses in vivo has not been established in humans. Methods: Twenty healthy adults were randomized to receive placebo or a single high dose of vitamin D3 (cholecalciferol) one hour after localized skin irradiation with an erythemogenic dose of ultraviolet radiation. Primary outcomes included skin redness, skin thickness, and tissue expression of inflammatory mediators (TNF- and iNOS). Secondary outcomes included microarray analyses. Results: As compared to placebo, subjects receiving vitamin D3 (200,000 IU) demonstrated reduced expression of TNF- (p=0.04) and iNOS (p=0.02) in skin biopsies 48 hours after ultraviolet light exposure. Demonstrated trends included reduced skin redness (p=0.17), and reduced skin thickness (p=0.09) in subjects receiving vitamin D3 (200,000 IU). Unsupervised clustering of individuals based on global gene expression revealed that subjects with enhanced skin barrier repair expression profiles had higher serum vitamin D3 levels (p=0.007), increased arginase expression (p=0.005), and a sustained reduction in skin redness (p=0.02) after treatment, as compared to subjects with enhanced inflammatory gene expression profiles.
Oral Vitamin D Rapidly Attenuates Inflammation from Sunburn: An Interventional Study.
Sex, Age, Specimen part, Race
View SamplesA comparison of gene expression in the mammary gland of lactating mice at day 9 after parturition between Akt -/- and wildtype individuals.
Isoform-specific requirement for Akt1 in the developmental regulation of cellular metabolism during lactation.
Sex, Age, Specimen part, Subject
View SamplesWe performed mRNA transcriptional profiling on Drosophila S3 cells after 4 hours treatment with novel lipid storage inhibitors belonging to three different chemotypes. Overall design: Profiling of RNA expression after treatment with three pairs of active/inactive compounds or DMSO as a control in triplicates and without treatment in the presence/absence of oleic acid in sextuplicate.
A Class of Diacylglycerol Acyltransferase 1 Inhibitors Identified by a Combination of Phenotypic High-throughput Screening, Genomics, and Genetics.
Cell line, Subject, Compound
View SamplesMultiple sclerosis involves an aberrant autoimmune response and progressive failure of remyelination in the central nervous system. Prevention of neural degeneration and subsequent disability requires remyelination through the generation of new oligodendrocytes, but current treatments exclusively target the immune system. Oligodendrocyte progenitor cells are stem cells in the central nervous system and the principal source of myelinating oligodendrocytes. These cells are abundant in demyelinated regions of patients with multiple sclerosis, yet fail to differentiate, thereby representing a cellular target for pharmacological intervention. To discover therapeutic compounds for enhancing myelination from endogenous oligodendrocyte progenitor cells, we screened a library of bioactive small molecules on mouse pluripotent epiblast stem-cell-derived oligodendrocyte progenitor cells. Here we show seven drugs function at nanomolar doses selectively to enhance the generation of mature oligodendrocytes from progenitor cells in vitro. Two drugs, miconazole and clobetasol, are effective in promoting precocious myelination in organotypic cerebellar slice cultures, and in vivo in early postnatal mouse pups. Systemic delivery of each of the two drugs significantly increases the number of new oligodendrocytes and enhances remyelination in a lysolecithin-induced mouse model of focal demyelination. Administering each of the two drugs at the peak of disease in an experimental autoimmune encephalomyelitis mouse model of chronic progressive multiple sclerosis results in striking reversal of disease severity. Immune response assays show that miconazole functions directly as a remyelinating drug with no effect on the immune system, whereas clobetasol is a potent immunosuppressant as well as a remyelinating agent. Mechanistic studies show that miconazole and clobetasol function in oligodendrocyte progenitor cells through mitogen-activated protein kinase and glucocorticoid receptor signalling, respectively. Furthermore, both drugs enhance the generation of human oligodendrocytes from human oligodendrocyte progenitor cells in vitro. Collectively, our results provide a rationale for testing miconazole and clobetasol, or structurally modified derivatives, to enhance remyelination in patients. Overall design: RNA sequencing of oligodendrocyte progenitor cells treated with vehicle, miconazole or clobetasol for 0, 2, 6, or 12 hours. Cells were plated 1.5 hours prior to addition of drug.
Drug-based modulation of endogenous stem cells promotes functional remyelination in vivo.
No sample metadata fields
View SamplesTetraploidization, or genome doubling, is a prominent event in tumorigenesis, primarily because cell division in polyploid cells is error-prone and produces aneuploid cells. This study investigates changes in gene expression evoked in acute and adapted tetraploid cells and their impact on cell-cycle progression. Acute polyploidy was generated by knockdown of essential regulator of cytokinesis Anillin, which resulted in cytokinesis failure and formation of binucleate cells, or by chemical inhibition of Aurora kinases, causing abnormal mitotic exit with formation of single cells with aberrant nuclear morphology. Transcriptome analysis of these acute tetraploid cells revealed common signatures of activation of the tumor-suppressor protein p53. Suppression of proliferation in these cells was dependent on p53 and its transcriptional target - Cdk inhibitor p21. Rare proliferating tetraploid cells can emerge from acute polyploid populations. Gene expression analysis of single-cell derived, adapted tetraploid clones showed upregulation of several p53 target genes and cyclin D2, the activator of Cdk4/6/2. Overexpression of cyclin D2 in diploid cells strongly potentiated the ability to proliferate with increased DNA content despite the presence of functional p53. These results point out that p53-mediated suppression of proliferation of polyploid cells can be averted by increased levels of oncogenes such as Cyclin D2, elucidating a possible route for tetraploidy-mediated genomic instability in carcinogenesis. Overall design: Three biological replicates of cells treated with siRNA against Anillin or a non-targeting control are FACS sorted into 2N or 4N populations and assessed for gene expression differences via RNA Seq for a total of 12 samples.
Transcriptome analysis of tetraploid cells identifies cyclin D2 as a facilitator of adaptation to genome doubling in the presence of p53.
Cell line, Subject
View SamplesCommercial brewing yeast strains are exposed to a number of potential stresses including oxidative stress. The aim of this investigation was to measure the physiological and transcriptional changes of yeast cells during full-scale industrial brewing processes with a view to determining the environmental factors influencing the cells oxidative stress response. Cellular antioxidant levels were monitored throughout an industrial propagation and fermentation and microarray analysis was employed to determine transcriptional changes in antioxidant-encoding and other stress response genes. The greatest increase in cellular antioxidants and transcription of antioxidant-encoding genes occurred as the rapidly fermentable sugars glucose and fructose were depleted from the growth medium (wort) and the cell population entered the stationary phase. The data suggest that, contrary to expectation, the oxidative stress response is not influenced by changes in the dissolved oxygen concentration of wort but is initiated as part of a general stress response to growth-limiting conditions, even in the absence of oxygen. A mechanism is proposed to explain the changes in antioxidant response observed in yeast during anaerobic fermentation. The results suggest that the yeast cell does not experience oxidative stress, per se, during industrial brewery handling. This information may be taken into consideration when setting parameters for industrial brewery fermentation.
The oxidative stress response of a lager brewing yeast strain during industrial propagation and fermentation.
Age
View SamplesIn the developing brain, heightened plasticity during the critical period enables the proper formation of neural circuits. Here we identify the “navigator” neurons, a group of perinatally born olfactory sensory neurons, as playing an essential role in establishing the olfactory map during the critical period. The navigator axons project circuitously in the olfactory bulb and traverse multiple glomeruli before terminating in perspective glomeruli. These neurons undergo a phase of exuberant axon growth and exhibit a shortened lifespan. Single cell transcriptome analyses reveal distinct molecular signatures for the navigators. Extending their lifespan prolongs the period of exuberant growth and perturbs axon convergence. Conversely, genetic ablation experiment indicates that, despite postnatal neurogenesis, only the navigators are endowed with the ability to establish a convergent map. The presence and the proper removal of the navigator neurons are both required to establish tight axon convergence into the glomeruli. Overall design: 10X scRNA-seq was preformed on 4 samples of 4 ages of the olfactory epethelium of CD-1 mice. These ages were postanatal days 0, 3, 7, 21.
A Population of Navigator Neurons Is Essential for Olfactory Map Formation during the Critical Period.
Specimen part, Cell line, Subject
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