Background: Insulin's effect on protein synthesis (translation of transcripts) and post-translational modifications, especially those involving reversible modifications such as phosphorylation of various signaling proteins, are extensively studied. On the other hand, insulin's effect on the transcription of genes, especially of transcriptional temporal patterns, is not well investigated in the literature.
Function-based discovery of significant transcriptional temporal patterns in insulin stimulated muscle cells.
Specimen part, Cell line, Treatment
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 SamplesEpithelial-mesenchymal transition (EMT) and mesenchymal-epithelial transition (MET) facilitate breast cancer (BC) metastasis, however stable molecular changes that result as a consequence of these processes remain poorly defined. Therefore, we sought to identify molecular markers that could distinguish tumor cells that had completed the EMT:MET cycle in the hopes of identifying and targeting unique aspects of metastatic tumor outgrowth.Therefore, normal murine mammary gland (NMumG) cells transformed by overexpression of EGFR (NME) cells were cultured in the presence of TGF-beta1 (5 ng/ml) for 4 weeks, at which point TGF-beta1 supplementation was discontinued and the cells were allowed to recover for an additional 4 weeks (Post-TGF-Rec). Total RNA was prepared from unstimulated cells (Pre-TGF) of similar passage and compared by microarray analysis.
Fibroblast growth factor receptor splice variants are stable markers of oncogenic transforming growth factor β1 signaling in metastatic breast cancers.
Specimen part
View SamplesThe protease activity of the paracaspase MALT1 plays an important role in antigen receptor-mediated lymphocyte activation by controlling the activity of the transcription factor NF-kB and is thus essential for the expression of inflammatory target genes.
MALT1 Protease Activity Controls the Expression of Inflammatory Genes in Keratinocytes upon Zymosan Stimulation.
Treatment
View SamplesNaturally occurring variations of Polycomb Repressive Complex 1 (PRC1) comprise a core assembly of Polycomb group proteins and additional factors that include, surprisingly, Autism Susceptibility Candidate 2 (AUTS2). While AUTS2 is often disrupted in patients with neuronal disorders, the underlying mechanism is unclear. We investigated the role of AUTS2 as part of a previously identified PRC1 complex (PRC1-AUTS2), and in the context of neurodevelopment. In contrast to the canonical role of PRC1 in gene repression, PRC1-AUTS2 activates transcription. Biochemical studies demonstrate that the CK2 component of PRC1-AUTS2 thwarts PRC1 repressive activity and AUTS2-mediated recruitment of P300 leads to gene activation. ChIP-seq of AUTS2 shows that it regulates neuronal gene expression through promoter association. Conditional CNS targeting of Auts2 in a mouse model leads to various developmental defects. These findings reveal a natural means of subverting PRC1 activity, linking key epigenetic modulators with neuronal functions and diseases. Overall design: mRNA profiles of P1 brain from wild type mice were generated by deep sequencing
An AUTS2-Polycomb complex activates gene expression in the CNS.
No sample metadata fields
View SamplesThe pesticide rotenone, a neurotoxin that inhibits the mitochondrial complex I, and destabilizes microtubules (MT) has been linked to Parkinson disease (PD) etiology and is often used to model this neurodegenerative disease (ND). Many of the mechanisms of action of rotenone are posited mechanisms of neurodegeneration; however, they are not fully understood. Therefore, the study of rotenone-affected functional pathways is pertinent to the understanding of NDs pathogenesis. This report describes the transcriptome analysis of a neuroblastoma (NB) cell line chronically exposed to marginally toxic and moderately toxic doses of rotenone. The results revealed a complex pleiotropic response to rotenone that impacts a variety of cellular events, including cell cycle, DNA damage response, proliferation, differentiation, senescence and cell death, which could lead to survival or neurodegeneration depending on the dose and time of exposure and cell phenotype. The response encompasses an array of physiological pathways, modulated by transcriptional and epigenetic regulatory networks, likely activated by homeostatic alterations. Pathways that incorporate the contribution of MT destabilization to rotenone toxicity are suggested to explain complex I-independent rotenone-induced alterations of metabolism and redox homeostasis. The postulated mechanisms involve the blockage of mitochondrial voltage-dependent anions channels (VDACs) by tubulin, which coupled with other rotenone-induced organelle dysfunctions may underlie many presumed neurodegeneration mechanisms associated with pathophysiological aspects of various NDs including PD, AD and their variant forms. Thus, further investigation of such pathways may help identify novel therapeutic paths for these NDs.
Transcriptome analysis of a rotenone model of parkinsonism reveals complex I-tied and -untied toxicity mechanisms common to neurodegenerative diseases.
Cell line, Treatment, Time
View SamplesWNT-induced secreted protein 1 (WISP1/CCN4), a member of the CCN protein family, acts as a downstream factor of the canonical WNT-signaling pathway. A dysregulated expression of WISP1 often reflects its oncogenic potential by inhibition of apoptosis, a necessary form of cell death that protect cell populations for transformation into malignant phenotypes. WISP1-signaling is also known to affect proliferation and differentiation of human mesenchymal stem cells (hMSCs), which are fundamental for the constitution and maintenance of the musculoskeletal system. Our study emphasizes the importance of WISP1-signaling for cell survival of primary human cells. Therefore, we established a successful down-regulation of endogenous WISP1 transcripts through gene silencing in hMSCs. We were able to demonstrate the consequence of cell death immediately after WISP1 down-regulation took place. Bioinformatical analyses of subsequent performed microarrays from WISP1 down-regulated vs. control samples confirmed this observation. We uncovered several clusters of differential expressed genes important for cellular apoptosis induction and immuno-regulatory processes, thereby indicating TRAIL-induced and p53-mediated apoptosis as well as IFNbeta-signaling. Since all of them act as potent inhibitors for malignant cell growth, in vitro knowledge about the connection with WISP1-signaling could help to find new therapeutic approaches concerning cancerogenesis and tumor growth in musculoskeletal tissues.
WISP 1 is an important survival factor in human mesenchymal stromal cells.
Specimen part, Treatment
View SamplesStudies investigating the causes of autism spectrum disorder (ASD) point to genetic as well as epigenetic mechanisms of the disease. Identification of epigenetic processes that contribute to ASD development and progression is of major importance and may lead to the development of novel therapeutic strategies. Here we identify the bromodomain and extra-terminal domain containing transcriptional regulators (BETs) as epigenetic drivers of an ASD-like disorder in mice. We found that the pharmacological suppression of the BET proteins by a novel, highly selective and brain-permeable inhibitor, I-BET858, leads to selective suppression of neuronal gene expression followed by the development of an autism-like syndrome in mice. Many of the I-BET858 affected genes have been linked to ASD in humans thus suggesting the key role of the BET-controlled gene network in ASD. Our studies also suggest that environmental factors controlling BET proteins or their target genes may contribute to the epigenetic mechanism of ASD.
Autism-like syndrome is induced by pharmacological suppression of BET proteins in young mice.
Specimen part
View SamplesAs multiple myeloma tumors universally dysregulate cyclin D genes we conducted high-throughput chemical library screens for compounds that induce suppression of cyclin D2. The top-ranked compound was a natural triterpenoid, pristimerin.
Identification of a potent natural triterpenoid inhibitor of proteosome chymotrypsin-like activity and NF-kappaB with antimyeloma activity in vitro and in vivo.
Specimen part
View SamplesIn chicks, the avian homologue of the early growth response protein-1 (ZENK) has been shown to be increased in a special cell type of the retina, the glucagonergic amacrine cells, under conditions that lead to a reduction in eye growth (myopic defocus, recovery of myopia) and decreased under conditions that enhance ocular growth (hyperopic defocus, form-deprivation). The investigation of Egr-1 knock-out mice showed that homozygous knock-out mice with no functional Egr-1 protein developed relative axial myopia at the age of 42 and 56 days, compared to heterozygous- and wildtype Egr-1 knock-out mice.
Microarray analysis of retinal gene expression in Egr-1 knockout mice.
Sex, Age, Specimen part
View Samples