ISWI is an evolutionary conserved ATPase that catalyzes nucleosome remodeling in several different complexes. Two mammalian ISWI orthologs, SNF2H and SNF2L, have specialized functions despite their high similarity. Due to the lack of reagents the functions of SN2L in human cells had not been established. Newly established specific monoclonal antibodies and selective RNA interference protocols now enabled a comprehensive characterization of loss-of-function phenotypes in human cells. Contrasting earlier results obtained in the mouse model, we found SNF2L broadly expressed in primary human tissues. Depletion of SNF2L in HeLa cells led to enhanced proliferation, morphological alterations and increased migration. These phenomena were explained by transcriptome profiling, which identified SNF2L as a modulator of the Wnt signaling network. The cumulative effects of SNF2L depletion on gene expression portray the cell in a state of activated Wnt signaling characterized by increased proliferation and chemotactic locomotion. High levels of SNF2L expression in normal melanocytes contrast to undetectable expression in malignant melanoma. In summary, our data document an anti-correlation between SNF2L expression and several features characteristic of malignant cells.
Nucleosome remodeler SNF2L suppresses cell proliferation and migration and attenuates Wnt signaling.
Cell line
View SamplesThe genome of Epstein-Barr virus (EBV) encodes 86 proteins but only a limited set is expressed in EBV-growth transformed B cells, termed lymphoblastoid cell lines (LCLs). These cells proliferate via the concerted action of EBV nuclear antigens (EBNAs) and latent membrane proteins (LMPs), some of which are rate limiting to establish a stable homeostasis of growth promoting and anti-apoptotic activities. We show here that EBV mutants, which lack the EBNA-3A gene, are impaired but can still initiate cell-cycle entry and proliferation of primary human B cells in contrast to an EBNA-2-deficient mutant virus. Surprisingly and in contrast to previous reports, these viral mutants are attenuated in growth transformation assays but give rise to permanently growing EBNA-3A negative B cell lines which exhibit reduced proliferation rates and elevated levels of apoptosis. Expression profiles of EBNA-3A deficient LCLs are characterized by 129 upregulated and 167 downregulated genes, which are significantly enriched for genes involved in apoptotic processes or cell cycle progression like the tumor suppressor gene p16/INK4A or might contribute to essential steps in the viral life cycle. In addition EBNA-3A cellular target genes remarkably overlap with previously identified targets of EBNA-2.
Differential gene expression patterns of EBV infected EBNA-3A positive and negative human B lymphocytes.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The impact of TEL-AML1 (ETV6-RUNX1) expression in precursor B cells and implications for leukaemia using three different genome-wide screening methods.
Specimen part, Disease, Disease stage, Cell line
View SamplesSmall regulatory RNAs including small interfering RNAs (siRNAs) and microRNAs (miRNAs) guide Argonaute (Ago) proteins to specific target RNAs leading to mRNA destabilization or translational repression. We recently reported the identification of Importin 8 (Imp8) as a novel component of miRNA-guided regulatory pathways. Imp8 interacts with Ago proteins and localizes to cytoplasmic processing bodies (P-bodies), structures involved in RNA metabolism. For this micro-array dataset, we used immunoprecipitations of Ago2-associated mRNAs followed by micro-array analysis. The results demonstrate that Imp8 is required for recruiting Ago protein complexes to a large set of Ago2-associated target mRNAs allowing for efficient and specific gene silencing. Therefore, we provide evidence that Imp8 is required for cytoplasmic miRNA-guided gene silencing.
Importin 8 is a gene silencing factor that targets argonaute proteins to distinct mRNAs.
No sample metadata fields
View SamplesWe identified directly and indirectly regulated target genes utilizing an inducible TEL-AML1 system derived from the murine pro B-cell line BA/F3 and a monoclonal antibody directed against TEL-AML1. By integration of promoter binding identified with ChIP-on-chip, gene expression and protein output through microarray technology and stable labelling of amino acids in cell culture (SILAC), we identified directly and indirectly regulated targets of the TEL-AML1 fusion protein.
The impact of TEL-AML1 (ETV6-RUNX1) expression in precursor B cells and implications for leukaemia using three different genome-wide screening methods.
Cell line
View SamplesThe estrogen receptor-alpha (ER) determines breast cancer cell phenotype and is a prognostic indicator. A better understanding of the mechanisms controlling ER function may uncover improved strategies for the treatment of breast cancer. Proteasome inhibition was previously reported to regulate estrogen-induced transcription but the mechanisms by which it influences ER function remain controversial. In this study we investigated the transcriptome-wide effects of the proteasome inhibitor Velcade on estrogen-regulated transcription in MCF7 human breast cancer cells and demonstrate a specific global decrease in estrogen-induced transcription.
Estrogen-dependent gene transcription in human breast cancer cells relies upon proteasome-dependent monoubiquitination of histone H2B.
Cell line
View SamplesNucleosomal incorporation of specialized histone variants is an important mechanism to generate different functional chromatin states. Here we report the identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y. Their mRNAs are found in certain human cell lines, in addition to several normal and malignant human tissues. In keeping with their primate-specificity, H3.X and H3.Y are detected in different brain regions. Transgenic H3.X and H3.Y proteins are stably incorporated into chromatin in a similar fashion to the known H3 variants. Importantly, we demonstrate biochemically and by mass spectrometry that endogenous posttranslationally modified H3.Y protein exists in vivo, and that stress-stimuli, such as starvation and cellular density, increase the abundance of H3.Y-expressing cells. Global transcriptome analysis revealed that knock-down of H3.Y affects cell growth and leads to changes in the expression of many genes involved in cell cycle control. Thus, H3.Y is a novel histone variant involved in the regulation of cellular responses to outside stimuli.
Identification and characterization of two novel primate-specific histone H3 variants, H3.X and H3.Y.
Cell line
View SamplesTranscription factor FoxQ1 belongs to family of Fox transcription factors containing forkhead box (winged helix) domain. This family of proteins plays an important role in cell growth, proliferation, and differentiation. Expression of FoxQ1 was found in cancer cells and was associated with increased migration and invasion. Recently, elevated FoxQ1 expression was found in IL4 stimulated macrophages.
IL-4 driven transcription factor FoxQ1 is expressed by monocytes in atopic dermatitis and stimulates monocyte migration.
Cell line
View SamplesThe objective of this study was the assessment of transcriptional dysregulation in particular with regard to B-cell differentiation factors. Most studies focus on cross-section analyses of various leukemia subtypes to identify differentially regulated genes lacking suitable reference models. Here we applied comparative intraindividual transcriptome analysis of B-precursor ALL of childhood, which introduces a side-by-side analysis of leukemic cells and matched normal lymphoblasts from the same individual in complete continuous remission after the end of re-induction therapy. This approach reduces noise by eliminating interindividual variability.
Aberrant ZNF423 impedes B cell differentiation and is linked to adverse outcome of ETV6-RUNX1 negative B precursor acute lymphoblastic leukemia.
Specimen part, Subject
View SamplesWhole transcriptome for PRMT6 knock-out and control NT2/D1 cells with and without ATRA (all-trans retinoic acid) was sequenced. These samples were compared to each other to find differentially regulated genes and PRMT6-dependent transcriptome in pluripotency and differentiating cells. Overall design: Examining of PRMT6-dependent transcriptome in NT2/D1 cells using RNAseq.
Genomic Location of PRMT6-Dependent H3R2 Methylation Is Linked to the Transcriptional Outcome of Associated Genes.
Specimen part, Cell line, Subject
View Samples