The subunits of voltage-gated calcium channels regulate surface expression and gating of CaV1 and CaV2 1 subunits, and thus contribute to neuronal excitability, neurotransmitter release and calcium-induced gene regulation. In addition certain subunits are targeted into the nucleus, where they directly interact with the epigenetic machinery. Whereas their involvement in this multitude of functions is reflected by a great molecular heterogeneity of isoforms derived from four genes and abundant alternative splicing, little is known about the roles of individual variants in specific neuronal functions. In the present study, an alternatively spliced 4 subunit lacking the variable N-terminus (4e) is identified. It is highly expressed in mouse cerebellum and cultured cerebellar granule cells (CGC) and modulates P/Q-type calcium currents in tsA cells and CaV2.1 surface expression in neurons. Compared to the other two known full-length 4 variants (4a, 4b) 4e is most abundantly expressed in the distal axon, but lacks nuclear targeting properties. To examine the importance of nuclear targeting of 4 subunits for transcriptional regulation, we performed whole genome expression profiling of CGCs from lethargic mice individually reconstituted with 4a, 4b, and 4e. Notably, the number of genes regulated by each 4 splice variant correlated with the rank order of their nuclear targeting properties (4b> 4a> 4e). Together these findings support isoform-specific functions of 4 splice variant in neurons, with 4b playing a dual role in channel modulation and gene regulation, while the newly detected 4e variant serves exclusively in calcium channel-dependent functions.
Differential neuronal targeting of a new and two known calcium channel β4 subunit splice variants correlates with their regulation of gene expression.
Specimen part
View SamplesDifferentiation assays with neural progenitor cells of the enteric nervous system (ENS) showed elongated neurite outgrowth under influence of 3,5,3'-Triiodothyronine (concentrations 50 nm and 100 nm). For analysis, neural cells were stained with TUJ1 (beta-Tubulin III). Microarray analysis should enlighten these results on a genetical basis and give hints about the regulation pathways.
Molecular and cell biological effects of 3,5,3'-triiodothyronine on progenitor cells of the enteric nervous system in vitro.
Specimen part, Treatment
View SamplesThe goal of this study was to investigate the role of intragenic CTCF in alternative pre-mRNA splicing through a combined CTCF-ChIP-seq and RNA-seq approach. CTCF depletion led to decreased inclusion of weak upstream exons. Overall design: CTCF ChIP-seq was performed in BJAB and BL41 B cell lines and normalized relative to Rabbit Ig control IP-seq reads. RNA-seq was performed in BJAB and BL41 cells transduced with shRNA against CTCF or RFP as a control, and in untransduced cells as well.
CTCF-promoted RNA polymerase II pausing links DNA methylation to splicing.
Cell line, Subject
View SamplesHuman testicular cells were isolated mechanically and enzymatically from testis of braindead donors and from urological samples. The expression of genes was studied at baseline and 1,25(OH)2D treated conditions.
Testicular synthesis and vitamin D action.
Specimen part
View SamplesWe have determined that verticillin A is a histone methyltransfease inhibitor that selectively inhibits human SUV39H1, SUV39H2, G9a and GLP to inhibit H3K9 methylation in human colon cancer cells. The objective here is to identify verticillin A target genes in human colon cancer cells.
H3K9 Trimethylation Silences Fas Expression To Confer Colon Carcinoma Immune Escape and 5-Fluorouracil Chemoresistance.
Cell line, Treatment
View SamplesMonocyte chemoattractant protein 1 (MCP-1/CCL2) is critically involved in directing the migration of blood monocytes to sites of inflammation. Consequently, excessive MCP-1 secretion has been linked to many (auto)inflammatory diseases, whereas a lack of expression severely impairs immune responsiveness. We demonstrate that the atypical inhibitor of NF-B (IB), a transcriptional co-activator required for the selective expression of a subset of NF-B target genes, is a key activator of the Ccl2 gene. IB-deficient macrophages exhibited impaired secretion of MCP-1 when challenged with diverse inflammatory stimuli, such as lipopolysaccharide or peptidoglycan. These findings were reflected at the level of Ccl2 gene expression, which was tightly coupled to the presence of IB. Moreover, mechanistic insights acquired by chromatin immunoprecipitation demonstrate that IB is directly recruited to the proximal promoter region of the Ccl2 gene and required for histone H3K9 trimethylation. Finally, IB-deficient mice showed significantly impaired MCP-1 secretion and monocyte infiltration in an experimental model of peritonitis. Together, these findings suggest a distinguished role of IB in mediating the targeted recruitment of monocytes in response to local inflammatory events.
IκBζ is a transcriptional key regulator of CCL2/MCP-1.
Sex, Specimen part
View SamplesAstrocytes react to brain injury in a heterogeneous manner with only a subset resuming proliferation and acquiring in vitro neural stem cell properties. In order to identify novel regulators of this astrocyte subset, we performed a genome-wide expression analysis of reactive astrocytes isolated 5 days after stab wound injury from the adult mouse cerebral cortex. The expression pattern was compared with astrocytes from normal cortex and adult neural stem cells isolated from the sub-ependymal zone (GSE18765). These comparisons revealed a set of genes up-regulated both in neurogenic neural stem cells and reactive astrocytes, including the lectins Galectin-1 and -3. These results, as well as the pattern of Galectin expression in the lesioned brain, led us to examine the functional significance of these lectins in brains of Galectin-1/3 double-knockout mice.
Astrocyte reactivity after brain injury-: The role of galectins 1 and 3.
Sex, Specimen part, Treatment, Time
View SamplesSilymarin (SM) is a popular botanical medicine with purported liver protective effects. SM displays multiple effects in animal models and in cell culture including prevention of liver disease, reduction of inflammation, oxidative stress, and proliferation. Despite a plethora of data indicating that SM impinges on multiple cellular signaling pathways important in inflammation and disease, no unifying mechanisms have been forwarded. To define how SM elicits so many biological effects, the current study presents the first comprehensive transcriptional profiling study of human hepatoma cells treated with SM. The intention of the study was to focus on the early transcriptional events that are associated with SM-induced inhibition of proliferation and inflammation. Collectively, the data demonstrate that SM causes a rapid transcriptional reprogramming of cells that initially manifests as energy stress and slowing of cellular metabolism, leading to inhibition of cell growth and inflammation.
Silymarin Suppresses Cellular Inflammation By Inducing Reparative Stress Signaling.
Specimen part, Cell line, Treatment, Time
View SamplesWe studied changes in a whole transcriptome during dsDNA virus infection. Overall design: Fibroblasts (MRC5 & HFF) and epithelial cells (ARPE19) were infected with HCMV, HSV1 or Ad5 and total RNA was isolated at 48, 9, or 24 hpi, respectively. Total 15 treatments were used. There were 2 biological replicates analyzed per each treatment.
A tumor-specific endogenous repetitive element is induced by herpesviruses.
Specimen part, Subject
View SamplesWe studied changes in a whole transcriptome during HCMV infection. Overall design: Fibroblasts (MRC5) were infected with HCMV and total RNA was isolated at 48. Total 2 individual samples were used. There were 3 replicates analyzed per individual sample.
A tumor-specific endogenous repetitive element is induced by herpesviruses.
Specimen part, Subject
View Samples