We used the flu mutant of Arabidopsis and a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX) to address the interactions between different reactive oxygen species (ROS) signaling pathways. The conditional flu mutant of Arabidopsis accumulates excess protochlorophyllide in the dark within chloroplast membranes that upon illumination acts as a photosensitizer and generates singlet oxygen (1O2). Immediately after the release of singlet oxygen rapid changes in nuclear gene expression occur. Distinct sets of genes were activated that were different from those induced by other reactive oxygen species, superoxide or hydrogen peroxide (H2O2), suggesting that different types of active oxygen species activate distinct signaling pathways. It was not known whether the pathways operate separately or interact with each other. We have addressed this problem by modulating noninvasively the level of H2O2 in plastids by means of a transgenic line that overexpresses the thylakoid-bound ascorbate peroxidase (tAPX, line 14/2 PMID: 15165186). In the flu mutant overexpressing tAPX, the expression of most of the nuclear genes that were rapidly activated after the release of 1O2 was significantly higher in flu plants overexpressing tAPX, whereas in wild-type plants, overexpression of tAPX had only a very minor impact on nuclear gene expression. The results suggest that H2O2 antagonizes the 1O2-mediated signaling of stress responses as seen in the flu mutant. This cross-talk between H2O2- and 1O2-dependent signaling pathways might contribute to the overall stability and robustness of wild-type plants exposed to adverse environmental stress conditions.
Cross-talk between singlet oxygen- and hydrogen peroxide-dependent signaling of stress responses in Arabidopsis thaliana.
No sample metadata fields
View SamplesEpithelial Splicing Regulatory Proteins 1 and 2 (ESRP1 and ESRP2) are recently discovered epithelial-specific RNA-binding proteins that promote splicing of the epithelial variant of the FGFR2, ENAH, CD44, and CTNND1 transcripts. To catalogue a larger set of splicing events under the regulation of the ESRPs, we profiled splicing changes induced by RNA interference-mediated knockdown of ESRP1 and ESRP2 expression in a human epithelial cell line using the splicing-sensitive Affymetrix Exon ST1.0 Arrays. Analysis of the microarray data using the previously described MADS tool resulted in the identification of over a hundred candidate ESRP-regulated splicing events. We were able to independently validate 37 of these targets by RT-PCR. The ESRP-regulated events encompass all known types of alternative splicing events. Importantly, a number of these regulated splicing events occur in gene transcripts that encode proteins with well-described roles in the regulation of actin cytoskeleton organization, cell-cell adhesion, cell polarity, and cell migration. In sum, this work reveals a novel list of transcripts differentially spliced in epithelial and mesenchymal cells, implying that coordinated alternative splicing plays a critical role in determination of cell type identity.
The epithelial splicing factors ESRP1 and ESRP2 positively and negatively regulate diverse types of alternative splicing events.
Specimen part, Cell line
View SamplesThe epithelial to mesenchymal transition (EMT) is an essential biological process during embryonic development and has also been implicated in cancer metastasis. Previous studies have characterized transcriptional regulation and key transcription factors that impact EMT. However, the role of alternative splicing (AS) regulation in EMT has only recently emerged and remains relatively uncharacterized. Here we used a robust in vitro EMT model to dynamically and comprehensively characterize splicing switches during EMT in a temporal manner. Overall design: We generated a H358 clone stably expressing a doxycycline (Dox)-inducible cDNA encoding a Zeb1-mCherry fusion protein. Over a 7-day time course following Dox treatment, cells have undergone EMT. We harvested total RNA and protein at each day of the EMT time course and a no Dox-treated control in biological triplicates. We made cDNA libraries for each replicate and subjected them to RNA-seq.
Determination of a Comprehensive Alternative Splicing Regulatory Network and Combinatorial Regulation by Key Factors during the Epithelial-to-Mesenchymal Transition.
No sample metadata fields
View SamplesEpithelial specific splicing regulatory protein 1 and 2 (ESRP1 and ESRP2) are important regulators of alternative splicing during EMT. To study the alternative splicing events regulated by ESRP1/2 at a genome wide scale, we used lentiviral shRNAs to knockdown ESRP1/2 in H358 cells and performed RNA-seq in biological triplicates. Overall design: We used lentiviral based shRNAs targeting ESRP1 and ESRP2 to knockdown both regulators in human H358 cells. We harvested total RNA and protein from ESRP1/2 knockdown and control knockdown in biological triplicates. We made cDNA libraries for each replicate and subjected them to RNA-seq.
Determination of a Comprehensive Alternative Splicing Regulatory Network and Combinatorial Regulation by Key Factors during the Epithelial-to-Mesenchymal Transition.
No sample metadata fields
View SamplesChanges in gene expression on MNV infection of RAW264.7 cells
Murine norovirus replication induces G0/G1 cell cycle arrest in asynchronously growing cells.
Cell line
View SamplesInhibition of the myostatin signaling pathway is emerging as a promising therapeutic means to treat muscle wasting disorders. Activin type IIB receptor is the putative myostatin receptor, and a soluble activin receptor (ActRIIB-Fc) has been demonstrated to potently inhibit a subset of TGF- family members including myostatin. In order to determine reliable and valid biomarkers for myostatin pathway inhibition, we assessed gene expression profiles for quadriceps muscles from mice treated with ActRIIB-Fc compared to mice genetically lacking myostatin and control mice.
Gene expression profiling of skeletal muscles treated with a soluble activin type IIB receptor.
Sex, Age, Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Combined analysis of oligonucleotide microarray data from transgenic and knockout mice identifies direct SREBP target genes.
Sex, Specimen part
View SamplesThe synthesis of fatty acids and cholesterol is regulated by three membrane-bound transcription factors: sterol regulatory element-binding proteins (SREBP)-1a, -1c, and -2. Their function in liver has been characterized in transgenic mice that overexpress each SREBP isoform and in mice that lack all three nuclear SREBPs because of gene knockout of SREBP cleavage-activating protein (SCAP) required for nuclear localization of SREBPs. Here, we use oligonucleotide arrays hybridized with RNA from livers of three lines of mice (transgenic for SREBP-1a, transgenic for SREBP-2, and knockout for SCAP) to identify genes that are likely to be direct targets of SREBPs in liver. Application of stringent combinatorial criteria to the transgenic/knockout approach allows identification of genes whose activities are likely controlled directly by the SREBPs.
Combined analysis of oligonucleotide microarray data from transgenic and knockout mice identifies direct SREBP target genes.
Sex, Specimen part
View SamplesThe synthesis of fatty acids and cholesterol is regulated by three membrane-bound transcription factors: sterol regulatory element-binding proteins (SREBP)-1a, -1c, and -2. Their function in liver has been characterized in transgenic mice that overexpress each SREBP isoform and in mice that lack all three nuclear SREBPs because of gene knockout of SREBP cleavage-activating protein (SCAP) required for nuclear localization of SREBPs. Here, we use oligonucleotide arrays hybridized with RNA from livers of three lines of mice (transgenic for SREBP-1a, transgenic for SREBP-2, and knockout for SCAP) to identify genes that are likely to be direct targets of SREBPs in liver. Application of stringent combinatorial criteria to the transgenic/knockout approach allows identification of genes whose activities are likely controlled directly by the SREBPs.
Combined analysis of oligonucleotide microarray data from transgenic and knockout mice identifies direct SREBP target genes.
Sex, Specimen part
View SamplesThe synthesis of fatty acids and cholesterol is regulated by three membrane-bound transcription factors: sterol regulatory element-binding proteins (SREBP)-1a, -1c, and -2. Their function in liver has been characterized in transgenic mice that overexpress each SREBP isoform and in mice that lack all three nuclear SREBPs because of gene knockout of SREBP cleavage-activating protein (SCAP) required for nuclear localization of SREBPs. Here, we use oligonucleotide arrays hybridized with RNA from livers of three lines of mice (transgenic for SREBP-1a, transgenic for SREBP-2, and knockout for SCAP) to identify genes that are likely to be direct targets of SREBPs in liver. Application of stringent combinatorial criteria to the transgenic/knockout approach allows identification of genes whose activities are likely controlled directly by the SREBPs.
Combined analysis of oligonucleotide microarray data from transgenic and knockout mice identifies direct SREBP target genes.
Sex, Specimen part
View Samples