A transgenic mouse was generated using a CD2-driven transgene containing the cDNA of Ppp2ca to achieve over-expression of PP2Ac in T cells. Nave CD4 T cells were isolated and lysed at times 0, 6, and 24 hours after stimulation with anti-CD3 and anti-CD28
Protein phosphatase 2A enables expression of interleukin 17 (IL-17) through chromatin remodeling.
No sample metadata fields
View SamplesThis sudy focuses on the identification of transcripts in the shoot phloem of the model plant Arabidopsis thaliana. Transcripts expressed in the phloem tissue (parenchyma cell, companion cell, sieve element) were excised by laser microdissection pressure catapulting (LMPC). These were compared with transcripts isolated from leaf phloem exudates by EDTA-chelation technique. Optimization of sample harvest resulted in RNA of high quality from both sources. Modifications of the RNA amplification procedure obtained RNA of sufficient yield and quality for microarray experiments. Microarrays (Affymetrix, ATH1) hybridized with RNA derived from phloem tissue by LMPC or phloem sap allowed us to differentiate between phloem located and mobile transcript species. The datasets provide a search criterion for phloem-based signals and will facilitate reverse genetic studies and forward genetic screens for phloem and long distance RNA signaling mutants.
Identification of Arabidopsis thaliana phloem RNAs provides a search criterion for phloem-based transcripts hidden in complex datasets of microarray experiments.
No sample metadata fields
View SamplesRay cells were enriched from wood samples of poplar (Populus x canescens) by LMPC and transcripts monitored by poplar whole genome microarrays. Results provided insight into molecular processes during the transition from dormancy to flowering in early spring in contrast to the active growth phase in summer.
Poplar wood rays are involved in seasonal remodeling of tree physiology.
No sample metadata fields
View SamplesAbstract: Interleukin-10-deficient (Il10-/-) mice serve as a model for inflammatory bowel disease (IBD). The severity of colitis strongly depends on the inbred strain carrying the disrupted Il10 gene: C3H/HeJBir (C3) confers disease susceptibility, whereas C57BL/6J (B6) confers resistance. Genome-wide scans with microsatellite markers on segregrating backcross and F2 populations resulted in the detection of ten colitogenic quantitative trait loci (QTL). The aim of this study was to reduce the large number of candidate genes within the QTL intervals by identifying those genes which are located within the candidate gene intervals and which are differentially expressed in the colon of IBD-susceptible and -resistant strains. Using this combination of QTL mapping and microarray analysis, we identified 16 genes which were differentially expressed between B6- and C3-Il10-/- mice and were located within the candidate gene intervals. Three of these genes (Pla2g2a, Gbp1, Cd14) showed prominent differences in expression levels between B6- and C3-Il10-/- as well as between B6 and C3 wildtype mice and were considered to be major candidate genes. Pla2g2a and Gbp1 are known to be polymorphic between C3 and B6 mice. Expression data for Cd14 were confirmed by real-time RT PCR using specified pathogen free and germfree Il10-/- mice. In conclusion, the large number of candidate genes was reduced to three major candidates by using a combination of QTL mapping and microarray analysis. All three genes play an important role in inflammatory processes and immune response.
Cd14, Gbp1, and Pla2g2a: three major candidate genes for experimental IBD identified by combining QTL and microarray analyses.
No sample metadata fields
View SamplesWe compared splenic Va14i NKT cells from C57BL/6 control mice and from mice injected 4 weeks earlier intravenously with 4ug/mouse of the iNKT cell antigen alpha-galactosylceramide (aGalCer). These mice were either left unstimulated or were stimulated with 1ug/mouse aGalCer i.v.. All mice were female and 8 weeks of age at the beginning of the experiment. Va14i NKT cells were enriched via magnetic selection and cell sorted for TCRb+ CD1d/aGalCer-tetramer+. Total RNA were prepared using a Qiagen RNeasy mini kit. IVT probe generation and hybridization to Affymetrix Mouse Genome 430 2.0 arrays was carried out by the Veterans Medical Research Foundation GeneChipTM Microarray located at UCSD.
IL-10-producing NKT10 cells are a distinct regulatory invariant NKT cell subset.
Sex, Age, Specimen part, Treatment
View SamplesThe forkhead O transcription factors (FOXO) integrate a range of extracellular signals including growth factor signaling, inflammation, oxidative stress and nutrient availability, to substantially alter the program of gene expression and modulate cell survival, cell cycle progression, and many cell-type specific responses yet to be unraveled. Naive antigen-specific CD8+ T cells undergo a rapid expansion and arming of effector function within days of pathogen exposure, but in addition, by the peak of expansion, they form precursors to memory T cells capable of self-renewal and indefinite survival.
Differentiation of CD8 memory T cells depends on Foxo1.
Specimen part
View SamplesBackground and Aims: In the interleukin-10-deficient (Il10-/-) mouse model of IBD, 10 quantitative trait loci (QTL) have been shown to be associated with colitis susceptibility by linkage analyses on experimental crosses of highly susceptible C3H/HeJBir (C3Bir)-Il10-/- and partially resistant C57BL/6J (B6)-Il10-/- mice. The strongest locus (C3Bir-derived cytokine deficiency-induced colitis susceptibility [Cdcs]1 on Chromosome [Chr] 3) controlled multiple colitogenic subphenotypes and contributed the vast majority to the phenotypic variance in cecum and colon. This was demonstrated by interval-specific Chr 3 congenic mice wherein defined regions of Cdcs1 from C3Bir or B6 were bred into the IL-10-deficient reciprocal background and altered the susceptible or resistant phenotype. Furthermore, this locus likely acts by inducing innate hypo- and adaptive hyperresponsiveness, associated with impaired NFB responses of macrophages. The aim of the present study was to dissect the complexity of Cdcs1 by further development and characterization of reciprocal Cdcs1 congenic strains and to identify potential candidate genes in the congenic interval. Material and Methods: In total, 15 reciprocal congenic strains were generated from Il10-/- mice of either C3H/HeJBir or C57BL/6J backgrounds by 10 cycles of backcrossing. Colitis activity was monitored by histological grading. Candidate genes were identified by fine mapping of congenic intervals, sequencing, microarray analysis and a high-throughput real-time RT-PCR approach using bone marrow-derived macrophages. Results: Within the originally identified Cdcs1-interval, three independent regions were detected that likely contain susceptibility-determining genetic factors (Cdcs1.1, Cdcs1.2, and Cdcs1.3). Combining results of candidate gene approaches revealed Fcgr1, Cnn3, Larp7, and Alpk1 as highly attractive candidate genes with polymorphisms in coding or regulatory regions and expression differences between susceptible and resistant mouse strains. Conclusions: Subcongenic analysis of the major susceptibility locus Cdcs1 on mouse chromosome 3 revealed a complex genetic structure. Candidate gene approaches revealed attractive genes within the identified regions with homologs that are located in human susceptibility regions for IBD.
Cdcs1 a major colitis susceptibility locus in mice; subcongenic analysis reveals genetic complexity.
Sex, Specimen part
View SamplesEffective immune responses depend upon appropriate T cell differentiation in accord with the nature of an infectious agent, and the contingency of differentiation depends minimally on T cell antigen receptor, co-receptor, and cytokine signals. In this reverse genetic study we show that the Map Kinase, Erk2, is nonessential for T cell proliferation in the presence of optimum co-stimulation. Instead, it has opposite polar effects on T-bet and Gata3 expression and hence on Th1 and Th2 differentiation. Alternatively, in the presence of TGFbeta, the Erk pathway suppresses a large program of gene expression effectively limiting the differentiation of Foxp3+ T reg cells. In the latter case, the mechanisms involved include suppression of Gata3 and Foxp3, induction of Tbx21, phosphorylation of Smad2,3, and possibly suppression of Socs2, a positive inducer of Stat5 signaling. Consequently, loss of Erk2 severely impeded Th1 differentiation while enhancing the development of Foxp3+ induced T regulatory cells. Selected profiles of gene expression under multiple conditions of T cell activation illustrate the opposing consequences of Erk pathway signaling.
Polar opposites: Erk direction of CD4 T cell subsets.
Specimen part, Time
View SamplesThe intention of these gene expression analysis was to study host responses to an infection with Agrobacterium tumefaciens at different stages of crown gall development. Therefore the transcriptome of infected inflorescence stalk tissue and mature crown galls of Arabidopsis thaliana (WS-2) was determined of three different time points. These were compared with the transcriptome of mock-infected inflorescence stalk tissue (reference) of the same age. The following time points were analyzed: (i) three hours post inoculation, before the T-DNA is integrated into the host genome (ii) six days after inoculation when the T-DNA is present in the nucleus and the oncogenes are expressed in the host cell, and (iii) 35 days after inoculation when a mature tumors has developed. For the three-hour- (3hpi) and six-day- time point (6dpi) plants were infected with the virulent strain C58, harboring a T-DNA, or with strain GV3101, containing a disarmed Ti-plasmid. This allows discrimination between signals which derive from the bacterial pathogen and the T-DNA encoded oncogenes.
An integrated view of gene expression and solute profiles of Arabidopsis tumors: a genome-wide approach.
Specimen part
View SamplesThis study focuses on responses of the host plant to infection with Agrobacterium tumefaciens. Genome wide changes in gene expression were integrated with the alterations in metabolite levels three hours after inoculation of agrobacteria. Plants were infected with the virulent strain C58, harboring a T-DNA, or with strain GV3101, containing a disarmed Ti-plasmid. This allows discrimination between signals which derive from the bacterial pathogen and the T-DNA encoded genes.
An integrated view of gene expression and solute profiles of Arabidopsis tumors: a genome-wide approach.
Specimen part
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