In Arabidopsis, jasmonate is required for stamen and pollen maturation. Mutants deficient in jasmonate synthesis, such as opr3, are male-sterile but become fertile when jasmonate is applied to developing flower buds. We have used ATH1 oligonucleotide arrays to follow gene expression in opr3 stamens for 22 hours following jasmonate treatment. In these experiments, a total of 821 genes were specifically induced by jasmonate and 480 repressed. Comparisons with data from previous studies indicate that these genes constitute a stamen-specific jasmonate transcriptome, with a large proportion (70%) of the genes expressed in the sporophytic tissue but not in the pollen. Bioinformatics tools allowed us to associate many of the induced genes with metabolic pathways that are likely up-regulated during jasmonate-induced maturation. Our pathway analysis led to the identification of specific genes within larger families of homologues that apparently encode stamen-specific isozymes. Extensive additional analysis of our dataset identified 13 transcription factors that may be key regulators of the stamen maturation processes triggered by jasmonate. Two of these transcription factors, MYB21 and MYB24, are the only members of subgroup 19 of the R2R3 family of MYB proteins. A myb21 mutant obtained by reverse genetics exhibited shorter anther filaments, delayed anther dehiscence and greatly reduced male fertility. A myb24 mutant was phenotypically wild type, but production of a myb21myb24 double mutant indicated that introduction of the myb24 mutation exacerbated all three aspects of the myb21 phenotype. Exogenous jasmonate could not restore fertility to myb21 or myb21myb24 mutant plants. Together with the data from transcriptional profiling, these results indicate that MYB21 and MYB24 are induced by jasmonate and mediate important aspects of the jasmonate response during stamen development.
Transcriptional regulators of stamen development in Arabidopsis identified by transcriptional profiling.
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View SamplesSignal transduction processes mediated by phosphatidyl inositol phosphates affect a broad range of cellular processes such as cell cycle progression, migration and cell survival. The protein kinase AKT is one of the major effectors in this signaling network. Chronic AKT activation contributes to oncogenic transformation and tumor development. Therefore, new small drugs were designed to block AKT activity for cancer treatment.
Characterization of AKT independent effects of the synthetic AKT inhibitors SH-5 and SH-6 using an integrated approach combining transcriptomic profiling and signaling pathway perturbations.
Specimen part, Cell line
View SamplesThe objective of the present study was to identify genes that are involved in increasing the ovulation number in mouse line FL1 that had been selected for high fertility performance.
Expression profiling of a high-fertility mouse line by microarray analysis and qPCR.
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View SamplesmRNA expression levels in synovial fibroblasts in 6 rheumatoid arthritis patients versus 6 osteoarthritis patients.
Constitutive upregulation of the transforming growth factor-beta pathway in rheumatoid arthritis synovial fibroblasts.
No sample metadata fields
View SamplesAcute myeloid leukemia (AML) is a heterogeneous disease and AML with normal karyotype (AML-NK) is categorized as an intermediate-risk group. Over the past years molecular analyses successfully identified biomarkers that will further allow to dissecting clinically meaningful subgroups in this disease. Thus far, somatic mutations were identified which elucidate the disturbance of cellular growth, proliferation, and differentiation processes in hematopoietic progenitor cells. In AML-NK, acquired gene mutations with prognostic relevance were identified for FLT3, CEBPA, and NPM1. FLT3-ITD mutations were associated with short relapse-free and overall survival, while mutations in CEBPA or NPM1 (without concomitant FLT3-ITD) had a more favorable outcome.
Quantitative comparison of microarray experiments with published leukemia related gene expression signatures.
Sex, Age, Disease, Disease stage
View SamplesThe purpose of this study was to characterize the transcriptional effects induced by subcutaneous IFN-beta-1b treatment (Betaferon, 250 g every other day) in patients with relapsing-remitting form of multiple sclerosis (MS).
Long-term genome-wide blood RNA expression profiles yield novel molecular response candidates for IFN-beta-1b treatment in relapsing remitting MS.
Sex
View SamplesThe purpose of this study was to characterize the transcriptional effects induced by intramuscular IFN-beta-1a treatment (Avonex, 30 g once weekly) in patients with relapsing-remitting form of multiple sclerosis (MS). By using Affymetrix DNA microarrays, we obtained genome-wide expression profiles of peripheral blood mononuclear cells from 24 MS patients within the first four weeks of IFN-beta administration.
Network analysis of transcriptional regulation in response to intramuscular interferon-β-1a multiple sclerosis treatment.
Sex
View SamplesTwo biological replicate experiments were performed to estimate the bias of the gene expression pattern of infected and non-infected HEp-2 cells. Microarrays hybridized with RNA from 2 h of non-infected HEp-2 cells were used as reference chips for the comparison with microarrays hybridized with RNA from 2 h and 4 h of eukaryotic cells exposed to wt-bacteria and .fasX-mutant. As a reference for chips hybridized with RNA prepared from 6 h p. i. and 8 h p. i. of both GAS-infected HEp-2 cells we used chips that were hybridized with RNA isolated from non-infected cells 8 h p. i. We also compared the microarray data from 2 h of non-infected HEp-2 cells with those from 8 h of non-infected HEp-2 cells to determine the influence of the extended culture on the non-infected cells. Only such genes which were differentially regulated after infection with wt-bacteria and .fasX-mutant infected cells and not differentially present in unequal amounts between the 2 h and 8 h of controls were included in the subsequent statistical analysis.
Global epithelial cell transcriptional responses reveal Streptococcus pyogenes Fas regulator activity association with bacterial aggressiveness.
Disease, Disease stage, Cell line, Time
View SamplesThe organization of mammalian DNA replication is poorly understood. We have produced genome-wide high-resolution dynamic maps of the timing of replication in human erythroid, mesenchymal and embryonic stem cells using TimEX, a method that relies on gaussian convolution of massive, highly redundant determinations of DNA copy number variations during S phase obtained using either high-density oligonucleotide tiling arrays or massively-parallel sequencing to produce replication timing profiles. We show that in untransformed human cells, timing of replication is highly regulated and highly synchronous, and that many genomic segments are replicated in temporal transition regions devoid of initiation where replication forks progress unidirectionally from origins that can be hundreds of kilobases away. Absence of initiation in one transition region is shown at the molecular level by SMARD analysis. Comparison of ES and erythroid cells replication patterns revealed that these cells replicate about 20% of their genome in different quarter of S phase and that ES cells replicate a larger proportion of their genome in early S phase than erythroid cells. Importantly, we detected a strong inverse relationship between timing of replication and distance to the closest expressed gene. This relationship can be used to predict tissue specific timing of replication profiles from expression data and genomic annotations. We also provide evidence that early origins of replication are preferentially located near highly expressed genes, that mid firing origins are located near moderately expressed genes and that late firing origins are located far from genes.
Predictable dynamic program of timing of DNA replication in human cells.
Specimen part
View SamplesThe comparative advantages of RNA-Seq and microarrays in transcriptome profiling were evaluated in the context of a comprehensive study design. Gene expression data from Illumina RNA-Seq and Affymetrix microarrays were obtained from livers of rats exposed to 27 agents that comprised of seven modes of action (MOAs); they were split into training and test sets and verified with real time PCR. Overall design: 105 samples were selected from the DrugMatirx tissue/RNA bank that is now owned by the National Toxicology Program (NTP). The samples were split into 2 sets, training and test, to allow for the evaluation of classifiers derived from the data. There were 63 samples in the training set and 42 in the test set. Of the 63 samples in the training set 45 were derived from rats treated with test agent and 18 were control samples (3 sets of 6). 39 of the test set samples were derived from test agent treated animals and 6 were from vehicle and route matched controls. Five MOAs were represented in the training set and 4 MOAs were in the test set. Two of the MOAs were duplicated from the test set and two were without representation in the training set. For each test agent there were three rats treated, in accordance with the common practice in the field of toxicology. For each MOA there were three representative test agents to ensure adequate power for detecting the MOA signatures. 6 samples from the training set had duplicate libraries sequenced and duplicate sequencing runs for the first library. DrugMatrix, National Toxicology program (NTP) Sequencing was carried out in Dr. Charles Wang's Functional Genomics Core at City of Hope Comprehensive Cancer Center, Duarte, CA
Transcriptomic profiling of rat liver samples in a comprehensive study design by RNA-Seq.
No sample metadata fields
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