Purpose: The ability to rationally manipulate the transcriptional states of cells would be of great use in medicine and bioengineering. We have developed a novel algorithm, NetSurgeon, which utilizes genome-wide gene regulatory networks to identify interventions that force a cell toward a desired expression state. Results: We used NetSurgeon to select transcription factor deletions aimed at improving ethanol production in S. cerevisiae cultures that are catabolizing xylose. We reasoned that interventions that move the transcriptional states of cells utilizing xylose toward the fermentative state typical of cells that are producing ethanol rapidly (while utilizing glucose) might improve xylose fermentation. Some of the interventions selected by NetSurgeon successfully promoted a fermentative transcriptional state in the absence of glucose, resulting in strains with a 2.7-fold increase in xylose import rates, a 4-fold improvement in xylose integration into central carbon metabolism, or a 1.3-fold increase in ethanol production rate. Conclusions: We conclude by presenting an integrated model of transcriptional regulation and metabolic flux that will enable future metabolic engineering efforts aimed at improving xylose fermentation to prioritize functional regulators of central carbon metabolism. Overall design: Mutant and wildtype S. cerevisiae cells were put into 48 hour aerobic batch fermentations of synthetic complete medium supplmented with 2% glucose and 5% xylose and culture samples were taken at 4 hours and 24 hours for transcriptional profiling performed by RNA-Seq analysis. In addition, wildtype S. cerevisiae cells were grown in various single carbon sources for 12 hours and culture samples were taken for transcriptional profiling performed by RNA-Seq analysis.
Model-based transcriptome engineering promotes a fermentative transcriptional state in yeast.
Subject
View SamplesIn 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.
No sample metadata fields
View SamplesWe recently demonstrated mitochondrial degenerations precede muscle wasting in time course progression of CC. However, the extent of muscle perturbations prior to wasting in CC is unknown. Therefore, we performed global gene expression analysis in CC-induced muscle wasting to enhance understanding of intramuscular perturbations across the development of CC. Overall design: Lewis Lung Carcinoma (LLC) was injected into the hind-flank of C57BL6/J mice at 8 wks age with tumor allowed to develop for 1, 2, 3, or 4 wks and compared to PBS injected control. Muscle wasting was evident at 4 wks LLC. Animals were anesthetized using isoflourane and gastrocnemius muscles were collected for analysis. Conclusions: Current findings present novel evidence of transcriptomic shifts and altered cellular pathways in CC-induced muscle wasting.
Transcriptomic analysis of the development of skeletal muscle atrophy in cancer-cachexia in tumor-bearing mice.
Specimen part, Cell line, Subject
View SamplesTumor samples were obtained from patients with stage II-III breast cancer before starting neoadjuvant chemotherapy with four cycles of 5-fluorouracil/epirubicin/cyclophosphamide (FEC) followed by four cycles of docetaxel/capecitabine (TX) on US Oncology clinical trial 02-103. Most patients with HER-2-positive cancer also received trastuzumab (H).
Cell line derived multi-gene predictor of pathologic response to neoadjuvant chemotherapy in breast cancer: a validation study on US Oncology 02-103 clinical trial.
Age
View SamplesSoybean plants that do not produce a sink, such as depodded or male sterile plants, exhibit physiological and morphological changes during the reproductive stages, including increased levels of nitrogen and starch in the leaves and a delayed senescence. To identify transcriptional changes that occur in leaves of sink-limited plants, we used RNAseq to compare gene expression levels in trifoliate leaves from depodded and ms6 male sterile plants and control plants. In sink-limited tissues, we observed a deferral of the expression of senescence-associated genes and a continued high expression of genes associated with the maturity phase of leaf development. We identified GO-terms associated with growth and development and storage protein in sink limited tissues. We also identified that the bHLH. ARFs, and SBP transcription factors were expressed in sink limited tissues while the senescing control leaves expressed WRKY and NAC transcription factors. We identified genes that were not expressed during normal leaf development but highly expressed in sink-limited plants, including the D4 “non-yellowing” gene. These changes highlighted several metabolic pathways that were involved in distinct modes of resource parttioning in the “stay green” leaves. Overall design: Timecourse gene expression analysis of sink-limited soybean leaves. Gene expression was profiled from R2 growth stage (flowering) until the onset of leaf seenscence, and contrasted between mechanically and genetically sink-limited soybeans.
Transcriptional profiling of mechanically and genetically sink-limited soybeans.
Specimen part, Subject, Time
View SamplesWe use RNA sequencing technology in a time course study to measure transcript abundance from three developmental stages in cotyledons and five stages in the trifoliate leaf of Glycine max to identify genes with distinct temporal patterns of expression during leaf or cotyledon development. We also examine the diffrences between these two photosynthetic tissues. Overall design: Timecourse Expression analysis of Cotyledon Development and Leaf Development using RNAseq on distinct timepoints. 3 stages of the cotyledon were sequenced with 3 biological replicates in each stage. Five stages of the leaf were sequenced with 3 biological replicates for each stage.
Developmental profiling of gene expression in soybean trifoliate leaves and cotyledons.
Specimen part, Subject
View SamplesRNA-sequencing of young and old mouse eyelids identified a number of signaling pathways, including FGF and Wnt that were altered in meibomian glands and conjunctiva of aging mice. Overall design: RNA isolated from frozen eyelid tissue excised from young and old mice was sequenced using an Illumina HiSeq 2500.
Transcriptome analysis of aging mouse meibomian glands.
Sex, Age, Specimen part, Cell line, Subject
View SamplesWhile infection of chickens with highly pathogenic avian influenza (HPAI) H5N1 subtypes often leads to complete mortality within 24 to 48 h, infection of ducks in contrast causes mild or no clinical signs. Rapid onsets of fatal disease in chickens, but with no evidence of severe clinical symptoms in ducks, suggest underlying differences in their innate immune mechanisms. To understand the molecular basis for such difference, chicken and duck primary lung cells, infected with a low-pathogenicity avian influenza (LPAI) and two HPAI H5N1 viruses, were subjected to RNA expression profiling using Affymetrix Chicken GeneChip arrays.
Highly pathogenic avian influenza virus infection in chickens but not ducks is associated with elevated host immune and pro-inflammatory responses.
Age, Specimen part, Treatment
View SamplesThe goal of the microarray analysis is to determine the redundant and distinct roles of Dhh and Ihh in ovarian functions
Reproductive, Physiological, and Molecular Outcomes in Female Mice Deficient in Dhh and Ihh.
Age, Specimen part
View SamplesTo generate an unbiased view of changes to the retinal gene network in Neurog2 retinal mutants, we generated and compared the P2 transcriptomes from control, heterozygote and mutant mice. A pair of P2 retinas from each biologic replicate were used to produce libraries for high throughput sequencing (n = 5 biologic replicates/genotype). Reads were aligned with BWA and Bowtie programs to the mm10 genome. Aligned reads were then analyzed for differentially expressed transcripts using the CuffDiff program in the Galaxy online bioinformatics package (www.usegalaxy.org). Overall design: Total RNA from Neurog2CKO/CKO(wildtype; n = 5), Chx10Cre;Neurog2CKO/+(heterozygote; n = 5), and Chx10Cre;Neurog2CKO/CKO(mutant; n = 5) P2 retinas.
Requirements for Neurogenin2 during mouse postnatal retinal neurogenesis.
Specimen part, Cell line, Subject
View Samples