Polyoma virus nephropathy (PVAN) is a common cause of kidney allograft dysfunction and loss. Microscopic descriptions of PVAN are very similar to T-cell mediated rejection (TCMR) and have unclear underlying molecular mechanisms. To identify PVAN-specific gene expression, we analyzed 162 kidney biopsies with and without PVAN for global gene expression. Unsupervised hierarchical clustering analysis of all 162 biopsies revealed high similarity between PVAN and TCMR gene expression. Increasing the stringency for the specificity (p <0.001 and >2-fold expression) between PVAN and TCMR, 158 and 252 unique PVAN and TCMR injury-specific probesets were observed, respectively. While TCMR-specific probeset were overwhelmingly involved in immune response costimulation (CTLA4, CD28, CD86) and TCR (NFATC2, LCP2) signaling, PVAN-specific probesets were mainly related to viral replication process (IFITM1, LTF, NOSIP, RARRES3), RNA polymerase assembly (POLR2l, TAF10, RPS15) and pathogen recognition receptors (C1QA, C3, CFD). A principal component analysis using these genes further confirmed the most optimal separation between the 3 different clinical phenotypes. Validation of 4 PVAN-specific probesets (RPS15, CFD, LTF, and NOSIP) by QPCR and further confirmation by IHC of 2 PVAN-specific proteins with anti-viral function (LTF and IFITM1) was done, showing significantly higher expression within interstitial cellular infiltrates and in tubuli in PVAN specimens as compared to TCMR and NL kidney biopsies. In conclusion, even though PVAN and TCMR kidney allografts share great similarities on gene perturbation, particular PVAN-specific transcripts were identified with well-known anti-viral properties that provide tools for discerning PVAN and AR as well as attractive targets for rational drug design.
Intragraft Antiviral-Specific Gene Expression as a Distinctive Transcriptional Signature for Studies in Polyomavirus-Associated Nephropathy.
Specimen part, Disease
View SamplesUsing meta-analysis of eight independent transplant datasets (236 graft biopsy samples) from four organs, we identified a common rejection module (CRM) consisting of 11 genes that were significantly overexpressed in acute rejection (AR) across all transplanted organs. The CRM genes could diagnose AR with high specificity and sensitivity in three additional independent cohorts (794 samples). In another two independent cohorts (151 renal transplant biopsies), the CRM genes correlated with the extent of graft injury and predicted future injury to a graft using protocol biopsies. Inferred drug mechanisms from the literature suggested that two FDA-approved drugs (atorvastatin and dasatinib), approved for non-transplant indications, could regulate specific CRM genes and reduce the number of graft infiltrating cells during acute rejection. We treated mice with HLA-mismatched murine cardiac transplant with atorvastatin and dasatinib and showed reduction of the CRM genes, significant reduction of graft infiltrating cells, and extended graft survival. We further validated the beneficial effect of atorvastatina on graft survival by retrospective analysis of electronic medical records of a single-center cohort of 2,515 renal transplant patients. In conclusion, we identified a CRM in transplantation that provides new opportunities for diagnosis, drug repositioning and rational drug design.
A common rejection module (CRM) for acute rejection across multiple organs identifies novel therapeutics for organ transplantation.
Specimen part
View SamplesWe examined global gene expression patterns in response to PGC-1 expression in cells derived from liver or muscle.
Direct link between metabolic regulation and the heat-shock response through the transcriptional regulator PGC-1α.
Specimen part
View SamplesCell adhesion plays an important role in determining cell shape and function in a variety of physiological and pathophysiological conditions. While links between metabolism and cell adhesion were previously suggested, the exact context and molecular details of such a cross-talk remain incompletely understood.
Inhibition of Adhesion Molecule Gene Expression and Cell Adhesion by the Metabolic Regulator PGC-1α.
Specimen part, Cell line
View SamplesSecreted proteins serve pivotal roles in the development of multicellular organisms, acting as structural matrix, extracellular enzymes and signal molecules. In this study we demonstrate, unexpectedly, that PGC-1, a critical transcriptional co-activator of metabolic gene expression, functions to down-regulate expression of diverse genes encoding secreted molecules and extracellular matrix (ECM) components to modulate the secretome. We show that both endogenous and exogenous PGC-1 down-regulate expression of numerous genes encoding secreted molecules. Mechanistically, results obtained using mRNA stability measurements as well as intronic RNA expression analysis are consistent with a transcriptional effect of PGC-1 on expression of genes encoding secreted proteins. Interestingly, PGC-1 requires the central heat shock response regulator HSF1 to affect some of its targets, and both factors co-reside on several target genes encoding secreted molecules in cells. Finally, using a mass spectrometric analysis of secreted proteins, we demonstrate that PGC-1 modulates the secretome of mouse embryonic fibroblasts (MEFs).
Control of Secreted Protein Gene Expression and the Mammalian Secretome by the Metabolic Regulator PGC-1α.
Specimen part
View SamplesRetinitis Pigmentosa (RP) is a progressive retinal degeneration in which the retina loses nearly all of its photoreceptor cells and undergoes major structural changes. Little is known regarding the role the resident glia, the Mller glia, play in the progression of the disease. Here we define gene expression changes in Mller glial cells (MGCs) from two different mouse models of RP, the retinal degeneration 1 (rd1) and rhodopsin knock-out (Rhod-ko) models. The RNA repertoire of 28 single MGCs was comprehensively profiled, and a comparison was made between MGC from wild type (WT) and mutant retinas. Two time points were chosen for analysis, one at the peak of rod photoreceptor death and one during the period of cone photoreceptor death. MGCs have been shown to respond to retinal degeneration by undergoing gliosis, a process marked by the upregulation of GFAP. In this data, many additional transcripts were found to change. These can be placed into functional clusters, such as retinal remodeling, stress response, and immune related response. It is noteworthy that a high degree of heterogeneity among the individual cells was observed, possibly due to their different spatial proximities to dying cells, and/or inherent heterogeneity among MGCs.
Gene expression changes within Müller glial cells in retinitis pigmentosa.
Specimen part
View SamplesIncreasing evidence suggests that linker histone H1 can influence distinct cellular processes by acting as a gene-specific regulator. However, the mechanistic basis underlying such H1 specificity and whether H1 acts in concert with other chromatin-altering activities remain unclear. To investigate the cooperative role of H1.2, Cul4A and PAF1 on gene regulation, genome-wide gene expression analysis is carried out in 293T cells expressing control shRNA, H1.2 shRNA, Cul4A shRNA or PAF1 shRNA.
Linker Histone H1.2 cooperates with Cul4A and PAF1 to drive H4K31 ubiquitylation-mediated transactivation.
Cell line
View SamplesUsing microarrays to genotype the parental origin of progeny resulting from a cross between S96 and YJM789 yeast strains, we mapped the distribution of crossovers that occurred during meiosis. Knowledge of the crossover distribution allowed us to assess changes in crossover control in wild type and mutant strains.
Global analysis of the meiotic crossover landscape.
No sample metadata fields
View SamplesEnriched tumor epithelium from 61 primary and metastasis tumor specimens was obtained by laser capture microdissection (LCM) as previously described (Boersma et al., 2007). In brief, frozen 8-m serial sections from OCT-preserved frozen tissues were prepared and mounted on plain, uncharged microscope slides. One Hematoxylin/eosin-stained section of each specimen was reviewed by a pathologist to confirm diagnosis and presence of tumor. The pathologist indicated which representative sections of the tumors should be microdissected. LCM was performed with the Pixcell II LCM system (Arcturus, Mountain View, CA). Total RNA was isolated using the PicoPure protocol (Arcturus, Mountain View, CA). The mRNA was amplified with two linear amplification steps by in vitro transcription using the MEGAscript T7 kit (Ambion, Austin, TX) followed by the labeling step using the BioArray HighYield RNA Transcript Labeling Kit T3 from Enzo Life Sciences (Farmingdale, NY). Labeled cRNA was hybridized onto Affymetix GeneChip HG-U133 Plus 2.0 Arrays.
Integrative genomic and transcriptomic characterization of matched primary and metastatic liver and colorectal carcinoma.
Specimen part, Disease, Disease stage
View SamplesThe AML1-ETO fusion protein, a transcription factor generated by the t(8;21) translocation in acute myeloid leukaemia (AML), dictates a leukemic program by increasing self-renewal and inhibiting differentiation. Here we demonstrate that the histone demethylase JMJD1C functions as a co-activator for AML1-ETO and is required for its transcriptional program. JMJD1C is directly recruited by AML1-ETO to its target genes and regulates their expression by maintaining low H3K9me2 levels. Analyses in JMJD1C knockout mice also establish a JMJD1C requirement for AML1-ETO’s ability to increase proliferation. We also show a critical role for JMJD1C in the survival of multiple human AML cell lines, suggesting that it is required for leukemic programs in different AML cell types through its association with key transcription factors. Overall design: Examination of RNA expression when Kasumi-1 cells are treated with control shRNA or two different JMJD1C shRNAs; in duplicate. Please note that the ''shAML1_ETO_vs_shControl.all_gene_exp.tb.txtl'' was generated comparing control and shRNA treated RNA abundance-using previously published data [GSE43834; GSM1071857 and GSM1071852].
JMJD1C is required for the survival of acute myeloid leukemia by functioning as a coactivator for key transcription factors.
No sample metadata fields
View Samples