Histone H3K4 methylation is connected to gene transcription from yeast to humans, but its mechanistic role in transcription and chromatin dynamics remains poorly understood. Here, we investigated the functions for Set1 and Jhd2, the sole H3K4 methyltransferase and H3K4 demethylase, respectively, in S. cerevisiae. Our data show that Set1 and Jhd2 predominantly co-regulate transcription. To further understand the role for H3K4 methylation, we overexpressed Flag epitope-tagged SET1-G990E (a dominant hyperactive allele of SET1) in yeast using the constitutive ADH1 promoter (ADH1p). As a control, we also overexpressed Flag epitope-tagged wild type SET1 in yeast. Analysis of gene expression in set1-null, jhd2-null and wild type SET1 or hypeactive SET1-G990E overexpressing mutants together revealed that the transcriptional regulation at a sub-set of genes, inclduing those governing glycogen metabolism and ribosome biogenesis, is highly sensitive to any change (i.e., loss or gain) in H3K4 methylation levels. Overall, we find combined activities of Set1 and Jhd2 via dynamic modulation of H3K4 methylation contribute to positive or negative transcriptional regulation at shared target genes. Overall design: Gene expression changes were generated from five different yeast strains representing wild type control, set1 null and jhd2 null mutants, and wild type SET1 or dominant hyperacive SET1-G990E overexpressing mutants. Three independent biological samples were grown for each strain, total RNA was isolated, libraries were prepared, sequenced, and analyzed separately.
Counteracting H3K4 methylation modulators Set1 and Jhd2 co-regulate chromatin dynamics and gene transcription.
Cell line, Subject
View SamplesGraft-versus-host disease (GVHD) is the most serious complication of allogeneic hematopoietic cell transplantation. Notch signals delivered during the first 48 hours after transplantation drive proinflammatory cytokine production in conventional T cells (Tconv) and inhibit expansion of regulatory T cells (Tregs). Short-term Notch inhibition induces long-term GVHD protection. However, it remains unknown whether Notch blockade blunts GVHD through its effects on Tconv, Tregs, or both, and what early Notch-regulated molecular events occur in alloantigen-specific T cells. To address these questions, we engineered T cell grafts to achieve selective Notch blockade in Tconv vs. Tregs and evaluated their capacity to trigger GVHD in mice. Notch blockade in Tconv was essential for GVHD protection, as GVHD severity was similar in recipients of wild-type Tconv combined with Notch-deprived vs. wild-type Tregs. To identify the impact of Notch signaling on the earliest steps of T cell activation in vivo, we established a new acute GVHD model mediated by clonal alloantigen-specific 4C CD4+ Tconv. Notch-deprived 4C T cells had preserved early steps of activation, IL-2 production, proliferation, and T helper polarization. In contrast, Notch inhibition dampened IFN-? and IL-17 production, diminished mTORC1 and ERK1/2 activation, and impaired transcription of a subset of Myc-regulated genes. The distinct Notch-regulated signature had minimal overlap with known Notch targets in T cell leukemia and developing T cells, highlighting the specific impact of Notch signaling in mature T cells. Our findings uncover a unique molecular program associated with pathogenic effects of Notch in T cells at the earliest stages of GVHD. Overall design: 4 samples per cohort (Notch blockade using Dll1/4 neutralizing antibodies vs isotype control antibodies - GD) were analyzed. Additional 4 samples contained 4C T cells retrieved from syngeneic recipients.
Early Notch Signals Induce a Pathogenic Molecular Signature during Priming of Alloantigen-Specific Conventional CD4<sup>+</sup> T Cells in Graft-versus-Host Disease.
Specimen part, Cell line, Treatment, Subject
View SamplesAnalysis of baseline gene expression in bone marrow derived dendritic cells (BMDC) from female CBA/J (CBA) and C57BL/6 (BL/6) mice. Results provide insight into strain-dependent differences in gene expression.
CD209a expression on dendritic cells is critical for the development of pathogenic Th17 cell responses in murine schistosomiasis.
Specimen part
View SamplesThe severe acute respiratory syndrome (SARS) epidemic was characterized by increased pathogenicity in the elderly due to an early exacerbated innate host response. SARS-CoV is a zoonotic pathogen that entered the human population through an intermediate host like the palm civet. To prevent future introductions of zoonotic SARS-CoV strains and subsequent transmission into the human population, heterologous disease models are needed to test the efficacy of vaccines and therapeutics against both late human and zoonotic isolates. Here we show that both human and zoonotic SARS-CoV strains can infect cynomolgus macaques and resulted in radiological as well as histopathological changes similar to those seen in mild human cases. Viral replication was higher in animals infected with a late human phase isolate compared to a zoonotic isolate. Host responses to the three SARS-CoV strains were similar and only apparent early during infection with the majority of genes associated with interferon signalling pathways.This study characterizes critical disease models in the evaluation and licensure of therapeutic strategies against SARS-CoV for human use
Comparative pathogenesis of three human and zoonotic SARS-CoV strains in cynomolgus macaques.
Specimen part, Time
View SamplesRelatively little is understood about the dynamics of global hostpathogen transcriptome changes that occur during bacterial infection of mucosal surfaces. To test the hypothesis that group A Streptococcus (GAS) infection of the oropharynx provokes a host transcriptome response, we performed genome-wide transcriptome analysis using a nonhuman primate model of experimental pharyngitis. We also identified host and pathogen biological processes and individual host and pathogen gene pairs with correlated patterns of expression, suggesting interaction. For this study, 509 host genes and seven biological pathways were differentially expressed throughout the entire 32-day infection cycle. GAS infection produced an initial widespread significant decrease in expression of many host genes, including those involved in cytokine production, vesicle formation, metabolism, and signal transduction. This repression lasted until day 4, at which time a large increase in expression of host genes was observed, including those involved in protein translation, antigen presentation, and GTP-mediated signaling. The interactome analysis identified 73 host and pathogen gene pairs with correlated expression levels. We discovered significant correlations between transcripts of GAS genes involved in hyaluronic capsule production and host endocytic vesicle formation, GAS GTPases and host fibrinolytic genes, and GAS response to interaction with neutrophils. We also identified a strong signal, suggesting interaction between host T cells and genes in the GAS mevalonic acid synthesis pathway responsible for production of isopentenyl-pyrophosphate, a short-chain phospholipid that stimulates these T cells. Taken together, our Q:2 results are unique in providing a comprehensive understanding of the hostpathogen interactome during mucosal infection by a bacterial pathogen.
Interactome analysis of longitudinal pharyngeal infection of cynomolgus macaques by group A Streptococcus.
Sex, Subject
View SamplesIdentification of intrathymic Eomes+ natural Th1 cells creates a novel idea that there is more than one way for the generation of innate CD4 T cells. To more deeply characterize this type of innate T cells, we compared the gene expression profile between nTh1 cells generated in CIITAtg mice and classic Th1 cells differentiated from naive CD4 T cells in Th1-polarizing condition.
Thymic low affinity/avidity interaction selects natural Th1 cells.
Age, Specimen part
View SamplesMarek’s disease virus 1 (MDV-1), an oncogenic -herpesvirus that induces T-cell lymphomas in chickens, serves as model system to study transformation by lymphotropic herpesviruses. Like the oncogenic human -herpesviruses Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV), MDV-1 encodes several viral microRNAs (miRNAs). One MDV-1 miRNA, miR-M4, shares the same “seed” targeting sequence with both a KSHV miRNA, miR-K11, and cellular miR-155. Importantly, miR-M4 plays a critical role in T-cell transformation by MDV-1, while miR-K11 and cellular miR-155 are thought to play key roles in B-cell transformation by KSHV and EBV, respectively. Here, we present an analysis of the mRNAs targeted by viral miRNAs expressed in the chicken T-cell line MSB1, which is naturally coinfected with MDV-1 and the related nonpathogenic virus MDV-2. Our analysis identified>1,000 endogenous mRNAs targeted by miRNAs encoded by each virus, many of which are targeted by both MDV-1 and MDV-2 miRNAs. We present a functional analysis of an MDV-1 gene, RLORF8, targeted by four MDV-1 miRNAs and a cellular gene, encoding interleukin-18 (IL-18) and targeted by both MDV-1 and MDV-2 miRNAs, and show that ectopic expression of either protein in a form resistant to miRNA inhibition results in inhibition of cell proliferation. Finally, we present a restricted list of 9 genes targeted by not only MDV-1 miR-M4 but also KSHV miR-K11 and human miR-155. Given the critical role played by miR-155 seed family members in lymphomagenesis in humans and chickens, these mRNA targets may contain genes whose inhibition plays a conserved role in herpesvirus transformation. Overall design: PAR-CLIP experiment of MSB1 cells
Analysis of the mRNA targetome of microRNAs expressed by Marek's disease virus.
Specimen part, Cell line, Subject
View SamplesTerahertz (THz) technology has emerged for biomedical applications such as scanning, molecular spectroscopy, and medical imaging. However, the biological effect of THz radiation is not fully understood. Non-thermal effects of THz radiation were investigated by applying a femtosecond-terahertz (fs-THz) pulse to mouse skin. Analysis of the genome-wide expression profile in fs-THz-irradiated skin indicated that wound responses were predominantly through NFB1- and Smad3/4-mediated transcriptional activation. Repeated fs-THz radiation delayed the closure of mouse skin punch wounds due to up-regulation of transforming growth factor-beta (TGF-). These findings suggest that fs-THz radiation provokes a wound-like signal in skin with increased expression of TGF- and activation of its downstream target genes, which perturbs the wound healing process in vivo.
High-power femtosecond-terahertz pulse induces a wound response in mouse skin.
Sex, Specimen part
View SamplesArabipdosis thaliana (ecotype Col-0) was infected with the root pathogen Plasmodiophora brassicae. Gene expression of the host plant has been analyzed at two time points after inoculation (10 and 23 days after inoculation) compared to the correspondend control plants.
Transcriptome analysis of Arabidopsis clubroots indicate a key role for cytokinins in disease development.
Age, Specimen part, Cell line, Time
View SamplesPancreatic islet transplantation as a cure for type 1 diabetes (T1D) cannot be scaled up due to a scarcity of human pancreas donors. In vitro expansion of beta cells from mature human pancreatic islets provides an alternative source of insulin-producing cells. The exact nature of the expanded cells produced by diverse expansion protocols, and their potential for differentiation into functional beta cells, remain elusive. We performed a large-scale meta-analysis of gene expression in human pancreatic islet cells, which were processed using three different previously described protocols for expansion and attempted re-differentiation. All three expansion protocols induced dramatic changes in the expression profiles of pancreatic islets; many of these changes are shared among the three protocols. Attempts at re-differentiation of expanded cells induce a limited number of gene expression changes. Nevertheless, these fail to restore a pancreatic islet-like gene expression pattern. Comparison with a collection of public microarray datasets confirmed that expanded cells are highly comparable to mesenchymal stem cells. Genes induced in expanded cells are also enriched for targets of transcription factors important for pluripotency induction. The present data increases our understanding of the active pathways in expanded and re-differentiated islets. Knowledge of the mesenchymal stem cell potential may help development of drug therapeutics to restore beta cell mass in T1D patients.
Meta-analysis of gene expression in human pancreatic islets after in vitro expansion.
Specimen part
View Samples