We carried out a microarray experiment by using Affymetrix Arabidopsis ATH1 Genechips in order to identify genes that show reduced expression in ros1-1 plants.
The DNA glycosylase/lyase ROS1 functions in pruning DNA methylation patterns in Arabidopsis.
Specimen part
View SamplesLarge-scale cancer genomics projects are profiling hundreds of tumors at multiple molecular layers, including copy number, mRNA and miRNA expression, but the mechanistic relationships between these layers are often excluded from computational models. We developed a supervised learning framework for integrating molecular profiles with regulatory sequence information to reveal regulatory programs in cancer, including miRNA-mediated regulation. We applied our approach to 320 glioblastoma profiles and identified key miRNAs and transcription factors as common or subtype-specific drivers of expression changes. We confirmed that predicted gene expression signatures for proneural subtype regulators were consistent with in vivo expression changes in a PDGF-driven mouse model. We tested two predicted proneural drivers, miR-124 and miR-132, both underexpressed in proneural tumors, by overexpression in neurospheres and observed a partial reversal of corresponding tumor expression changes. Computationally dissecting the role of miRNAs in cancer may ultimately lead to small RNA therapeutics tailored to subtype or individual.
Inferring transcriptional and microRNA-mediated regulatory programs in glioblastoma.
Cell line
View SamplesWe have previously demonstrated older skin exhibits increased sterile inflammation 6 hours after saline-injection. In this work, we examined whether p38MAPK inhibitor in vivo would attenuate this non-specific inflammatory response towards saline in elder individuals (=65 years). Overall design: Skin mRNA profiles 6 hours after saline injection were studied before and after losmapimod treatment.
Enhancement of cutaneous immunity during aging by blocking p38 mitogen-activated protein (MAP) kinase-induced inflammation.
Specimen part, Treatment, Subject
View SamplesThis study sought to provide a novel ex vivo model for analyzing healing kinetics and gene expression of primary human gingival fibroblasts (hGF) within collagen scaffolds.
Cell population kinetics of collagen scaffolds in ex vivo oral wound repair.
Specimen part
View SamplesSensory functions of the vagus nerve are critical for specific aware perceptions and for monitoring visceral functions in the cardio-pulmonary and gastrointestinal systems. Here we present a comprehensive identification, classification, and validation of the neuron types in the neural crest (jugular) and placode (nodose) derived vagal ganglia by single cell transcriptomic (scRNA-seq) analysis. Our results reveal major differences between neurons derived from different embryonic origins. Jugular neurons exhibit fundamental similarities to the somatosensory spinal neurons, including major types such as C-low threshold mechanoreceptors (C-LTMRs), A-LTMRs, Ad-nociceptors, cold-, and mechano-heat C-nociceptors. In contrast, the nodose ganglion contains 18 distinct types dedicated to surveying the physiological state of the internal body. Our results reveal a vast diversity of vagal neuron types including many previously unanticipated types as well as proposed types that are consistent with chemoreceptors, nutrient detectors, baroreceptors, and stretch and volume mechanoreceptors of the respiratory, gastrointestinal, and cardiovascular systems. Overall design: Single-cell RNA-seq from 1896 vagal ganglion cells derived from wild-type and Vglut2Cre-Tomato animals originating from four replicates and consisting of the neuronal and non-neuronal cells that make up the ganglionic tissue.
An Atlas of Vagal Sensory Neurons and Their Molecular Specialization.
Age, Specimen part, Cell line, Subject
View SamplesLineage specific transcription factors (TF) define and reinforce tissue specific cell types. For instance, stable endoderm progenitors were established from human ESC by constitutive expression of SOX7 or SOX17. We hypothesized that combinatorial expression of OCT4, SOX2 and KLF4together with the neural-lineage TF, Zic3, could directly convert fibroblasts into stable neuronal progenitor cells (NPC). Ensuing colonies predominantly expressed genes present in human NPC, as demonstrated by genome wide transcriptional analysis, and this phenotype could be maintained through many passages. When injected in immunodeficient mice, Zic3-induced (Zi)NPC form neuroendocrine tumors without evidence of mesoderm or endoderm. In vitro, ZiNPC spontaneously differentiated to neural cells only, and could be differentiated into astrocytes, oligodendrocytes and motor neuron lineages. In conclusion, addition of Zic3 during induced pluripotent stem cell (iPSC) generation, allows for the derivation of stable neural lineage progenitor cells.
Zic3 induces conversion of human fibroblasts to stable neural progenitor-like cells.
Sex, Specimen part, Disease, Cell line, Treatment
View SamplesThe specific ablation of Rb1 gene in stratified epithelia (RbF/F;K14cre) promotes proliferation and altered differentiation but is insufficient to produce spontaneous tumors. The pRb relative, p107, compensates some of the functions of pRb in these tissues, however RbF/F;K14cre;p107-/- mice die postnatally. Acute pRb loss in stratified epithelia, using an inducible mouse model (RbF/F;K14creERTM), shows that p107 exerts specific tumor suppressor functions in its absence. After simultaneous absence of pRb and p107, p53 transcriptional function is impaired and Pten expression is reduced. All mutant mice develop spontaneous squamous tumors carcinomas rapidly. Gene expression analysis of mouse tumors, besides supporting the impaired p53 function and the susceptibility to Akt/mTOR inhibitors, also revealed significant overlap with human squamous carcinomas. Thus, RbF/F;K14creERTM;p107-/- may constitute a new mouse model for these malignancies. Collectively, these data demonstrate the existence of a previously unreported functional connection between pRb, Pten and p53 tumor suppressors, through p107, of a particular relevance in squamous tumor development.
A novel tumor suppressor network in squamous malignancies.
Specimen part
View SamplesDuring cortical development, distinct subtypes of glutamatergic neurons are sequentially born and differentiate from dynamic populations of progenitors. How progenitors and their daughter cells are temporally patterned remains unknown. Here, we trace the transcriptional trajectories of successive generations of apical progenitors (APs) and isochronic cohorts of their daughter neurons in the developing mouse neocortex using high temporal resolution parallel single-cell RNA sequencing. We identify and functionally characterize a core set of evolutionarily-conserved temporally patterned genes which drive APs from internally-driven states to more exteroceptive states, revealing a progressively increasing role for extracellular signals as corticogenesis unfolds. These embryonic age-dependent AP molecular states are reflected in their neuronal progeny as successive ground states, onto which essentially conserved early post-mitotic differentiation programs are applied. Thus, temporally unfolding molecular birthmarks present in progenitors act in their post-mitotic progeny as seeds for adult neuronal diversity. Overall design: Investigation of the transcriptional dynamics in time-locked cohorts of cortical cells across embryonic neurogenesis. Flashtag is injected at 4 ages (E12, E13, E14, E15), and cells collected 1H, 24H, 96H after birth (= a total of 12 conditions) and analyzed by single cell transcriptomics.
Temporal patterning of apical progenitors and their daughter neurons in the developing neocortex.
Subject
View SamplesEndothelial cells (EC) lining arteries and veins have distinct molecular and functional signatures. The (epi)genetic regulatory mechanisms underlying this heterogeneity in human EC are incompletely understood. Using genome-wide microarray screening we established a specific fingerprint of freshly isolated arterial (HUAEC) and venous EC (HUVEC) from human umbilical cord comprising 64 arterial and 12 venous genes, representing distinct functions and pathways. Among the arterial genes were 8 transcription factors, including HEY2, a downstream target of Notch signaling and the current golden standard pathway for arterial EC specification. Short-term culture of HUAEC or HUVEC abrogated differential gene expression resulting in a default state. Erasure of arterial gene expression was at least in part due to loss of canonical Notch activity and HEY2 expression. Notably, nCounter analysis revealed that restoring HEY2 expression or Delta-like 4 (Dll4)-induced Notch signaling in cultured HUVEC or HUAEC only partially reinstated the arterial EC gene signature while combined overexpression of the 8 transcription factors restored this fingerprint much more robustly. Each transcription factor had a different impact on gene regulation, with some stimulating only few and others boosting a large proportion of arterial genes. Interestingly, although there was some overlap and cross-regulation, the transcription factors largely complemented each other in regulating the arterial EC gene profile. Thus, our study showed that Notch signaling determines only part of the arterial EC signature and identified additional novel and complementary transcriptional players in the complex regulation of human arteriovenous EC identity
Unraveling a novel transcription factor code determining the human arterial-specific endothelial cell signature.
Specimen part
View SamplesHistone deacetylase (HDAC) inhibitors are widely utilized in hematopoietic malignance therapy; nevertheless, little is currently known concerning their effects on normal myelopoiesis. In order to investigate a putative interference of HDAC inhibitors in myeloid commitment of hematopoietic stem/progenitor cells (HSPCs) we treated CD34+ cells with valproic acid (VPA). Moreover, we investigate changes in gene expression induced by VPA treatment on HSPCs, by means of microarray analysis in VPA treated and untreated (CTR) CD34+ cells.
Valproic acid triggers erythro/megakaryocyte lineage decision through induction of GFI1B and MLLT3 expression.
Specimen part, Treatment
View Samples