This experiment is designed to study the effects to HMPV on A549 over time
Identification of human metapneumovirus-induced gene networks in airway epithelial cells by microarray analysis.
No sample metadata fields
View SamplesTranscription factor (TF)-induced reprogramming of somatic cells into induced pluripotent stem cells (iPSC) is associated with genome-wide changes in chromatin modifications. Polycomb-mediated histone H3 lysine-27 trimethylation (H3K27me3) has been proposed as a defining mark that distinguishes the somatic from the iPSC epigenome. Here, we dissected the functional role of H3K27me3 in TF-induced reprogramming through the inactivation of the H3K27 methylase EZH2 at the onset of reprogramming. Our results demonstrate that surprisingly the establishment of functional iPSC proceeds despite global loss of H3K27me3. iPSC lacking EZH2 efficiently silenced the somatic transcriptome and differentiated into tissues derived from the three germ layers. Remarkably, the genome-wide analysis of H3K27me3 in Ezh2 mutant iPSC cells revealed the retention of this mark on a highly selected group of Polycomb targets enriched for developmental regulators controlling the expression of lineage specific genes. Erasure of H3K27me3 from these targets led to a striking impairment in TF-induced reprogramming. These results indicate that PRC2-mediated H3K27 trimethylation is required on a highly selective core of Polycomb targets whose repression enables TF-dependent cell reprogramming.
Cell reprogramming requires silencing of a core subset of polycomb targets.
Specimen part
View SamplesB cells are indispensable for humoral immunity, as they ultimately give rise to antibody-secreting plasma cells. During T cell-dependent antibody responses, naive B cells form germinal centers (GCs), a distinct histologic structure found in secondary lymphoid organs. Naive B cells become activated upon interaction with T cells and antigen presenting cells, and begin to rapidly proliferate and form the characteristic GC structure.
The LRF transcription factor regulates mature B cell development and the germinal center response in mice.
Age, Specimen part
View SamplesPolycomb proteins control proliferation and cellular transformation regulating DNA replication independently of cell cycle checkpoints
Polycomb proteins control proliferation and transformation independently of cell cycle checkpoints by regulating DNA replication.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The B-cell receptor controls fitness of MYC-driven lymphoma cells via GSK3β inhibition.
No sample metadata fields
View SamplesSimilar to resting mature B cells, where the B-cell antigen receptor (BCR) is essential for cellular survival, surface BCR expression is conserved in most mature B cell lymphomas. The identification of activating BCR mutations and the growth disadvantage upon BCR knockdown of cells of certain lymphoma entities has led to the view that BCR signaling is required for tumour cell survival. Consequently, the BCR signaling machinery has become a new target in the therapy of B cell malignancies. Here, we studied the effects of BCR ablation on MYC-driven mouse B cell lymphomas and compared them to observations in human Burkitt lymphoma. Whereas BCR ablation did not, per se, significantly affect lymphoma growth, BCR-negative (BCR-) tumour cells rapidly disappeared in the presence of their BCR-expressing (BCR+) counterparts in vitro and in vivo. This required neither cellular contact, nor factors released by BCR+ tumour cells. Instead, BCR loss induced the rewiring of central carbon metabolism increasing the sensitivity of receptor-less lymphoma cells to nutrient restriction. The BCR attenuated GSK3 activity to support MYC-controlled gene expression. BCR- tumour cells exhibited increased GSK3 activity and were rescued from their competitive growth disadvantage by GSK3. BCR-negative lymphoma variants that restored competitive fitness, normalized GSK3 following constitutive activation of the MAPK pathway, commonly through Ras mutations. Similarly, in Burkitt lymphoma, activating RAS mutations may propagate Ig-crippled tumour cells, which usually represent a minority of the tumour bulk. Thus, while BCR expression enhances lymphoma cell fitness, BCR-targeted therapies may profit from combinations with drugs targeting BCR-less tumour cells.
The B-cell receptor controls fitness of MYC-driven lymphoma cells via GSK3β inhibition.
No sample metadata fields
View SamplesHeat stress is one of the most prominent and deleterious environmental threads affecting plant growth and development. Upon high temperatures, plants launch specialized gene expression programs that promote stress protection and survival. These programs involve global and specific changes at the transcriptional and translational levels. However the coordination of these processes and their specific role in the establishment of the heat stress response is not fully elucidated.
Analysis of genome-wide changes in the translatome of Arabidopsis seedlings subjected to heat stress.
Specimen part
View SamplesMicroarray was used to identify differential gene expression pattern in Barrett's esophagus (BE), compared to the normal adjacent epithelia gastric cardia (GC) and normal squamous esophagus (NE)
Evidence for a functional role of epigenetically regulated midcluster HOXB genes in the development of Barrett esophagus.
Specimen part
View SamplesUV-B radiation affects leaf growth in a wide range of species. In this work, we demonstrate that UV-B levels present in solar radiation inhibits maize leaf growth without causing any other visible stress symptoms, including accumulation of DNA damage. We conducted kinematic analyses of cell division and expansion to understand the impact of UV-B radiation on these cellular processes. Our results demonstrate that the decrease in leaf growth is a consequence of a reduction in cell production, and a shortened growth zone (GZ) in UV-B irradiated leaves. To determine the molecular pathways involved in UV-B inhibition of leaf growth, we performed RNA sequencing on isolated GZ tissues of control and UV-B exposed plants. Our results show a link between the observed leaf growth inhibition and the expression of specific cell cycle and developmental genes, including Growth Regulating Factors (GRFs) and transcripts for proteins participating in different hormone pathways. Overall design: Factorial design with two factors: Treatment (control vs UV-B) x Zone I (0-1cm from base of the leaf), 2 (1-2cm from base of the leaf) and 3 (2-3cm from base of the leaf), 3 replicates
UV-B Inhibits Leaf Growth through Changes in Growth Regulating Factors and Gibberellin Levels.
Specimen part, Subject
View SamplesCD1d expression by thymocytes is required to select iNKT cells. When CD1d is expressed only on thymocytes (pLck-CD1d tg mice), iNKT cells are hyperresponsive to antigen stimulation suggesting that, in physiological conditions, these cells undergo functional education mediated by additional CD1d-expressing cells. Here, we investigated the mechanisms of this functional education. We find that peripheral iNKT cells from pLck-CD1d tg mice express significantly less SHP-1, a tyrosine phosphatase negatively regulating TCR signaling, than WT cells. iNKT cells from heterozygous SHP-1-mutated motheaten mice, displaying similar SHP-1 reduction as pLck-CD1d tg iNKT cells, are antigen-hyperresponsive. Restoring normal CD1d expression in pLck-CD1d tg mice normalizes SHP-1 expression and responsiveness of iNKT cells. In WT mice, iNKT cells upregulate SHP-1 and decrease responsiveness upon emigration from thymus to periphery. This depends on contacts with CD1d-expressing DCs. iNKT cell functional education is therefore controlled by DCs via tuning SHP-1 expression level in the periphery.
Functional education of invariant NKT cells by dendritic cell tuning of SHP-1.
Age, Specimen part, Treatment
View Samples