Human B-1 cells (CD20+CD27+CD43+CD38lo/int) and pre-plasmablast like cells (CD20+CD27hiCD38hi) are new antibody secreting cells identified in circulation. We used microarray to compare and contrast expressed genes between these two cell population
Distinctions among Circulating Antibody-Secreting Cell Populations, Including B-1 Cells, in Human Adult Peripheral Blood.
Specimen part
View SamplesA transcription factor CYTOKININ-RESPONSIVE GATA FACTOR 1 (CGA1) regulates chloroplast development in rice (Oryza sativa) through modifying the expression of important nuclear expressed, chloroplast localized genes.
Rice cytokinin GATA transcription Factor1 regulates chloroplast development and plant architecture.
Specimen part
View SamplesThe yeast PMR1 (ATP2C1) gene codes for the eukaryotic prototype of a high affinity P-type ATPase required for Ca2+/Mn2+ transport into the Golgi. Cells lacking PMR1 exhibit multiple genetic interactions with genes involved in DNA recombination and replication, a fact that is not yet understood. We find that deletion of PMR1 causes a delay in DNA replication initiation, progression and G2/M transition and induces the transcriptional up-regulation of genes involved in cell cycle regulation, including CLB5 and SWE1. Interestingly, pmr1 clb5 double mutants exhibit a dramatic delay in DNA replication and increased DNA breakage, while endoreplication and the formation of multi-nucleated, giant yeast is observed in pmr1 swe1 cells. Because these phenotypes can be attributed to impeded Mn2+-pump function, we provide a model in which Mn2+ interferes with Mg2+ in the nucleus, and vice versa, Mg2+ interferes with Mn2+ in the Golgi. Consequently, cell cycle progression is challenged by aberrant catalytic activities of enzymes involved in replication and protein glycosylation.
Impaired manganese metabolism causes mitotic misregulation.
No sample metadata fields
View SamplesThe RET/PTC3 (RP3) fusion gene is the most frequent mutation found in radiation-induced papillary thyroid cancers (PTC). Several studies suggest that the RET/PTC rearrangement is an initiating event in tumorigenesis. E7 is an oncoprotein derived from the Human Papilllomavirus 16 (HPV16) responsible for most cervical carcinoma in women. We studied here the sequence of events leading to thyroid cancer in Tg-RP3 and Tg-E7 mice expressing the transgene exclusively in the thyroid under the control of thyroglobulin (Tg) promoter. Both transgenic mice develop thyroid hyperplasia followed by solid differentiated carcinoma in older animals. To understand the different steps leading to carcinoma, we analyzed thyroid gene expression in both strains at different ages (2, 6, 10 months) by microarray technology. Important biological processes were differentially regulated in the two tumor types. In E7 thyroids cell cycle was the most upregulated process; observation consistent with the huge size of these tumors. In RP3 thyroids immunity was the most significantly regulated process, as previously observed in microarray data on human PTC. Interestingly, other human PTC characteristics were also observed in RP3 but not in E7 mouse tumors: similar regulation of several human PTC markers, upregulation of many EGF-like growth factors and finally significant regulation of angiogenesis and extracellular matrix remodeling-related genes. In summary we showed that RP3 contrary to E7 mouse tumors share several important genotypic characteristics with human PTC, observation reinforcing the validity of this model to study human thyroid tumorigenesis.
Gene expression in RET/PTC3 and E7 transgenic mouse thyroids: RET/PTC3 but not E7 tumors are partial and transient models of human papillary thyroid cancers.
No sample metadata fields
View SamplesThe seed maturation program occurs only during late phase of embryo development and repression of the maturation genes is pivotal for seedling development. However, mechanisms that repress the expression of this program in vegetative tissues are not well understood. A genetic screen was performed for mutants that express maturation genes in leaves. Here, it is shown that mutations affecting SDG8 (SET DOMAIN GROUP 8), a putative histone methyltransferase, cause ectopic expression of a subset of maturation genes in leaves. Further, to investigate the relationship between SDG8 and the Polycomb Group (PcG) proteins, which are known to repress many developmentally important genes including seed maturation genes, double mutants was made and formation of somatic embryos was observed on mutant seedlings with mutations in both SDG8 and EMF2 (EMBRYONIC FLOWER 2). Interestingly, double mutant of sdg8 and mutations in VRN2 (VERNALIZATION 2), a paralog of EMF2, grow and develop normally to maturity. Analysis of histone methylation status at chromatins of a number of maturation loci revealed synergistic effect of emf2 and sdg8 on the deposition of the active histone mark, trimethylation of lysine 4 on histone 3 (H3K4me3), which is consistent with high expression of these genes (formation of somatic embryos) in emf2 sdg8 double mutants. These observations demonstrate a functional cooperative interplay between SDG8 and an EMF2-containing PcG complex in maintaining vegetative cell identity by repressing seed genes to promote seedling development. The work also indicates the functional specificities of PcG complexes in Arabidopsis.
Synergistic repression of the embryonic programme by SET DOMAIN GROUP 8 and EMBRYONIC FLOWER 2 in Arabidopsis seedlings.
Specimen part
View SamplesWe have previously shown that rheumatoid factors (RF) produced by Fas-deficient autoimmune-prone mice typically bind autologous IgG2a with remarkably low affinity. Nevertheless, B cells representative of this RF population proliferate vigorously in response IgG2a/chromatin immune complexes through a mechanism dependent on the sequential engagement of the BCR and Toll-like receptor 9 (TLR9). To more precisely address the role of both receptors in this response, we analyzed the signaling pathways activated in AM14 B cells stimulated with these complexes. We found that the BCR not only serves to direct the chromatin complex to an internal compartment where it can engage TLR9 but also transmits a suboptimal signal that in combination with the signals emanating from TLR9 leads to NF?B activation and proliferation. Importantly, engagement of both receptors leads to the upregulation of a group of gene products, not induced by the BCR or TLR9 alone, that include IL-2. These data indicate that autoreactive B cells, stimulated by a combination of BCR and TLR9 ligands, acquire functional properties that may contribute to the activation of additional cells involved in the autoimmune disease process.
Functional outcome of B cell activation by chromatin immune complex engagement of the B cell receptor and TLR9.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Integration of transcript expression, copy number and LOH analysis of infiltrating ductal carcinoma of the breast.
Specimen part, Subject
View SamplesIntroduction: A major challenge in the interpretation of genomic profiling data generated from breast cancer samples is the identification of driver genes as distinct from bystander genes which do not impact tumorigenesis. One way to assess the relative importance of alterations in the transcriptome profile is to combine complementary analyses that assess changes in the copy number alterations (CNAs). This integrated analysis permits the identification of genes with altered expression that map within specific chromosomal regions that demonstrate copy number alterations, providing a mechanistic approach to identify the 'driver genes.
Integration of transcript expression, copy number and LOH analysis of infiltrating ductal carcinoma of the breast.
Specimen part, Subject
View SamplesTranscriptome analysis of LDBM cells stimulated with IL-5
IL-5 triggers a cooperative cytokine network that promotes eosinophil precursor maturation.
Specimen part
View SamplesT cell development comprises a stepwise process of commitment from a multipotent precursor. To define molecular mechanisms controlling this progression, we probed five stages spanning the commitment process using deep sequencing RNA-seq and ChIP-seq methods to track genome-wide shifts in transcription, cohorts of active transcription factor genes, histone modifications at diverse classes of cis-regulatory elements, and binding patterns of GATA-3 and PU.1, transcription factors with complementary roles in T-cell development. The results locate potential promoter-distal cis-elements in play and reveal both activation sites and diverse mechanisms of repression that silence genes used in alternative lineages. Histone marking is dynamic and reversible, and while permissive marks anticipate, repressive marks often lag behind changes in transcription. In vivo binding of PU.1 and GATA-3 relative to epigenetic marking reveals distinctive, factor-specific rules for recruitment of these crucial transcription factors to different subsets of their potential sites, dependent on dose and developmental context. Overall design: Genome-wide expression profiles, global distributions of three different histone modifications, and global occupancies of two transcription factors were examined in five developmentally related immature T populations. High throughput sequencing generated on average 9-30 million of mappable reads (single-read) for each ChIP-seq sample, and 10-15 million (single-read) for RNA-seq. Independent biological replicates were analyzed for individual populations. Terminology: FLDN1_RNA-seq_sample1 and FLDN1_RNA-seq_sample2 are independent biological replicates for the same cell type.
Dynamic transformations of genome-wide epigenetic marking and transcriptional control establish T cell identity.
Specimen part, Cell line, Subject
View Samples