After positive selection in the thymus, the newly generated single positive (SP) thymocytes are phenotypically and functionally immature and undergo apoptosis upon antigen stimulation. In the thymic medullary microenvironment, SP cells progressively acquire immunocompetence. Negative selection to remove autoreactive T cells also occur at this stage. We have defined four subsets of CD4 SP, namely, SP1, SP2, SP3, and SP4 that follow a functional maturation program and a sequential emergence during mouse ontogeny.
The molecular signature underlying the thymic migration and maturation of TCRαβ+ CD4+ CD8 thymocytes.
Specimen part
View SamplesWe used microarrays to explore gene expression fold change in breast cancer cells before and after ATP treatment.
Extracellular ATP drives breast cancer cell migration and metastasis via S100A4 production by cancer cells and fibroblasts.
Cell line, Treatment
View SamplesSOX genes encode a family of high-mobility group transcription factors that play critical roles in organogenesis. Virtually all members of SOX family have been found to be deregulated in tumors of various origins. However, little is known about the cellular and molecular behaviours involved in the oncogenic potential of SOX proteins.
The molecular mechanism governing the oncogenic potential of SOX2 in breast cancer.
No sample metadata fields
View SamplesKindlin-2, an integrin-interacting FERM-domain-containing protein, has been known to play critical roles for tumor progression. However, the role of Kindlin-2 in renal cell carcinoma (RCC) progression has not been reported. We aim to investigate the role of Kindlin-2 in the progression of RCC and the underlying mechanisms.
No associated publication
Specimen part, Cell line
View SamplesGene expression along the crypt-villus (C-V) axis was analyzed using cryostat sectioning to isolate fractions representing the crypts (bottom) and villus tops (top). These fractions were used for analyzing gene expression in iron replete Wistar rats (++), iron deficient Wistar rats (low iron), and in iron deficient Wistar rats fed iron for 3 and 6 days (iron-fed). Differences were observed between the crypts and villus tops in the expression of genes associated with Wnt and BNP signaling, cell proliferation and apoptosis, lipid and iron transport and metabolism. Gene expression in villus crypts and tops was also compared between Wistar and Belgrade rats (bb) and Belgrade rats fed iron (iron-fed) particularly as related to iron absorption and metabolism to define the affects of the mutation in DMT1 in the Belgrade rat on the expression of genes related to iron absorption and metabolism and the response to iron feeding.
Hypoxia-inducible factor-2α and iron absorptive gene expression in Belgrade rat intestine.
No sample metadata fields
View SamplesIn proliferating cells, where most Polycomb repressive complex 2 (PRC2) studies have been performed, gene repression is associated with PRC2 trimethylation of H3K27 (H3K27me3). However, it is uncertain whether PCR2 writing of H3K27me3 is mechanistically required for gene silencing. Here we studied PRC2 function in postnatal mouse cardiomyocytes, where the paucity of cell division obviates bulk H3K27me3 rewriting after each cell cycle. EED (Embryonic Ectoderm Development) inactivation in the postnatal heart (Eed CKO ) caused lethal dilated cardiomyopathy. Surprisingly, gene upregulation in Eed CKO was not coupled with loss of H3K27me3. Rather, the activating histone mark H3K27ac increased. EED interacted with histone deacetylases (HDACs) and enhanced their catalytic activity. HDAC overexpression normalized Eed CKO heart function and expression of derepressed genes. Our results uncovered a non-canonical, H3K27me3-independent EED repressive mechanism that is essential for normal heart function. Our results further illustrate that organ dysfunction due to epigenetic dysregulation can be corrected by epigenetic rewiring.
EED orchestration of heart maturation through interaction with HDACs is H3K27me3-independent.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A systematic analysis of the skeletal muscle miRNA transcriptome of chicken varieties with divergent skeletal muscle growth identifies novel miRNAs and differentially expressed miRNAs.
Specimen part
View SamplesThe genetic closeness and divergent muscle growth rates of broilers and layers make them great models for myogenesis study. In order to discover the molecular mechanisms determining the divergent muscle growth rates and muscle fiber sizes in different chicken lines, we systematically identified differentially expressed genes between broilers and layers during muscle development (embyonic day 10, 12, 14 and 18) by microarray hybridization experiment.
A systematic analysis of the skeletal muscle miRNA transcriptome of chicken varieties with divergent skeletal muscle growth identifies novel miRNAs and differentially expressed miRNAs.
Specimen part
View SamplesThe molecular explanation for tamoxifen serving as a breast cancer treatment but displaying partial estrogenic in the uterus is not known. Previously, we reported that differential promoter context and cofactor recruitment contribute to the tissue specificity of tamoxifen. Here, we investigated the genomic basis for the partial oestrogenic activity of tamoxifen in the endometrium. We showed that tamoxifen not only affects the rate of transcription of oestrogen target genes but also targets a unique set of genes. Since oestrogen and tamoxifen are both able to bind to oestrogen receptors (ERs) and because both promote endometrial carcinogenesis, we hypothesized that the molecular effectors for ERs in endometrial carcinogenesis most likely reside in genes that are commonly targeted by oestrogen and tamoxifen. Among those target genes, we identified a paired-box gene PAX2 that is critically involved in cell proliferation and carcinogenesis in the endometrium. Our experiments also demonstrated that PAX2 is activated by oestrogen and tamoxifen in endometrial carcinomas but not in normal endometrium, and this activation is associated with cancer-linked hypomethylation of the PAX2 promoter.
Hypomethylation-linked activation of PAX2 mediates tamoxifen-stimulated endometrial carcinogenesis.
No sample metadata fields
View SamplesThrough H3K27me3 and H3K27ac ChIP-seq and microarray data in wile-tpye (WT) and EED-knockout (CKO) mouse cardiomyocytes, we unexpectedly uncovered a novel mechanism of PRC2-mediated gene repression. EED inactivation in the postnatal heart (EEDCKO) caused progressive, lethal dilated cardiomyopathy, with upregulation of components of the slow-twitch muscle gene program. Surprisingly, upregulation of these genes was not associated with their loss of H3K27me3, but rather with their gain of H3K27 acetylation (H3K27ac), an activating histone mark4,5. Moreover, re-expression of EED in juvenile hearts rescued heart function and normalized H3K27ac, but not H3K27me3.
No associated publication
Specimen part
View Samples