NCoR and SMRT are two paralogous vertebrate proteins that function as corepressors with unliganded nuclear receptors. Although C. elegans has a large number of nuclear receptors, orthologues of the corepressors NCoR and SMRT have not unambiguously been identified in Drosophila or C. elegans. Here, we identify GEI-8 as the closest homologue of NCoR and SMRT in C. elegans and demonstrate that GEI-8 is expressed as at least two isoforms throughout development in multiple tissues, including neurons, muscle and intestinal cells. We demonstrate that a homozygous deletion within the gei-8 coding region, which is predicted to encode a truncated protein lacking the predicted NR domain, results in severe mutant phenotypes with developmental defects, slow movement and growth, arrested gonadogenesis and defects in cholinergic neurotransmission. Whole genome expression analysis by microarrays identified sets of de-regulated genes consistent with both the observed mutant phenotypes and a role of GEI-8 in regulating transcription. Interestingly, the upregulated transcripts included a predicted mitochondrial sulfide:quinine reductase encoded by Y9C9A.16. This locus also contains non-coding, 21-U RNAs of the piRNA. Inhibition of the expression of the region coding for 21-U RNAs leads to irregular gonadogenesis in the homozygous gei-8 mutants, but not in an otherwise wild-type background, suggesting that GEI-8 may function in concert with the 21-U RNAs to regulate gonadogenesis. Our results confirm that GEI-8 is the orthologue of the vertebrate NCoR/SMRT corepressors and demonstrate important roles for this putative transcriptional corepressor in development and neuronal function.
GEI-8, a homologue of vertebrate nuclear receptor corepressor NCoR/SMRT, regulates gonad development and neuronal functions in Caenorhabditis elegans.
No sample metadata fields
View SamplesDynamic interaction between prostate cancer and the bone microenvironment is a major contributor to metastasis of prostate cancer to bone. In this study we utilized an in-vitro co-culture model of PC3 prostate cancer cells and osteoblasts followed by microarray based gene expression profiling to identify previously unrecognized prostate cancer-bone microenvironment interactions. Factors secreted by PC3 cells resulted in the up-regulation of many genes in osteoblasts associated with bone metabolism and cancer metastasis, including Mmp13, Il-6 and Tgfb2, and down-regulation of Wnt inhibitor Sost. To determine whether altered Sost expression in the bone microenvironment has an effect on prostate cancer metastasis, we co-cultured PC3 cells with Sost knockout (SostKO) osteoblasts and wildtype (WT) osteoblasts and identified several genes differentially regulated between PC3-SostKO osteoblast co-cultures and PC3-WT osteoblast co-cultures. Co-culturing PC3 cells with WT osteoblasts up-regulated cancer-associated long noncoding RNA (lncRNA) MALAT1 in PC3 cells. MALAT1 expression was further enhanced when PC3 cells were co-cultured with SostKO osteoblasts and treatment with recombinant Sost down-regulated MALAT1 expression in these cells. Our results suggest that reduced Sost expression in the tumor microenvironment may promote bone metastasis by up-regulating MALAT1 in prostate cancer.
Cancer-Osteoblast Interaction Reduces Sost Expression in Osteoblasts and Up-Regulates lncRNA MALAT1 in Prostate Cancer.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Expression of microRNA and their gene targets are dysregulated in preinvasive breast cancer.
Sex, Age, Specimen part, Disease
View SamplesIntroduction: microRNAs (miRNAs) are short non-coding RNAs that negatively regulate gene expression and may play a causal role in invasive breast cancer. Since many genetic aberrations of invasive disease are detectable in earlier stages, we hypothesized that miRNA expression dysregulation and the predicted changes in gene expression would also be found in early breast neoplasias. Methods: Expression profiling of 365 miRNAs by RT-qPCR was combined with laser-capture microdissection to obtain an epithelial specific miRNA expression signature of normal breast epithelium (n=9) and of paired samples of histologically normal epithelium (HN) and ductal carcinoma in situ (DCIS) (n=16). To determine how miRNAs may control the expression of co-dysregulated mRNAs we also performed gene expression microarray analysis in the same paired HN and DCIS samples and integrated this with miRNA-target prediction. We further validated several target pairs by modulating the expression levels of miRNAs in MCF7 cells and measured the expression of target mRNAs and proteins. Results: Thirty-five miRNAs were aberrantly expressed between RM, HN and DCIS. Twenty-nine miRNAs and 420 mRNAs were aberrantly expressed between HN and DCIS. Combining these two datasets with miRNA-target prediction we identified two established target pairs (miR-195:CCND1 and miR-21:NFIB) and tested several novel miRNA:mRNA target pairs. Over-expression of the putative tumor-suppressor miR-125b, under-expressed in DCIS, repressed the expression of MEMO1, which is required for ErbB2-driven cell motility (also a target of miR-125b); and NRIP1/RIP140, which modulates the transcriptional activity of the estrogen receptor. Knockdown of the putative oncogenic miRNAs miR-182 and miR-183, both highly over-expressed in DCIS, increased the expression of CBX7 (which regulates E-cadherin expression), DOK4, NMT2, and EGR1. Augmentation of CBX7 by knockdown of miR-182 expression, in turn, positively regulated the expression of E-cadherin, a key protein involved in maintaining normal epithelial cell morphology which is commonly lost during neoplastic progression. Conclusions: These data provide the first miRNA expression profile of normal breast epithelium and of pre-invasive breast carcinoma. Further, we demonstrate that altered miRNA expression can modulate gene expression changes that characterize these early cancers. We conclude that miRNA dysregulation likely plays a substantial role in early breast cancer development.
Expression of microRNA and their gene targets are dysregulated in preinvasive breast cancer.
Sex, Age, Specimen part, Disease
View SamplesRNA was obtained from histologically normal bronchial epithelium of never, former, and current smokers undergoing fiberoptic bronchoscopy.
Reversible and permanent effects of tobacco smoke exposure on airway epithelial gene expression.
Age
View SamplesThis study assessed the transcriptomic profiles of lutein granulosa cells (LGCs) from women with and without PCOS using Affymetrix microarray chips to provide novel information about the molecular changes that occur in these cells when they are treated with a D2-ag (Cb2) and to assess the signal transduction pathways regulated by this treatment.
Dysregulated genes and their functional pathways in luteinized granulosa cells from PCOS patients after cabergoline treatment.
Specimen part, Disease
View SamplesWe used heterokaryon cell fusion based reprogramming and identified the cytokine IL6 as a potential regulator of reprogramming to pluripotency. We generated iPS clones using the four reprogramming factors (4F) Oct4, Klf4, Sox2, and c-Myc. In addition, iPS clones were generated using only three factors (3F: Oct4, Klf4, amd Sox2) with the addition of the cytokine IL6 to reprogramming culture conditions. Global RNA-Seq of the 3F + IL6 derived iPS clones was done for comparison with 4F-derived iPS clones, mouse embryonic stem cells and mouse embryonic fibroblasts. Overall design: This study includes 8 samples: 2 independently derived 3F + IL6 iPS clones, 2 independently derived 4F iPS clones, 2 biological replicates of mouse D3-GFP ES cells, and 2 biological replicates of mouse embryonic fibroblasts (MEFs). The latter 6 samples are provided as references for the 3F + IL6 iPS clones. Poly-A RNA was isolated and prepared for sequencing using the Illumina TruSeq RNA kit (v2) to generate 50bp reads. Reads were aligned to mm10.
NKX3-1 is required for induced pluripotent stem cell reprogramming and can replace OCT4 in mouse and human iPSC induction.
Specimen part, Treatment, Subject
View SamplesInjuries to the anterior cruciate ligament (ACL) often result in post-traumatic osteoarthritis (PTOA). PTOA accounts for ~12% of all osteoarthritis (OA) cases, yet the mechanisms contributing to OA after joint injury are not well understood. To better understand the molecular mechanisms behind PTOA development following ACL injury, we profiled ACL injury-induced gene expression changes in knee joints of three mouse strains with varying susceptibility to PTOA: STR/ort (highly susceptible), C57BL/6 (moderately susceptible) and super-healer MRL/MpJ (not susceptible) and identified genes differentially expressed between these strains at 0-day [before injury], 1-day, 1-week, and 2-weeks post-injury. This study highlights many new potential therapeutic targets and OA biomarkers. Overall design: Comparative transcriptomics to understand the molecular changes associated with early stages of PTOA development in STR/ort, C57BL/6 and MRL/MpJ mice and to identify genes that contribute to increased OA susceptibility in STR/ort and resistance to PTOA in MRL/MpJ.
Comparative Transcriptomics Identifies Novel Genes and Pathways Involved in Post-Traumatic Osteoarthritis Development and Progression.
Age, Specimen part, Cell line, Treatment, Subject
View SamplesDensely ionizing radiation is a major component of the space radiation environment and has potentially greater carcinogenic effect compared to sparsely ionizing radiation that is prevalent in the terrestrial environment. It is unknown to what extent the irradiated microenvironment contributes to the differential carcinogenic potential of densely ionizing radiation. To address this gap, 10-week old BALB/c mice were irradiated with 100 cGy sparsely ionizing g-radiation or 10, 30, or 80 cGy of densely ionizing, 350 MeV/amu Si particles and transplanted 3 days later with syngeneic Trp53 null mammary fragments. Tumor appearance was monitored for 600 days. Tumors arising in Si-particle irradiated mice had a shorter median time to appearance, grew faster and were more likely to metastasize. Most tumors arising in sham-irradiated mice were ER-positive, pseudo-glandular and contained both basal keratin 14 and luminal keratin 8/18 cells (designated K14/18), while most tumors arising in irradiated hosts were K8/18 positive (designated K18) and ER negative. Comparison of K18 vs K14/18 tumor expression profiles showed that genes increased in K18 tumors were associated with ERBB2 and KRAS while decreased genes overlapped with those down regulated in metastasis and by loss of E-cadherin. Consistent with this, K18 tumors grew faster than K14/18 tumors and more mice with K18 tumors developed lung metastases compared to mice with K14/18 tumors. However, K18 tumors arising in Si-particle irradiated mice grew even faster and were more metastatic compared to control mice. A K18 Si-irradiated host profile was enriched in genes involved in mammary stem cells, stroma, and Notch signaling. Thus systemic responses to densely ionizing radiation enriches for a ER-negative, K18-positive tumor, whose biology is more aggressive compared to similar tumors arising in non-irradiated hosts.
Densely ionizing radiation acts via the microenvironment to promote aggressive Trp53-null mammary carcinomas.
No sample metadata fields
View SamplesAccording to Dobzhansky-Muller model, hybrid sterility is a consequence of independent evolution of related taxa resulting in incompatible interaction during gametogenesis of their hybrids. We proposed that asynapsis of heterospecific chromosomes in meiotic prophase provides a general and recurrently evolving trigger for the meiotic arrest of interspecific F1 hybrids. We used genome-wide expression profiling to quantify misexpression of Chr X and Chr Y genes.
Mechanistic basis of infertility of mouse intersubspecific hybrids.
Age, Specimen part
View Samples