Chromodomains are found in many regulators of chromatin structure. Most of them recognize methylated histones. Here, we investigate the role of the Corto chromodomain. This Drosophila melanogaster Enhancer of Polycomb and Trithorax is involved in both silencing and activation of gene expression. Overexpression of Corto chromodomain (CortoCD) in transgenic flies show that this domain is critical for Corto function and behaves as a chromatin-targeting module. Mass spectrometry analysis of peptides pulled down by CortoCD from nuclear extracts reveals that they correspond to nuclear ribosomal proteins (RPs). Notably, CortoCD binds with high affinity RPL12 tri-methylated on lysine 3 (RPL12K3me3) as demonstrated by real-time interaction analyses. Co-localization of Corto and RPL12 with active epigenetic marks on polytene chromosomes suggests that they are involved in fine-tuning transcription of genes located in open chromatin. Hence, pseudo-ribosomal complexes composed of various RPs might participate in regulation of gene expression in connection with chromatin regulators. RNA-seq analysis of wing imaginal discs overexpressing either Corto or RPL12 show that most deregulated genes are shared by both factors. Interestingly, these common targets are enriched in RP genes suggesting that Corto and RPL12 are involved in dynamic coordination of ribosome biogenesis. Overall design: To address the role of Corto and RPL12 in regulation of transcription, we deep-sequenced transcripts of wing imaginal discs from third instar larvae over-expressing either FH-cortoCD or RpL12-Myc under control of the wing-specific scalloped::Gal4 driver (sd::Gal4>UAS::FH-cortoCD or sd::Gal4>UAS::RpL12-Myc). Total RNA from FH-cortoCD or RpL12-Myc, the sd::Gal4/+ control or a w1118 reference line were isolated from pools of wing imaginal discs and subjected to RNA-seq on an Illumina high throughput sequencer.
New partners in regulation of gene expression: the enhancer of Trithorax and Polycomb Corto interacts with methylated ribosomal protein l12 via its chromodomain.
Specimen part, Subject
View SamplesSocial experience influences multiple behaviors of many animal species, including aggression. Social isolation often increases aggressiveness. To investigater the molecular basis of social influences on aggressiveness, we performed comparative gene expression profiling on heads from 6-day-old, single-housed, more aggressive and group-housed, less aggressive male flies.
A common genetic target for environmental and heritable influences on aggressiveness in Drosophila.
No sample metadata fields
View SamplesThe transcriptome of zebrafish embryos treated with a Nodal signaling inhibitor at sphere stage, which causes neural tube defects, is compared to those treated at 30% epiboly, which does not. Overall design: Transcriptomic analysis of differential gene expression of key developmental pathways under differing inhibitory treatments.
Identification of transcripts potentially involved in neural tube closure using RNA sequencing.
No sample metadata fields
View SamplesThe goal of this study is to determine the effects of adipose-specific Glut4 overexpression or knockout on changes in adipose tissue global gene expression
A novel ChREBP isoform in adipose tissue regulates systemic glucose metabolism.
Sex, Age
View SamplesProtein synthesis belongs to the most energy consuming processes in the cell. Lowering oxygen tension below normal (hypoxia) causes a rapid inhibition of global mRNA translation due to the decreased availability of energy. Interestingly, subsets of mRNAs pursue active translation under such circumstances. In human fibrosarcoma cells (HT1080) exposed to prolonged hypoxia (36 h, 1% oxygen) we observed that transcripts are either increasingly or decreasingly associated with ribosomes localized at the endoplasmic reticulum (ER). In a global setting it turned out that only 31% of transcripts showing elevated total-RNA levels were also increasingly present at the ER in hypoxia. These genes, regulated by its expression as well as its ER-localization, belong to the gene ontologys hypoxia response, glycolysis and HIF-1 transcription factor network supporting the view of active mRNA translation at the ER during hypoxia. Interestingly, a large group of RNAs was found to be unchanged at the expression level, but translocate to the ER in hypoxia. Among these are transcripts encoding translation factors and >180 ncRNAs. In summary, we provide evidence that protein synthesis is favoured at the ER and, thus, partitioning of the transcriptome between cytoplasmic and ER associated ribosomes mediates adaptation of gene expression in hypoxia.
Hypoxia-induced gene expression results from selective mRNA partitioning to the endoplasmic reticulum.
Specimen part, Cell line
View SamplesWe used microarray analysis to identify differences in gene expression levels, in liver and in quadriceps skeletal muscle, between 18h (overnight) fasted WT control and Kruppel-like factor 15 (KLF15)-null mice.
Regulation of gluconeogenesis by Krüppel-like factor 15.
No sample metadata fields
View SamplesApproximately 30% of women diagnosed with ERa breast cancer relapse with metastatic disease following adjuvant treatment with endocrine therapies. The connection between acquisition of drug resistance and invasive potential is poorly understood. In this study, we demonstrate that the type II keratin topological associating domain (TAD) undergoes epigenetic reprogramming in cells that develop resistance to aromatase inhibitors (AI), leading to keratin 80 (KRT80) upregulation. In agreement, an increased number of KRT80-positive cells are observed at relapse in vivo while KRT80 expression associates with poor outcome using several clinical endpoints. KRT80 expression is driven by de novo enhancer activation by sterol regulatory element-binding protein 1 (SREBP1). KRT80 upregulation directly promotes cytoskeletal rearrangements at the leading edge, increased focal adhesion maturation and cellular stiffening, which collectively promote cancer cell invasion. Shear-wave elasticity imaging of tumors from prospectively recruited patients shows that KRT80 levels correlate with stiffer tumors in vivo. Collectively, our data uncover an unpredicted and potentially targetable direct link between epigenetic and cytoskeletal reprogramming promoting cell invasion in response to chronic AI treatment. Overall design: Total RNA profiling of MCF7 breast adenocarcinoma cell line and MCF7 overexpressing KRT80. Experiments were carried out in four replicates in both cell lines.
SREBP1 drives Keratin-80-dependent cytoskeletal changes and invasive behavior in endocrine-resistant ERα breast cancer.
No sample metadata fields
View SamplesWe used microarray analysis to investigate if keratinocytes excert an immuno-inflammatory response towards streptococcal M1 protein.
Vigilant keratinocytes trigger pathogen-associated molecular pattern signaling in response to streptococcal M1 protein.
Specimen part, Cell line
View SamplesDUSP1 is involved in different cellular pathways including cancer cell proliferation, angiogenesis, invasion and resistance to chemotherapy. To understand more about the cellular responses regulated by DUSP1 in NSCLC cells, we interfered DUSP1 expression in the NSCLC cell line H460 and studied the changes in gene expression differentially regulated by this phosphatase.
DUSP1/MKP1 promotes angiogenesis, invasion and metastasis in non-small-cell lung cancer.
Specimen part, Cell line
View SamplesThe Wnt gene family is an evolutionarily conserved group of proteins that regulate cell growth, differentiation, and stem cell self-renewal. Aberrant Wnt signaling in human breast tumors has been proposed to be an attractive drug target, especially in the basal-like subtype where canonical Wnt signaling is both enriched and predictive of poor clinical outcomes. The development of effective Wnt based therapeutics, however, has been slowed in part by a limited understanding of the context dependent nature with which these aberrations influence breast tumorigenesis. We recently reported that MMTV-Wnt1 mice, which are an established model for studying Wnt signaling in breast tumors, develop two subtypes of tumors by gene expression classification: Wnt1-EarlyEx and Wnt1-LateEx. Here, we extend this initial observation and show that Wnt1-EarlyEx tumors had high expression of canonical Wnt, non-canonical Wnt, and EGFR signaling pathway signatures. Therapeutically, Wnt1-EarlyEx tumors had a dynamic reduction in tumor volume when treated with an EGFR inhibitor. Wnt1-EarlyEx tumors also had primarily Cd49fpos/Epcamneg FACS profiles, but were unable to be serially transplanted into wild-type FVB female mice. Wnt1-LateEx tumors, conversely, had a bloody gross pathology, which was highlighted by the presence of 'blood lakes' by H&E staining. These tumors had primarily Cd49fpos/Epcampos FACS profiles, but also contained a secondary Cd49fpos/Epcamneg subpopulation. Wnt1-LateEx tumors were enriched for activating Hras1 mutations and were capable of reproducing tumors when serially transplanted into wild-type FVB female mice. This study definitely shows that the MMTV-Wnt1 mouse model produces two phenotypically distinct subtypes of mammary tumors. Importantly, these subtypes differ in their therapeutic response to an EGFR inhibitor, suggesting that a subset of human tumors with aberrant Wnt signaling may also respond to erlotinib. Overall design: Agilent gene expression microarrays were performed comparing RNA from FVB/n MMTV-Wnt1 mammary tumors to a common mouse reference sample. Agilent CGH microarrays were performed comparing DNA from FVB/n MMTV-Wnt1 mammary tumors to DNA from FVB wild-type mice. RNAseq libraries were prepared from FVB/n MMTV-Wnt1 mammary tumors using a TruSeq RNA kit before being submitted to the Lineberger Comprehensive Cancer Center Genomics Core to be run on the Illumina HiSeq 2000.
The MMTV-Wnt1 murine model produces two phenotypically distinct subtypes of mammary tumors with unique therapeutic responses to an EGFR inhibitor.
Specimen part, Subject
View Samples