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Arabidopsis thaliana
24 Downloadable Samples
Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
The first described feedback loop of the Arabidopsis circadian clock is based on reciprocal regulation between TOC1 and CCA1/LHY. CCA1 and LHY are MYB transcription factors that bind directly to the TOC1 promoter to negatively regulate its expression. Conversely, the activity of TOC1 has remained less well characterized. Genetic data supports that TOC1 is necessary for the reactivation of CCA1/LHY, but there is little description of its biochemical function. Here we show that TOC1 occupies specific genomic regions in the CCA1 and LHY promoters. Purified TOC1 binds directly to DNA through its CCT domain, which is similar to known DNA binding domains. Chemical induction and transient overexpression of TOC1 in Arabidopsis seedlings cause repression of CCA1/LHY expression demonstrating that TOC1 can repress direct targets, and mutation or deletion of the CCT domain prevents this repression showing that DNA binding is necessary for TOC1 action. Furthermore, we use the Gal4/UAS system in Arabidopsis to show that TOC1 acts as a general transcriptional repressor, and that repression activity is in the Pseudoreceiver (PR) domain of the protein. To identify the genes regulated by TOC1 on a genomic scale, we couple TOC1 chemical induction with microarray analysis and identify new potential TOC1 targets and output pathways. Together these results define the biochemical action of the core clock protein TOC1 and refine our perspective on how plant clocks function.
Publication Title
Arabidopsis circadian clock protein, TOC1, is a DNA-binding transcription factor.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Histone deacetylases (Hdac) remove acetyl groups from proteins, influencing global and specific gene expression. Hdacs control inflammation, as shown by Hdac inhibitor-dependent protection from DSS-induced murine colitis. While tissue-specific Hdac knockouts show redundant and specific functions, little is known of their intestinal epithelial cell (IEC) role. We have shown previously that dual Hdac1/Hdac2 IEC-specific loss disrupts cell proliferation and determination, with decreased secretory cell numbers and altered barrier function. We thus investigated how compound Hdac1/Hdac2 or Hdac2 IEC-specific deficiency alters the inflammatory response. Floxed Hdac1 and Hdac2 and villin-Cre mice were interbred. Compound Hdac1/Hdac2 IEC-deficient mice showed chronic basal inflammation, with increased basal Disease Activity Index (DAI) and deregulated Reg gene colonic expression. DSS-treated dual Hdac1/Hdac2 IEC-deficient mice displayed increased DAI, histological score, intestinal permeability and inflammatory gene expression. In contrast to double knockouts, Hdac2 IEC-specific loss did not affect IEC determination and growth, nor result in chronic inflammation. However, Hdac2 disruption protected against DSS colitis, as shown by decreased DAI, intestinal permeability and caspase-3 cleavage. Hdac2 IEC-specific deficient mice displayed increased expression of IEC gene subsets, such as colonic antimicrobial Reg3b and Reg3g mRNAs, and decreased expression of immune cell function-related genes. Our data show that Hdac1 and Hdac2 are essential IEC homeostasis regulators. IEC-specific Hdac1 and Hdac2 may act as epigenetic sensors and transmitters of environmental cues and regulate IEC-mediated mucosal homeostatic and inflammatory responses. Different levels of IEC Hdac activity may lead to positive or negative outcomes on intestinal homeostasis during inflammation
Publication Title
The acetylome regulators Hdac1 and Hdac2 differently modulate intestinal epithelial cell dependent homeostatic responses in experimental colitis.
Sample Metadata Fields
Specimen part
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SRP056295- Homo sapiens
- 523 Downloadable Samples
IlluminaHiSeq2000
Description
RNA sequencing of human leukemia Overall design: The goals of this project are to obtain a comprehensive study of mutations and gene expression in human acute myeloid leukemia (AML). Methods: AML cells were thawed. DNA and RNA (polyA) was extracted and sequences were obtained with an illumina HiSeq 2000 sequencer. Results are pending.
Publication Title
RNA-sequencing analysis of core binding factor AML identifies recurrent ZBTB7A mutations and defines RUNX1-CBFA2T3 fusion signature.
Sample Metadata Fields
No sample metadata fields
View Samples SRP048759- Homo sapiens
- 434 Downloadable Samples
- IlluminaHiSeq2000
Description
RNA sequencing of human leukemia Overall design: The goals of this project are to obtain a comprehensive study of mutations and gene expression in human acute myeloid leukemia (AML). Methods: AML cells were thawed. DNA and RNA (polyA) was extracted and sequences were obtained with an illumina HiSeq 2000 sequencer. Results are pending.
Publication Title
RNA-sequencing analysis of core binding factor AML identifies recurrent ZBTB7A mutations and defines RUNX1-CBFA2T3 fusion signature.
Sample Metadata Fields
No sample metadata fields
View Samples SRP033266- Homo sapiens
- 144 Downloadable Samples
- IlluminaHiSeq2000
Description
RNA sequencing of human leukemia Overall design: The goals of this project are to obtain a comprehensive study of mutations and gene expression in human acute myeloid leukemia (AML). Methods: AML cells were thawed. DNA and RNA (polyA) was extracted and sequences were obtained with an illumina HiSeq 2000 sequencer. Results are pending.
Publication Title
RNA-sequencing analysis of core binding factor AML identifies recurrent ZBTB7A mutations and defines RUNX1-CBFA2T3 fusion signature.
Sample Metadata Fields
No sample metadata fields
View Samples SRP056197- Homo sapiens
- 81 Downloadable Samples
- IlluminaHiSeq2000
Description
RNA sequencing of human leukemia Overall design: The goals of this project are to obtain a comprehensive study of mutations and gene expression in human acute myeloid leukemia (AML). Methods: AML cells were thawed. DNA and RNA (polyA) was extracted and sequences were obtained with an illumina HiSeq 2000 sequencer. Results are pending.
Publication Title
RNA-sequencing analysis of core binding factor AML identifies recurrent ZBTB7A mutations and defines RUNX1-CBFA2T3 fusion signature.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Hepatocyte-nuclear-factor-4 (Hnf4) is a transcription factor that controls epithelial cell polarity and maturation during embryogenesis. Hnf4 conditional deletion during post-natal development results in minor consequences on intestinal epithelium integrity but promotes activation of the Wnt/-catenin pathway. Here we show that Hnf4 does not act as a tumor suppressor gene but is crucial to promote gut tumorigenesis in mice. Polyp multiplicity in ApcMin mice that lacks Hnf4 is suppressed in comparison to littermate ApcMin controls. Analysis of microarray gene expression profiles from mice lacking Hnf4 in the intestinal epithelium identifies its novel function in regulating the expression of reactive oxygen species (ROS) detoxifying genes. This role is supported with the demonstration that HNF4 is functionally involved in the protection against spontaneous and 5-fluorouracil chemotherapy-induced production of intracellular ROS in colorectal cancer cell lines. The analysis of a colorectal cancer patient cohort establishes that HNF4 is significantly up-regulated at both gene transcript and protein levels in tumors relative to adjacent benign epithelial resections. Several genes involved in ROS neutralization are also up-regulated in correlation with HNF4 expression. All together, the findings point to the nuclear receptor HNF4 as a potential therapeutic target to eradicate aberrant epithelial cell resistance to ROS production during intestinal tumorigenesis.
Publication Title
Hepatocyte nuclear factor-4alpha promotes gut neoplasia in mice and protects against the production of reactive oxygen species.
Sample Metadata Fields
Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Background & Aims: HNF4 is an important transcriptional regulator of hepatocyte and pancreatic function. Hnf4 deletion is embryonically lethal with severe defects in visceral endoderm formation, liver maturation and colon development. However, the precise role of this transcription factor in maintaining homeostasis of the adult intestine remains unclear. Herein, we aimed to elucidate the adult intestinal functions of Hnf4. Methods: A conditional intestinal epithelial Hnf4 knockout mouse was generated. Histological abnormality of the colonic mucosa was assessed by immunodetection and Western. Changes in global gene expression and biological network were analyzed. Results: Hnf4 intestine null mice developed normally until reaching young adulthood. Crypt distortion became apparent in the Hnf4 null colon at 3 months of age followed by focal areas of crypt dropout, increased immune cell infiltrates, crypt hyperplasia and early signs of polyposis later in life. A gene profiling analysis identified cell death and cell cycle related to cancer as the most significant sets of genes altered in the Hnf4 colon null mice. Expression levels of the tight junction proteins claudin 4, 8 and 15 were altered early in the colon epithelium of Hnf4 mutants and correlated with increased barrier permeability to a molecular tracer that does not normally penetrate normal mucosa. Conclusion: These observations support a functional role for Hnf4 in protecting the colonic mucosa against the initiation of the changes resembling inflammatory bowel diseases and polyp formation.
Publication Title
Loss of hepatocyte-nuclear-factor-4alpha affects colonic ion transport and causes chronic inflammation resembling inflammatory bowel disease in mice.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
The LIM-only protein FHL2 acts as a transcriptional modulator that positively or negatively regulates multiple signaling pathways. We recently reported that FHL2 cooperates with CBP/p300 in the activation of -catenin/TCF target gene cyclin D1. In this paper, we demonstrate that FHL2 is associated with the cyclin D1 promoter at the TCF/CRE site, providing evidence that cyclin D1 is a direct target of FHL2. We show that deficiency of FHL2 greatly reduces the proliferative capacity of spontaneously immortalized mouse fibroblasts which is associated with decreased expression of cyclin D1 and p16INK4a, and hypophosphorylation of Rb. Reexpression of FHL2 in FHL2-null fibroblasts efficiently restores cyclin D1 levels and cell proliferative capacity, indicating that FHL2 is critical for cyclin D1 activation and cell growth. Moreover, ectopic cyclin D1 expression is sufficient to override growth inhibition of immortalized FHL2-null fibroblasts. Gene expression profiling revealed that FHL2 deficiency triggers a broad change of the cell cycle program that is associated with downregulation of several G1/S and G2/M cyclins, E2F transcription factors and DNA replication machinery, thus correlating with reduced cell proliferation. This change also involves downregulation of the negative cell cycle regulators, particularly INK4 inhibitors, which could counteract the decreased expression of cyclins, allowing cells to grow. Our study illustrates that FHL2 can act on different aspects of the cell cycle program to finely regulate cell proliferation.
Publication Title
The LIM-only protein FHL2 regulates cyclin D1 expression and cell proliferation.
Sample Metadata Fields
No sample metadata fields
View Samples GSE28043- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Pulmonary arterial hypertension (PAH) is thought to be driven by dysfunction of pulmonary vascular microendothelial cells (PMVEC). Most hereditary PAH is associated with BMPR2 mutations.
Publication Title
Physiologic and molecular consequences of endothelial Bmpr2 mutation.
Sample Metadata Fields
Specimen part
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