The hemibiotrophic fungal pathogen Colletotrichum graminicola is the causal agent of anthracnose disease on maize stalks and leaves. After the formation of appressoria the host cell wall is penetrated by the conversion of appressorial turgor pressure into forceful ejection of a penetration peg. Subsequently, C. graminicola establishes biotrophic hyphae in the penetrated epidermis cell at around 36 hours post inoculation (hpi) until a switch of hyphal morphology and lifestyle takes place during the colonization of neighboring host cells at around 72 hpi. During the ensuing necrotrophic growth, dark necrotic lesions are formed that are visible as anthracnose symptoms. We used microarrays to detail the global programme of gene expression during the infection process of Colletotrichum graminicola in its host plant to get insight into the defense response of this compatible interaction and into the metabolic reprogramming needed to supply the fungus with nutrients.
Common Motifs in the Response of Cereal Primary Metabolism to Fungal Pathogens are not Based on Similar Transcriptional Reprogramming.
Time
View SamplesTo uncover molecular mechanisms specifically involved in the pathogenesis of colitis-associated colon cancer (CAC), we studied tumorigenesis in experimental models of CAC and sporadic CRC that mimic characteristics of human CRC. Using comparative whole genome expression profiling, we observed differential expression of epiregulin (Ereg) in mouse models of colitis-associated, but not sporadic colorectal cancer. Similarly, highly significant upregulation of Ereg expression was found in cohorts of patients with colitis-associated cancer in inflammatory bowel disease but not in sporadic colorectal cancer. Furthermore, tumor-associated fibroblasts were identified as major source of Ereg in colitis-associated neoplasias. Functional studies showed that Ereg-deficient mice, although more prone to colitis, are strongly protected from colitis-associated tumors, and data from serial endoscopic studies revealed that Ereg promotes growth rather than initiation of tumors.
Tumor fibroblast-derived epiregulin promotes growth of colitis-associated neoplasms through ERK.
Sex, Specimen part
View SamplesSTAT3 is a pleiotropic transcription factor with important functions in cytokine signalling in a variety of tissues. However, the role of STAT3 in the intestinal epithelium is not well understood. Here we demonstrate that development of colonic inflammation is associated with the induction of STAT3 activity in intestinal epithelial cells (IEC). Studies in genetically engineered mice showed that epithelial STAT3 activation in DSS colitis is dependent on IL-22 rather than IL-6. IL-22 was secreted by colonic CD11c+ cells in response to Toll-like receptor stimulation. Conditional knockout mice with an IEC specific deletion of STAT3 activity were highly susceptible to experimental colitis, indicating that epithelial STAT3 regulates gut homeostasis. STAT3IEC-KO mice, upon induction of colitis, showed a striking defect of epithelial restitution. Gene chip analysis indicated that STAT3 regulates the cellular stress response, apoptosis and pathways associated with wound healing in IEC. Consistently, both IL-22 and epithelial STAT3 were found to be important in wound-healing experiments in vivo. In summary, our data suggest that intestinal epithelial STAT3 activation regulates immune homeostasis in the gut by promoting IL-22-dependent mucosal wound healing.
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Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
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Age, Specimen part
View SamplesExpression changes in testes of 15-20 week old mice after knockout of Phf13 were analyzed using Affymetrix mouse genome 430 2.0 expression microarrays. Transcripts on the X- and Y-chromosome were significantly upregulated.
No associated publication
Specimen part
View SamplesExpression changes in testes of 5 week old mice after knockout of Phf13 were analyzed using Affymetrix mouse genome 430 2.0 expression microarrays. Transcripts on the X- and Y-chromosome were significantly upregulated.
No associated publication
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
The transcription factor prospero homeobox protein 1 is a direct target of SoxC proteins during developmental vertebrate neurogenesis.
Specimen part
View SamplesThe HMG-domain containing SoxC transcription factors Sox4 and Sox11 are expressed in the vertebrate central nervous system in neuronal precursors and neuroblasts. They are required during early stages of neurogenesis.
The transcription factor prospero homeobox protein 1 is a direct target of SoxC proteins during developmental vertebrate neurogenesis.
Specimen part
View SamplesThe HMG-domain containing SoxC transcription factors Sox4 and Sox11 are expressed in the vertebrate central nervous system in neuronal precursors and neuroblasts. They are required during early stages of neurogenesis.
The transcription factor prospero homeobox protein 1 is a direct target of SoxC proteins during developmental vertebrate neurogenesis.
Specimen part
View SamplesNotch3 expression was analyzed in 20 patients suffering from colorectal carcinoma (CRC) and their corresponding colonic normal (NC) tissue.
Notch3 signalling promotes tumour growth in colorectal cancer
Specimen part, Disease, Disease stage
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