Stem and progenitor cells maintain the tissue they reside in for life by regulating the balance between proliferation and differentiation. How this is done is not well understood. Here, we report that DDX6 is necessary for maintaining human epidermal progenitor cell self-renewal.
DDX6 Orchestrates Mammalian Progenitor Function through the mRNA Degradation and Translation Pathways.
Specimen part
View SamplesWe used microarrays to investigate gene expression changes in the pancreas of RasGrf1 KO mice. These animals have a reduction in the number and size of the pancreatic islets which lead to lower levels of insulin and glucagon in their blood.
Transcriptional profiling reveals functional links between RasGrf1 and Pttg1 in pancreatic beta cells.
Specimen part
View SamplesHER2 is a tyrosine kinase receptor causally involved in cancer. A subgroup of breast cancer patients with particularly poor clinical outcome expresses a heterogeneous collection of HER2 carboxy-terminal fragments (CTFs). However, since the CTFs lack the extracellular domain that drives dimerization and subsequent activation of full-length HER2, they are in principle expected to be inactive. Here we present evidence that at low expression levels one of these fragments, 611-CTF, activated multiple signaling pathways because of its unanticipated ability to constitutively homodimerize. A transcriptomic analysis revealed that 611-CTF specifically controlled the expression of genes that we found correlated with poor prognosis in breast cancer. Among the 611-CTF-regulated genes were several that previously have been linked to metastasis, including MET, EPHA2, MMP1, IL11, ANGPTL4 and different Integrins. Transgenic mice overexpressing HER2 in the mammary gland develop tumors only after acquisition of activating mutations in the transgene. In contrast, we show that expression of 611-CTF led to development of aggressive and invasive mammary tumors without the need for mutations. These results demonstrate that 611-CTF is a potent oncogene capable of promoting mammary tumor progression and metastasis.
A naturally occurring HER2 carboxy-terminal fragment promotes mammary tumor growth and metastasis.
Cell line, Time
View SamplesCurrent methods to analyze gene expression measure steady-state levels of mRNA. In order to specifically analyze mRNA transcription, a technique has been developed that can be applied in-vivo. The technique is referred with the acronym NIAC-NTR (Non Invasive Application and Capture of Newly Transcribed RNA). This method makes use of the cellular pyrimidine salvage pathway and is based on affinity-chromatographic isolation of thiolated mRNA. When combined with data on mRNA steady-state levels, this method is able to assess the relative contributions of mRNA synthesis and degradation/stabilization. It overcomes limitations associated with currently available methods such as mechanistic intervention that disrupts cellular physiology, or the inability to apply the techniques in-vivo. The method has been applied to a model of serum response of cultured primary mouse embryonic fibroblasts.
Microarray analysis of newly synthesized RNA in cells and animals.
No sample metadata fields
View SamplesCurrent methods to analyze gene expression measure steady-state levels of mRNA. In order to specifically analyze mRNA transcription, a technique has been developed that can be applied in-vivo in intact cells and animals. The technique is referred with the acronym NIAC-NTR (Non Invasive Application and Capture of Newly Transcribed RNA). This method makes use of the cellular pyrimidine salvage pathway and is based on affinity-chromatographic isolation of thiolated mRNA. When combined with data on mRNA steady-state levels, this method is able to assess the relative contributions of mRNA synthesis and degradation/stabilization. It overcomes limitations associated with currently available methods such as mechanistic intervention that disrupts cellular physiology, or the inability to apply the techniques in-vivo. The method was applied to study renal ischemia reperfusion injury, demonstrating its applicability for whole organs in-vivo.
Microarray analysis of newly synthesized RNA in cells and animals.
Age
View SamplesIn Arabidposis thaliana, the msh1 recA3 double mutant shows an extensive mitochondrial genome rearrangement and displays pronounced thermotolerance.
Extensive rearrangement of the Arabidopsis mitochondrial genome elicits cellular conditions for thermotolerance.
Specimen part
View SamplesSingle mutant msh1
Extensive rearrangement of the Arabidopsis mitochondrial genome elicits cellular conditions for thermotolerance.
No sample metadata fields
View SamplesDouble mutant msh1 and recA3
Extensive rearrangement of the Arabidopsis mitochondrial genome elicits cellular conditions for thermotolerance.
No sample metadata fields
View Sampleswe evaluated the mechanism behind NOTCH activation in prostate cancer
Inhibition of Notch pathway arrests PTEN-deficient advanced prostate cancer by triggering p27-driven cellular senescence.
Specimen part
View SamplesThe soybean msh1 RNAi transgenic line show various growth phenotype. We use microarray analysis to characterize gene expression pattern for two of the phenotypes - variegation and stunted growth.
MutS HOMOLOG1 is a nucleoid protein that alters mitochondrial and plastid properties and plant response to high light.
Specimen part
View Samples