POU4F1 is associated with t(8;21) acute myeloid leukemia (AML) and contributes directly to its unique transcriptional signature
POU4F1 is associated with t(8;21) acute myeloid leukemia and contributes directly to its unique transcriptional signature.
Specimen part
View SamplesAlpha-synuclein is an abundant protein implicated in synaptic function and plasticity, but the molecular mechanism of its action is not understood. Missense mutations and gene duplication/triplication events result in Parkinson's disease, a neurodegenerative disorder of old age with impaired movement and emotion control. Here, we systematically investigated the striatal as well as the cerebellar transcriptome profile of alpha-synuclein-deficient mice via a genome-wide microarray survey in order to gain hypothesis-free molecular insights into the physiological function of alpha-synuclein. A genotype-dependent, specific and strong downregulation of forkhead box P1 (Foxp1) transcript levels was observed in all brain regions from postnatal age until old age and could be validated by qPCR. In view of the co-localization and heterodimer formation of FOXP1 with FOXP2, a transcription factor with a well established role for vocalization, and the reported regulation of both alpha-synuclein and FOXP2 expression during avian song learning, we performed a detailed assessment of mouse movements and vocalizations in the postnatal period. While there was no difference in isolation-induced behavioral activity in these animals, the alpha-synuclein-deficient mice exhibited an increased production of isolation-induced ultrasonic vocalizations (USVs). This phenotype might also reflect the reduced expression of the anxiety-related GABA-A receptor subunit gamma 2 (Gabrg2) we observed. Taken together, we identified an early behavioral consequence of alpha-synuclein deficiency and accompanying molecular changes, which supports the notion that the neural connectivity of sound or emotion control systems is affected.
Alpha-synuclein deficiency affects brain Foxp1 expression and ultrasonic vocalization.
Age, Specimen part
View SamplesParkinson's disease (PD) is an adult-onset movement disorder of largely unknown etiology. We have previously shown that loss-of-function mutations of the mitochondrial protein kinase PINK1 (PTEN induced putative kinase 1) cause the recessive PARK6 variant of PD. Now we generated a PINK1 deficient mouse and observed several novel phenotypes: A progressive reduction of weight and of locomotor activity selectively for spontaneous movements occurred at old age. As in PD, abnormal dopamine levels in the aged nigrostriatal projection accompanied the reduced movements. Possibly in line with the PARK6 syndrome but in contrast to sporadic PD, a reduced lifespan, dysfunction of brainstem and sympathetic nerves, visible aggregates of -synuclein within Lewy bodies or nigrostriatal neurodegeneration were not present in aged PINK1-deficient mice. However, we demonstrate PINK1 mutant mice to exhibit a progressive reduction in mitochondrial preprotein import correlating with defects of core mitochondrial functions like ATP-generation and respiration. In contrast to the strong effect of PINK1 on mitochondrial dynamics in Drosophila melanogaster and in spite of reduced expression of fission factor Mtp18, we show reduced fission and increased aggregation of mitochondria only under stress in PINK1-deficient mouse neurons. Thus, aging Pink1/ mice show increasing mitochondrial dysfunction resulting in impaired neural activity similar to PD, in absence of overt neuronal death. Transcriptome microarray data of Pink1-/- mouse brains in absence of a stressor, even at old age, show remarkably sparse dysregulations. See Gispert-S et al 2009 PLOS ONE.
Potentiation of neurotoxicity in double-mutant mice with Pink1 ablation and A53T-SNCA overexpression.
Age, Specimen part
View SamplesSpinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disorder, which is caused by an unstable CAG-repeat expansion in the SCA2 gene, that encodes a polyglutamine tract (polyQ-tract) expansion in ataxin-2 protein (ATXN2). The RNA-binding protein ATXN2 interacts with the poly(A)-binding protein PABPC1, localizing to ribosomes at the rough endoplasmic reticulum or to polysomes. Under cell stress ATXN2 and PABPC1 show redistribution to stress granules where mRNAs are kept away from translation and from degradation. It is unknown whether ATXN2 associates preferentially with specific mRNAs or how it modulates their processing. Here, we investigated Atxn2 knock-out (Atxn2-/-) mouse liver, cerebellum and midbrain regarding their RNA profile, employing oligonucleotide microarrays for screening and RNA deep sequencing for validation. Modest ~1.4-fold upregulations were observed for the level of many mRNAs encoding ribosomal proteins and other translation pathway factors. Quantitative reverse transcriptase PCR and immunoblots in liver tissue confirmed these effects and demonstrated an inverse correlation also with PABPC1 mRNA and protein. ATXN2 deficiency also enhanced phosphorylation of the ribosomal protein S6, while impairing the global protein synthesis rate, suggesting a block between the enhanced translation drive and the impaired execution. Furthermore, ATXN2 overexpression and deficiency retarded cell cycle progression. ATXN2 mRNA levels showed a delayed phasic twofold increase under amino acid and serum starvation, similar to ATXN3, but different from motor neuron disease genes MAPT and SQSTM1. ATXN2 mRNA levels depended particularly on mTOR signalling. Altogether the data implicate ATXN2 in the adaptation of mRNA translation and cell growth to nutrient availability and stress.
Genetic ablation of ataxin-2 increases several global translation factors in their transcript abundance but decreases translation rate.
Age, Specimen part
View SamplesWe tested the hypothesis that a set of differentially expressed genes could be used to predict cardiovascular phenotype in mice after prolonged catecholamine stress.
Gene expression profiling: classification of mice with left ventricle systolic dysfunction using microarray analysis.
No sample metadata fields
View SamplesThe goal of this study was to identify the molecular characteristics and putative markers distinguishing IL-10eGFP+CD138hi and IL-10eGFP-CD138hi plasmocytes. To this end, IL-10eGFP B-green mice were challenged intravenously with Salmonella typhimurium (strain SL7207, 10e7 CFU), and IL-10eGFP+CD138hi as well as IL-10eGFP-CD138hi plasmocytes were isolated from the spleen on the next day. For this, single cell suspensions were prepared, cells were treated with Fc block (10 g/ml, anti-CD16/CD32, clone 2.4G2), and then stained with an antibody against CD138 conjugated to PE (1/400; from BD Pharmingen) followed by incubation with anti-PE microbeads (Miltenyi Biotech). CD138+ cells were then enriched on Automacs (Miltenyi Biotech) using the program possel_d2. Cells were then stained with anti-CD19-PerCP, anti-CD138-PE, and antibodies against CD11b, CD11c, and TCR conjugated to APC as a dump channel to exclude possible contaminants. DAPI was added to exclude dead cells. Live IL-10eGFP+CD138hi and IL-10eGFP-CD138hi cells were subsequently isolated on a cell sorter. The purity of the samples was always above 98%. This led to the identification of LAG-3 as a cell surface receptor specifically expressed on IL-10eGFP+CD138hi cells but not on IL-10eGFP-CD138hi cells.
LAG-3 Inhibitory Receptor Expression Identifies Immunosuppressive Natural Regulatory Plasma Cells.
Sex, Specimen part
View SamplesCD8 T cells play a crucial role in immunity to infection and cancer. They are maintained in constant numbers, but upon stimulation with antigen undergo a developmental program characterized by distinct phases encompassing the expansion and then contraction of antigen-specific populations, followed by the persistence of long-lived memory cells. Although this predictable pattern of a CD8 T cell response is well established, the underlying cellular mechanisms regulating the transition to memory remain undefined. Here we show that TRAF6, an adapter protein in the TNF-receptor (TNFR) and IL-1R/TLR superfamily, regulates CD8 T cell memory development following infection by modulating fatty acid metabolism. We show that mice with a T cell-specific deletion of TRAF6 mount robust primary CD8 T cell effector responses, but have a profound defect in their ability to generate memory. This defect is CD8 T cell intrinsic and is characterized by the disappearance of antigen-specific cells in the weeks following primary immunization. Microarray analyses revealed that TRAF6-deficient CD8 T cells from early timepoints following immunization exhibit altered expression of genes that regulate fatty acid metabolism. Consistent with this, activated CD8 T cells lacking TRAF6 are unable to upregulate mitochondrial -oxidation in response to growth factor withdrawal in vitro. Treatment with drugs that induce fatty acid oxidation enabled CD8 T cell memory generation in the absence of TRAF6. Remarkably, these treatments also increased CD8 T cell memory in wild type mice, and consequently were able to significantly improve the efficacy of an experimental anti-cancer vaccine.
Enhancing CD8 T-cell memory by modulating fatty acid metabolism.
Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
MEK inhibition induces MYOG and remodels super-enhancers in RAS-driven rhabdomyosarcoma.
Treatment, Time
View SamplesC2C12 mouse myoblasts expressing RAS mutants identified in human tumors fail to differentiate in low serum media.
MEK inhibition induces MYOG and remodels super-enhancers in RAS-driven rhabdomyosarcoma.
No sample metadata fields
View SamplesThe human cytomegalovirus (HCMV) encodes the chemokine receptor US28 that exhibits constitutive activity. NIH-3T3 cells stably transfected with US28 present a pro-angiogenic and transformed phenotype both in vitro and in vivo.
The human cytomegalovirus-encoded chemokine receptor US28 promotes angiogenesis and tumor formation via cyclooxygenase-2.
No sample metadata fields
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