Project description:Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, such as the sequence-specific RNA interference (RNAi) pathway, the sequence-independent interferon response, and RNA editing by adenosine deaminases. To study routing of long dsRNA into different pathways in different tissues, we generated transgenic mice carrying an inverted repeat transcribed by a strong, ubiquitously active polII promoter. Here, we provide the first report of effects caused by ubiquitous long dsRNA expression in the adult mouse. Long dsRNA is poorly processed into siRNAs in somatic cells but readily induces the RNAi effects in the oocyte, suggesting that somatic cells are missing a component of RNAi that facilitates siRNA biogenesis. Expression of dsRNA is not sufficient to activate the interferon pathway and has a minimal effect on the transcriptome in somatic cells. The interferon response in somatic cells could be induced with high doses of dsRNA expression, suggesting that somatic cells can tolerate endogenous dsRNA expression to a large extent. Our data demonstrate that the association between long dsRNA and the interferon pathway in somatic cells cannot be generalized and that cells recognize other features of dsRNA molecules, which increase or reduce the likelihood activation of a particular dsRNA-induced pathway. Brain or kidney tissue (transgenic mice), or HEK293 or HeLa cell lines (human), expressing long dsRNA within the 3'-UTR of the EGFP reporter gene.
Project description:Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference, sequence-independent interferon response and editing by adenosine deaminases. To assess the potential of expressed dsRNA to induce interferon stimulated genes in somatic cells, we performed microarray analysis of HEK293 and HeLa cells transfected with a MosIR plasmid expressing an mRNA with a long inverted repeat structure in its 3’UTR (MosIR) or with a parental MosIR plasmid (without inverted repeat) as a control. Clustering analysis based on differentially expressed genes suggested that there was no common transcriptome signature in cells expressing dsRNA. Overall, the number of genes with altered expression upon transfection of the MosIR plasmid was rather small and only 19 probe sets, corresponding to 17 genes, were changed more than two-fold in both cell lines. Total RNA from cultured HEK293 or HeLa cells was used in each sample. Two independent biological replicates were analyzed for each condition.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression. Two-condition experiment, Normoxic MSCs vs. Hypoxic MSCs.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference, sequence-independent interferon response and editing by adenosine deaminases. To assess the potential of expressed dsRNA to induce interferon stimulated genes in somatic cells, we performed microarray analysis of HEK293 and HeLa cells transfected with a MosIR plasmid expressing an mRNA with a long inverted repeat structure in its 3’UTR (MosIR) or with a parental MosIR plasmid (without inverted repeat) as a control. Clustering analysis based on differentially expressed genes suggested that there was no common transcriptome signature in cells expressing dsRNA. Overall, the number of genes with altered expression upon transfection of the MosIR plasmid was rather small and only 19 probe sets, corresponding to 17 genes, were changed more than two-fold in both cell lines.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs. Two-condition experiment, KP MSCs vs. 3A6 MSCs.