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: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: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:We have sequenced miRNA libraries from human embryonic, neural and foetal mesenchymal stem cells. We report that the majority of miRNA genes encode mature isomers that vary in size by one or more bases at the 3’ and/or 5’ end of the miRNA. Northern blotting for individual miRNAs showed that the proportions of isomiRs expressed by a single miRNA gene often differ between cell and tissue types. IsomiRs were readily co-immunoprecipitated with Argonaute proteins in vivo and were active in luciferase assays, indicating that they are functional. Bioinformatics analysis predicts substantial differences in targeting between miRNAs with minor 5’ differences and in support of this we report that a 5’ isomiR-9-1 gained the ability to inhibit the expression of DNMT3B and NCAM2 but lost the ability to inhibit CDH1 in vitro. This result was confirmed by the use of isomiR-specific sponges. Our analysis of the miRGator database indicates that a small percentage of human miRNA genes express isomiRs as the dominant transcript in certain cell types and analysis of miRBase shows that 5’ isomiRs have replaced canonical miRNAs many times during evolution. This strongly indicates that isomiRs are of functional importance and have contributed to the evolution of miRNA genes
Project description:Our results suggest that 48h of immobilization increases expression of mRNA for components of the UPP and MT function while decreasing mRNA and protein for components involved in ECM integrity. We hypothesized that 48h of immobilization would increase gene expression and respective protein products for components of the ubiquitin proteasome pathway (UPP). Keywords: stimulus or stress design
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. One-condition experment, gene expression of 3A6
Project description:Advancements in animal models and cell culture techniques have been invaluable in the elucidation of molecular events and mechanisms regulating muscle atrophy. However, few studies have examined muscle atrophy in humans using modern experimental techniques. The purpose of this study was to examine and validate changes in global gene transcription during immobilization-induced muscle atrophy in humans. Healthy men and women (N=24) were subjected to two weeks of unilateral limb immobilization, with muscle biopsies obtained before, and after 48 hours (48H) and 14 days (14D) of immobilization. Both muscle cross sectional area (~ 5 %) and strength (10-20 %) were significantly reduced in men and women after 14D of immobilization. Micro-array analysis of total RNA extracted from biopsy samples uncovered 575 and 3,128 probes representing multiple genes, which were significantly altered at 48H and 14D, respectively. As a group, genes involved in mitochondrial bioenergetics and carbohydrate metabolism were predominant features at both 48H and 14D, with genes involved in protein synthesis and degradation significantly down-regulated and up-regulated, respectively, at 14D of muscle atrophy. There was also a significant decrease in the protein content of mitochondrial cytochrome c oxidase, and the enzyme activity of cytochrome c oxidase and citrate synthase after 14D of immobilization. Furthermore, protein ubiquitination and oxidative damage were significantly increased by 48H and 14D of immobilization, respectively. These results suggest that transcriptional and post-transcriptional suppression of mitochondrial processes is sustained throughout 14D of immobilization, while protein ubiquitination plays an early but transient role in the progression of immobilization-induced muscle atrophy in humans.