Project description:Whereas cloning mammals by direct somatic cell nuclear transfer has been successful using a wide range of donor cell types, neurons from adult brain remain M-bM-^@M-^\unclonableM-bM-^@M-^] for unknown reasons. Here we examined whether neurons from adult mice could be cloned, using a combination of two epigenetic approaches. First, we used a specific antibody to discover cell types with reduced amounts of a repressive histone mark - dimethylated histone H3 lysine 9 (H3K9me2) - and identified CA1 pyramidal cells in the hippocampus and Purkinje cells in the cerebellum as candidates. Second, reconstructed embryos were treated with trichostatin A (TSA), a potent histone deacetylase inhibitor. Using CA1 cells, cloned offspring were obtained at high rates, reaching 10.2% and 4.6% (per embryos transferred) for male and female donors, respectively. Cerebellar Purkinje cell nuclei were too large to maintain their genetic integrity during nuclear transfer, leading to developmental arrest of embryos. However, gene expression analysis using cloned blastocysts corroborated a high rate of genomic reprogrammability of CA1 pyramidal and Purkinje cells. Neurons from the hippocampal dentate gyrus and cerebral cortex, which had higher amounts of H3K9me2, could also be used for producing cloned offspring, but the efficiencies were low. A more thorough analysis revealed that TSA treatment was essential for cloning adult neuronal cells. This study demonstrated for the first time that adult neurons could be cloned by nuclear transfer. Furthermore, our data imply that reduced amounts of H3K9me2 and increased histone acetylation appear to act synergistically to improve the development of cloned embryos. Comparative gene expression analyses using blastocysts of cloned embryos were performed by microarray. Cloned embryos were produced with three different types of donor cells (neonatal Sertoli cells, CA1 pyramidal cells and Purkinje cells) and all cloned embryos were treated with Trichostatin A (TSA). Each embryos were cultured for 96 h and blastocysts derived from each donor cell types were subjected to gene expression microarray. For comparison of gene expression, the data sets of control sex- and genotype-matched embryos produced by in vitro fertilization and SCNT-derived blastocysts from cumulus cells treated with TSA from our previous paper (Inoue K. et al. Science 2010) were also used.
Project description:<p>RNA sequencing was performed on human DRGs and relative gene abundances were calculated.</p> <p>Various analyses were performed:</p> <p> <ol> <li>Human DRG gene expression profiles were contrasted with a panel of gene expression profiles of relevant tissues in human and mouse ( integrating, among other sources, datasets from ENCODE and GTex ) in order to identify.</li> <ol type="a"> <li>DRG-enriched gene expression, co-expression modules of DRG-expressed genes, and key transcriptional regulators in humans.</li> <li>Contrasting the human and mouse DRG transcriptomes to identify DRG-enriched gene expression patterns that were conserved between human and mouse, identifying putative cell types of expression of these genes, and potential known drugs that might target the corresponding gene products.</li> <li>Characterization of non-coding RNA profile of human and mouse DRGs.</li> <li>Characterization of DRG-enriched alternative splicing and alternative transcription start site usage based transcript variants in humans and mouse, and the overlap between these two species.</li> <li>Contrasting of human DRG and GTex human tibial nerve samples to identify putative axonally transported mRNAs in sensory neurons.</li> </ol> <li>Human DRG transcriptomes from donors suffering from neuropathic and/or chronic pain were contrasted with controls to identify.</li> <ol type="a"> <li>Differentially expressed genes, pathways and regulators path play a potential role in neuronal plasticity, electrophysiological activity, immune signaling and response.</li> <li>Predictive models (Random Forests) were built to jointly predict the sex and pain state of samples based on information contained solely in autosomal gene expression profile.</li> <li>Gene co-expression modules were identified and gene set enrichment analysis performed.to identify sample - pathway associations, and to broadly characterize plasticity in human DRG cell types.</li> </ol> </ol> </p>