Project description:We used microarrays to detail the global programme of miRNA expression during neuronal differentiation To study changes in miRNA during neuronal differentiation
Project description:To search for factors regulating neuronal differentiation, we performed a genome-wide loss-of-function CRISPR/Cas9 screen in haploid human ESCs. The regulators were identified by the quantification of depletion of their mutant clones within a pooled loss-of-function library upon neuronal differentiation.
Project description:Gene duplication enables the emergence of new functions by lowering the general evolutionary pressure. Previous studies have highlighted the role of specific paralog genes during cell differentiation, e.g., in chromatin remodeling complexes. It remains unexplored whether similar mechanisms extend to other biological functions and whether the regulation of paralog genes is conserved across species. Here, we analyze the expression of paralogs across human tissues, during development and neuronal differentiation in fish, rodents and humans. While ~80% of paralog genes are co-regulated, a subset of paralogs shows divergent expression profiles, contributing to variability of protein complexes. We identify 78 substitutions of paralog eggNOG pairs that occur during neuronal differentiation and are conserved across species. Among these, we highlight a substitution between the paralogs Sec23a and Sec23b subunits of the COPII complex. Altering the ratio between these two genes via silencing-RNA knockdown was able to influence neuronal differentiation in different ways. We propose that remodeling of the vesicular transport system via paralog substitutions is an evolutionary conserved mechanism enabling neuronal differentiation.
Project description:Gene duplication enables the emergence of new functions by lowering the general evolutionary pressure. Previous studies have highlighted the role of specific paralog genes during cell differentiation, e.g., in chromatin remodeling complexes. It remains unexplored whether similar mechanisms extend to other biological functions and whether the regulation of paralog genes is conserved across species. Here, we analyze the expression of paralogs across human tissues, during development and neuronal differentiation in fish, rodents and humans. While ~80% of paralog genes are co-regulated, a subset of paralogs shows divergent expression profiles, contributing to variability of protein complexes. We identify 78 substitutions of paralog eggNOG pairs that occur during neuronal differentiation and are conserved across species. Among these, we highlight a substitution between the paralogs Sec23a and Sec23b subunits of the COPII complex. Altering the ratio between these two genes via silencing-RNA knockdown was able to influence neuronal differentiation in different ways. We propose that remodeling of the vesicular transport system via paralog substitutions is an evolutionary conserved mechanism enabling neuronal differentiation.
Project description:This SuperSeries is composed of the following subset Series: GSE27114: Expression data from REST knock-out versus REST wild type cells during in vitro neurogenesis GSE27148: A comparative epigenomics approach reveals REST as a mediator of Polycomb reprogramming during neuronal differentiation Refer to individual Series
Project description:Gene duplication enables the emergence of new functions by lowering the general evolutionary pressure. Previous studies have highlighted the role of specific paralog genes during cell differentiation, e.g., in chromatin remodeling complexes. It remains unexplored whether similar mechanisms extend to other biological functions and whether the regulation of paralog genes is conserved across species. Here, we analyze the expression of paralogs across human tissues, during development and neuronal differentiation in fish, rodents and humans. While ~80% of paralog genes are co-regulated, a subset of paralogs shows divergent expression profiles, contributing to variability of protein complexes. We identify 78 substitutions of paralog pairs that occur during neuronal differentiation and are conserved across species. Among these, we highlight a substitution between the paralogs Sec23a and Sec23b subunits of the COPII complex. Altering the ratio between these two genes via RNAi-mediated knockdown is sufficient to influence the differentiation of immature neuron. We propose that remodeling of the vesicular transport system via paralog substitutions is an evolutionary conserved mechanism enabling neuronal differentiation.
Project description:Neuronal differentiation is a multistep process that shapes and re-shapes neurons by progressing through several typical stages, including axon outgrowth, dendritogenesis and synapse formation. To systematically profile protein expression during neuronal differentiation we have used cultured hippocampal neurons at different developmental stages in combination with triplex stable isotope dimethyl labeling technique coupled to high-resolution tandem mass spectrometry (LC-MS/MS). In total >1,500 proteins show more than two-fold expression changes during the different developmental steps, indicating extensive remodeling of the neuron proteome during differentiation. To demonstrate the strength of our resource, we focused on neural cell adhesion molecule 1 (NCAM1) as a regulator for dendritic outgrowth during neuronal development. The transmembrane isoform of NCAM1, NCAM180, is strongly upregulated during dendrite outgrowth, highly enriched in dendritic growth cones and interacts with a large variety of actin binding proteins. Inducing actin polymerization rescues the NCAM1 knockdown phenotype, suggesting that NCAM180 stimulates dendritic arbor development by promoting actin filament growth at the dendritic growth cone. Thus, our quantitative map of neuronal proteome dynamics will serve as a rich resource for further analyses of neurodevelopmental regulated processes.
Project description:Cell differentiation is an essential process of normal development by which a stem cell or progenitor cell becomes a post-mitotic, specialized cell with unique morphology and function. Also, it has long been recognized that differentiation is associated with a marked reduction in DNA damage response at the global level. The molecular basis for the coordination between cell cycle exit, acquirement of specialized structure and function, and attenuation of DNA damage response during differentiation is not well understood. We have conducted a genome-wide analysis of the HOXC9-induced neuronal differentiation program in human neuroblastoma cells. Gene expression profiling reveals that HOXC9-induced differentiation is associated with transcriptional regulation of 2,395 genes, which is characterized by global upregulation of neuronal genes and downregulation of cell cycle and DNA repair genes. Remarkably, genome-wide mapping demonstrates that HOXC9 occupies 40% of these genes, including a large number of genes involved in neuronal differentiation, cell cycle progression and DNA damage response. These findings suggest that HOXC9 directly activates and represses the transcription of distinct sets of genes to coordinate the cellular events characteristic of neuronal differentiation. Two independent preparations of BE(2)-C/Tet-Off/Myc-HOXC9 cells cultured in the absence of doxycycline for 6 days were used for chromatin immunoprecipitation (ChIP) against Myc-tagged HOXC9 and massively parallel sequencing by Illumina Genome Analyzer IIx.