Project description:To investigate whether Rbfox3 could alter the expression level of miRNAs during neuronal differentiation of P19 cells, we performed miRNA microarray analysis using the RNAs extracted from untreated (undifferentiated) P19-GFP, RA-treated (neuronally differentiated) P19-GFP, or RA-treated P19-T2 cells.
Project description:To investigate whether Rbfox3 could alter the expression level of miRNAs during neuronal differentiation of P19 cells, we performed miRNA microarray analysis using the RNAs extracted from untreated (undifferentiated) P19-GFP, RA-treated (neuronally differentiated) P19-GFP, or RA-treated P19-T2 cells. Total 9 samples were analyzed. We compared expression levels of P19-GFP (-) vs P19-GFP (+) vs P19-T2 (+) to identify miRNAs which had changes in expression levels with p < 0.01. From this miRNA list, we compared among P19-GFP (-) vs P19-GFP (+) vs P19-T2 (+) to identify the miRNAs which appeared to correlate with Rbfox3 expression.
Project description:The direct conversion of human skin fibroblasts to neurons has a low efficiency and unclear mechanism. Here, we show that the knockdown of PTBP2 (nPTB) significantly enhanced the transdifferentiation induced by ASCL1, MiR124-9/9* and p53 shRNA to generate mostly GABAergic neurons. Longitudinal RNAseq analyses identified the continuous induction of many RNA Splicing Regulators (RSRs). Among these, the knockdown of RBFOX3, which encodes the mature neuronal marker NeuN, significantly abrogated the transdifferentiation. Overexpression of RBFOX3 significantly enhanced the conversion induced by AMp; the enhancement was occluded by PTBP2 knockdown. We found that PTBP2 attenuation significantly favored neuron-specific alternative splicing (AS) of many genes involved in synaptic transmission, signal transduction, and axon formation. RBFOX3 knockdown significantly reversed the effect, while RBFOX3 overexpression enhanced it. The study reveals the critical role of neuron-specific AS in the direct conversion of human skin fibroblasts to neurons by showing that PTBP2 attenuation enhances this mechanism in concert with RBFOX3.
Project description:Analysis of senataxin effect on neuronal differentiation and neurite growth in RA-treated P19 cells by modulating senataxin expression levels. Senataxin silencing does not grossly affect the gene expression profiles of P19 cells At day one total RNA from Setx shRNA P19 cells, wild type human Setx P19 transfected cells with and without retionoic acid were used to compare gene expression profiling versus P19 control cells
Project description:Analysis of senataxin effect on neuronal differentiation and neurite growth in RA-treated P19 cells by modulating senataxin expression levels. Senataxin silencing does not grossly affect the gene expression profiles of P19 cells
Project description:Repressor element-1 silencing transcription factor (REST) is required for mature neurons formation. REST dysregulation underlies a key mechanism of neurodegeneration associated with neurological disorders. However, the mechanisms leading to alterations of REST-mediated silencing of key neurogenesis genes are not known. Here we show that BRAT1, a gene linked to neurodegenerative diseases, is required for activation of REST-responsive genes during neuronal-differentiation. We find that INTS11 and INTS9 subunits of Integrator complex interact with BRAT1 as a distinct trimeric complex to activate critical neuronal genes during differentiation. BRAT1 depletion results in persistence of REST residence on critical neuronal genes disrupting the differentiation of NT2 cells into astrocytes and neural cells. We identified BRAT1 and INTS11 co-occupying the promoter region of these genes and pinpoint a role for BRAT1 in recruiting INTS11 to their promoters. Disease-causing mutations in BRAT1 diminish its association with INTS11/INTS9, linking the manifestation of disease phenotypes with a defect in transcriptional activation of key neuronal genes by BRAT1/INTS11/INTS9 complex.
Project description:LIN28 is an RNA-binding protein expressed in many developing tissues. It can block let-7 microRNA processing and help promote pluripotency. We observe LIN28 expression in the developing neural tube, colocalizing with SOX2, suggesting a role in neural development. To better understand its normal developmental function, we investigated LIN28 activity during neurogliogenesis in vitro where the succession of neuronal to glial cell fates occurs as it does in vivo. LIN28 expression was high in undifferentiated cells, and was down-regulated rapidly upon differentiation. Constitutive LIN28 expression caused a complete block of gliogenesis and an increase in neurogenesis. LIN28 expression was compatible with neuronal differentiation and did not increase proliferation. LIN28 caused significant changes in gene expression prior to any effect on let-7, notably on Igf2. Furthermore, a mutant LIN28 that permitted let-7 accumulation was still able to completely block gliogenesis. Thus, at least two biological activities of LIN28 are genetically separable and may involve distinct mechanisms. LIN28 can differentially promote and inhibit specific fates and does not function exclusively by blocking let-7 family miRNAs. Importantly, LIN28âs role in cell fate succession in vertebrate cells is analogous to its activity as a developmental timing regulator in C. elegans. Two repeats of two cell lines induced to differentiate with retinoic acid/aggregation for four days. Control cells: unmodified mouse P19 embryonal carcinoma cells. Experimental cells: P19 cells constitutively expressing human LIN28A.
Project description:Viral suppressors of RNA silencing, VSRs, counteract the antiviral RNA silencing of host plants by sequestration of virus-derived siRNAs. A central question concerns whether and how VSRs associate cellular miRNAs and thus modulate plant gene expression during a viral infection. In this study we characterize the binding behaviour of the tombusviral p19 protein to miRNAs by performing an RNA-pull down experiment with bead-associated p19 protein from carnation italian ringspot virus. For this, we used cytoplasmatic extracs of Nicotiana tabacum protoplasts as an RNA source. By applying Next Generation Sequencing (NGS) to the precipitated small RNAs, we were able to identify miRNAs specifically associating with the protein and other that were not efficiently bound by p19.