ABSTRACT: We have analyzed how interaction of calcineurin with perinuclear signalosome AKAP6 affects the expression profile of transcription factors involved in cAMP/calcium signaling. We have found that calcineurin interacts with AKAP6 in calcium-dependent manner and by using anchoring disruptors, we demonstrated the importance of this interaction for depolarization-induced outgrowth of hippocampal neurons.
Project description:We have analyzed how interaction of calcineurin with perinuclear signalosome AKAP6 affects the expression profile of transcription factors involved in cAMP/calcium signaling. We have found that calcineurin interacts with AKAP6 in calcium-dependent manner and by using anchoring disruptors, we demonstrated the importance of this interaction for depolarization-induced outgrowth of hippocampal neurons.
Project description:Human genetic studies have identified the neuronal RNA binding protein, Rbfox1, as a candidate gene for autism spectrum disorders. While Rbfox1 functions as a splicing regulator in the nucleus, it is also alternatively spliced to produce cytoplasmic isoforms. To investigate cytoplasmic Rbfox1, we knocked down Rbfox proteins in mouse neurons and rescued with cytoplasmic or nuclear Rbfox1. Transcriptome profiling showed that nuclear Rbfox1 rescued splicing changes induced by knockdown, whereas cytoplasmic Rbfox1 rescued changes in mRNA levels. iCLIP-seq of subcellular fractions revealed that in nascent RNA Rbfox1 bound predominantly to introns, while cytoplasmic Rbox1 bound to 3' UTRs. Cytoplasmic Rbfox1 binding increased target mRNA stability and translation, and overlapped significantly with miRNA binding sites. Cytoplasmic Rbfox1 target mRNAs were enriched in genes involved in cortical development and autism. Our results uncover a new Rbfox1 regulatory network and highlight the importance of cytoplasmic RNA metabolism to cortical development and disease. In this data set, we included the data from RNA-seq experiments. We performed RNA-seq to profile gene expression and splicing changes. The expression levels of Rbfox1 and Rbfox3 in cultured mouse hippocampal neurons were reduced by siRNAs. The reduction of Rbfox1 and 3 was rescued by expression of cytoplasmic or nuclear Rbfox1 splice isoform. The gene expression and splicing profiles were compared between different treatments. Eight samples were analyzed.
Project description:Bipolar Disorder (BD) is a complex neuropsychiatric disorder that is characterized by intermittent episodes of mania and depression and, without treatment, 15% of patients commit suicide1. Hence, among all diseases, BD has been ranked by the WHO as a top disorder of morbidity and lost productivity2. Previous neuropathological studies have revealed a series of alterations in the brains of BD patients or animal models3, such as reduced glial cell number in the patient prefrontal cortex4, up-regulated activities of the PKA/PKC pathways5-7, and changes in dopamine/5-HT/glutamate neurotransmission systems8-11. However, the roles and causation of these changes in BD are too complex to exactly determine the pathology of the disease; none of the current BD animal models can recapitulate both the manic and depressive phenotypes or spontaneous cycling of BD simultaneously12,13. Furthermore, while some patients show remarkable improvement with lithium treatment, for yet unknown reasons, other patients are refractory to lithium treatment. Therefore, developing an accurate and powerful biological model has been a challenge for research into BD. The development of induced pluripotent stem cell (iPSC) technology has provided such a new approach. Here, we developed a human BD iPSC model and investigated the cellular phenotypes of hippocampal dentate gyrus neurons derived from the patient iPSCs. Using patch clamp recording, somatic Ca2+ imaging and RNA-seq techniques, we found that the neurons derived from BD patients exhibited hyperactive action potential (AP) firing, up-regulated expression of PKA/PKC/AP and mitochondria-related genes. Moreover, lithium selectively reversed these alterations in the neurons of patients who responded to lithium treatment. Therefore, hyper-excitability is one endophenotype of BD that is probably achieved through enhancement in the PKA/PKC and Na+ channel signaling systems, and our BD iPSC model can be used to develop new therapies and drugs aimed at clinical treatment of this disease. total RNAseq from neurons generated from BD patient-specific iPS cells
Project description:Primary cultured hippocampal neurons were infected with lentiviral particles bearing constitutively active versions of the transcription factors CREB, SRF, EGR1 and FOS to define the downstream genetic program associated with each of these paradigmatic transcription factors in neurons. For CREB, we also extracted samples at a shorter infection time to try to dissect the different components of the wider genetic response observed upon expression of a constitutively active version of this transcription factor. In order to further explore the contribution of these transcriptional regulators to activity-driven gene expression, we also treated cultured hippocampal neurons infected with GFP-only expressing lentiviral particles with different drugs (bicuculline, forskokine, and BDNF) and profiled the associated transcriptional response. Finally, in order to further explore the role of CREB in forskolin-mediated gene expression, we also used A-CREB, a dominant negative form of this transcription factor. Specifically, we stimulated neurons with forskolin in the presence or absence of lentiviral particles expressing A-CREB and carried out genome-wide transcriptional profiling.
Project description:The subcellular localization and translation of messenger RNA (mRNA) supports functional differentiation between cellular compartments. In neuronal dendrites, local translation of mRNA provides a rapid and specific mechanism for synaptic plasticity and memory formation, and might be involved in the pathophysiology of certain brain disorders. Despite the importance of dendritic mRNA translation, little is known about which mRNAs can be translated in dendrites in vivo and when their translation occurs. Here we collect ribosome-bound mRNA from the dendrites of CA1 pyramidal neurons in the adult mouse hippocampus. We find that dendritic mRNA rapidly associates with ribosomes following a novel experience consisting of a contextual fear conditioning trial. High throughput RNA sequencing followed by machine learning classification reveals an unexpected breadth of ribosome-bound dendritic mRNAs, including mRNAs expected to be entirely somatic. Our findings are in agreement with a mechanism of synaptic plasticity that engages the acute local translation of functionally diverse dendritic mRNAs. RNA-Seq of ribosome-bound mRNA immunoprecipitated from dendrites and soma of CA1 pyramidal neurons in the mouse hippocampus
Project description:Microarray expression profilling of mouse primary mixed cortical/hippocampal neurons, primary fibroblasts and L929 cells to compare ISGs signature in disctinct cell types Primary mixed cortical/hippocampal neurons, primary fibroblasts (MEFs) and L929 cells were mock-treated or treated with 5U/mL of IFN-beta and RNA was harvested after 24 hours. For neurons and fibroblast, 2 samples were analyzed for each condition.
Project description:Transcriptome profiling of rat primary hippocampal neurons when the dyslexia candidate gene DCDC2 is overexpressed using transient transfections.<br><br>Additional processed data files and their associated custom CDF are available on the FTP site for this experiment.
Project description:The present study has used whole-rat genome microarray expression profiling to identify genes whose expression is significantly altered in hippocampal neuronal cultures submitted to oxygen and glucose deprivation (OGD), an established in vitro model for cerebral global ischemia that is suitable for investigations at the molecular level. To do so, total RNA was extracted from hippocampal neuronal cultures at an early (7h) and delayed (24h) time point after OGD, as well as from control neurons. Analysis of gene ontology showed that OGD followed by 7h or 24h of recovery induces changes in the expression levels of genes related with inflammation, response to oxidative stress, metabolism, apoptosis, synaptic proteins and ion channels and, importantly, genes that show different expression levels are mainly specific to one of the two time points of recovery analyzed. The expression levels of several genes were confirmed by qPCR and were in good agreement with the microarray data, showing that the combined use of the OGD model and the microarray technology can be a useful tool for the study molecular mechanisms contributing to the neuronal demise after transient global ischemia. Ischemia induced gene expression in primary hippocampal neuronal rat cultures was measured at 7 and 24 hours after exposure to Oxygen and Glucose deprivation (OGD). Three independent experiments were performed at each time (7 or 24 hours) as independent biological replicates.
Project description:FUS is a primarily nuclear RNA-binding protein with important roles in RNA processing and transport. FUS mutations disrupting its nuclear localization characterize a subset of amyotrophic lateral sclerosis (ALS-FUS) patients, through an unidentified pathological mechanism. FUS regulates nuclear RNA, but its role at the synapse is poorly understood. Here, we used super-resolution imaging to determine the physiological localization of extranuclear, neuronal FUS and found it predominantly near the vesicle reserve pool of presynaptic sites. Using CLIP-seq on synaptoneurosome preparations, we identified synaptic RNA targets of FUS that are associated with synapse organization and plasticity. Synaptic FUS was significantly increased in a knock-in mouse model of ALS-FUS, at presymptomatic stages. Despite apparently unaltered synaptic organization, RNA-seq of synaptoneurosomes highlighted age-dependent dysregulation of glutamatergic and GABAergic synapses. Our study indicates that FUS relocalization to the synapse in early stages of ALS-FUS results in synaptic impairment, potentially representing an initial trigger of neurodegeneration.