ABSTRACT: Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory. 12 hippocampal cell culture samples analysed, 3 coverslips pooled per sample. Treatments are as follows: Block: an inhibitor cocktail containing 50 µM D-APV, 40 µM CNQX, and 100 nM TTX for 3 hrs Activity: 50 µM bicuculline (BiC)/500 µM 4-Aminopyridine ActD: 25 µM actinomycin D
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory. 12 hippocampal cell culture samples analysed, 3 coverslips pooled per sample. Treatments are as follows: Block: an inhibitor cocktail containing 50 µM D-APV, 40 µM CNQX, and 100 nM TTX for 3 hrs Activity: 50 µM bicuculline (BiC)/500 µM 4-Aminopyridine ActD: 25 µM actinomycin D
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory. 12 hippocampal cell culture samples analysed, 3 coverslips pooled per sample. Treatments are as follows: Block: an inhibitor cocktail containing 50 µM D-APV, 40 µM CNQX, and 100 nM TTX for 3 hrs Activity: 50 µM bicuculline (BiC)/500 µM 4-Aminopyridine ActD: 25 µM actinomycin D
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory. 4 samples analysed, 3 coverslips pooled per sample. Mouse DRG neuron cell bodies and axons were separated in multicompartment cell cultures allowing electrical stimulation of axons, growing under a high-resistance partition between compartments, through platinum electrodes in the lid of the culture dish (Reference: http://www.ncbi.nlm.nih.gov/pubmed/9295372)
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory.
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory.
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory.
Project description:Ongoing neuronal activity during development and plasticity acts to refine synaptic connections and contributes to the induction of plasticity and ultimately long term memory storage. Activity-dependent post-transcriptional control of mRNAs occurs through transport to axonal and dendritic compartments, local translation, and mRNA stability. We have identified a mechanism that contributes to activity-dependent regulation of mRNA stability during synaptic plasticity. In this study we demonstrate rapid, post-transtriptional control over process-enriched mRNAs by neuronal activity. Systematic analysis of the 3'-UTRs of destablized transcripts, identifies enrichment in sequence motifs corresponding to miRNA binding sites. The miRNAs that were identified, miR-326-3p/miR-330-5p, miR-485-5p, miR-666-3p, and miR-761 are predicted to regulate networks of genes important in plasticity and development. We find that these miRNAs are developmentally regulated in the hippocampus, many increasing by postnatal day 14. We further show that miR-485-5p controls NGF-induced neurite outgrowth in PC12 cells, tau expression, and axonal development in hippocampal neurons. miRNAs can function at the synapse to rapidly control and affect short- and long-term changes at the synapse. These processes likely occur during refinement of synaptic connections and contribute to the induction of plasticity and learning and memory.
Project description:Homeostatic synaptic plasticity (HSP) is a fundamental neuronal mechanism that allows networks to compensate for prolonged changes in activity by adjusting synaptic strength. This process is crucial for maintaining stable brain function and has been implicated in memory consolidation during sleep. While scaling of both excitatory and inhibitory synapses plays an important role during homeostatic synaptic plasticity, molecules coordinating both of these processes are unknown. In this study, we investigate the role of miR-218-5p as a regulator of inhibitory and excitatory synapses in the context of picrotoxin (PTX)-induced homeostatic synaptic downscaling (HSD) in rat hippocampal neurons. Using enrichment analysis of miRNA-binding sites in differentially expressed genes changing upon PTX-induced HSD, we bioinformatically predicted and experimentally validated increased miR-218-5p activity upon PTX-treatment in the process compartment. By monitoring synapse structure in vitro with confocal microscopy, we demonstrate that miR-218-5p exerts a dual effect in HSD: it prevents the downscaling of excitatory synapses and dendritic spines, while at the same time blocking inhibitory synapse upscaling. Furthermore, we identify the Neuroligin2 interacting molecule Mdga1 as a crucial target of miR-218-5p in the context of homeostatic upscaling of inhibitory synapses. By performing long-term electroencephalographic (EEG) recordings, we further revealed that local inhibition of miR-218-5p in the somatosensory cortex reduced local slow-wave activity (SWA) during non-rapid-eye-movement (NREM) sleep. In summary, this study uncovers miR-218-5p as a key player in coordinating inhibitory and excitatory synapses during homeostatic plasticity and sleep. Our findings contribute to a deeper understanding of how neural circuits maintain stability in the face of activity-induced perturbations, with potential implications for both physiological and pathological conditions.
Project description:Mammalian target of rapamycin (mTOR) is implicated in synaptic plasticity and local translation in dendrites. Here we found that the mTOR inhibitor, rapamycin, increased the Kv1.1 voltage-gated potassium channel protein in hippocampal neurons and promoted Kv1.1 surface expression on dendrites without altering its axonal expression. Moreover, endogenous Kv1.1 mRNA was detected in dendrites. Using Kv1.1 fused to the photo-convertible fluorescence protein Kaede as a reporter for local synthesis, we observed Kv1.1 synthesis in dendrites upon inhibition of mTOR or the N-methyl-D-aspartate (NMDA) glutamate receptor. Thus, synaptic excitation may cause local suppression of dendritic Kv1 channels by reducing their local synthesis. Experiment Overall Design: mRNA isoloated from the synaptosomes of the hippocampus is compared to mRNA isolated from the total hippocampus to identify mRNAs that are enriched at the synapse
Project description:Drug-induced alterations in gene expression play an important role in the development of addictive behavior. Methionine has been proven to inhibit addictive behaviors of cocaine dependence. However, the mechanisms underlying how methionine use corresponds to drug-induced behaviors still remain unclear. We performed mRNA and miRNA high-throughput sequencing of the prefrontal cortex in a mouse model of cocaine CPP combined with L-methionine in order to identify L-methionine target miRNAs and genes that participate in the cocaine conditioned place preference (CPP). We found that the L-methionine inhibits cocaine CPP. Sequencing data analysis showed that L-methionine down-regulates genes enriched in the Glutamatergic Synapse pathways and significantly reversed the cocaine-induced expression changes of the substance dependence pathways (Morphine addiction and Nicotine addiction) and the neurotransmitter synapse pathways (Glutamatergic Synapse, Cholinergic Synapse and GABAergic Synapse). Furthermore, the Glutamatergic synapse was either overlapped between DEGs with DEGs-miRNA induced by cocaine CPP, or with the MET effects on cocaine CPP. Nineteen targeted genes were investigated and five were identified (Gria4, Grid1, Grik4, Grik5 and Grin3a) to belong to iGluR family. Interestingly, there were several miRNAs that had the same sequence which targets the iGluR family: Mmu-miR-30e-50p and mmu-miR-380-5p share UUGAC motif and targets Grik4; mmu-miR-6940-3p and mmu-miR-212-5p both share UGGCU motif which targets Gria4 and Grid1 respectively. Thus, we demonstrated the efficacy of L-methionine in counteracting the effects of cocaine CPP and identified specific genes of synaptic plasticity pathways, especially the Glutamatergic synapse pathway, which is modulated by L-methionine in response to cocaine dependence.