8 documents found, page 1 of 1
Transient incubation of cultured hippocampal neurons in the absence of magnesiu...
Mele, Miranda; Vieira, Ricardo; Correia, Bárbara; Luca, Pasqualino De; Duarte, Filipe V.; Pinheiro, Paulo S.; Duarte, Carlos B.Cell culture models are important tools to study epileptogenesis mechanisms. The aim of this work was to characterize the spontaneous and synchronized rhythmic activity developed by cultured hippocampal neurons after transient incubation in zero Mg2+ to model Status Epilepticus. Cultured hippocampal neurons were transiently incubated with a Mg2+-free solution and the activity of neuronal networks was evaluated ...
Synaptogenesis Stimulates a Proteasome-Mediated Ribosome Reduction in Axons
Costa, Rui O.; Martins, Helena; Martins, Luís F.; Cwetsch, Andrzej W; Mele, Miranda; Pedro, Joana R.; Tomé, Diogo; Jeon, Noo Li; Cancedda, LauraRibosomes and a subset of cellular mRNAs are trafficked into axons of developing neurons. The axonal localization of translational machinery allows new proteins to be rapidly and locally synthesized during axonal growth and pathfinding. However, in mature neurons, axonal ribosomes are significantly reduced or even absent. The mechanism that elicits this removal is currently unknown. Here, we demonstrate that sy...
Alterations in GABAA-Receptor Trafficking and Synaptic Dysfunction in Brain Dis...
Mele, Miranda; Costa, Rui O.; Duarte, Carlos B.GABAA receptors (GABAAR) are the major players in fast inhibitory neurotransmission in the central nervous system (CNS). Regulation of GABAAR trafficking and the control of their surface expression play important roles in the modulation of the strength of synaptic inhibition. Different pieces of evidence show that alterations in the surface distribution of GABAAR and dysregulation of their turnover impair the a...
The RNA-Binding Protein hnRNP K Mediates the Effect of BDNF on Dendritic mRNA M...
Leal, Graciano; Comprido, Diogo; Luca, Pasqualino De; Morais, Eduardo Manuel Firmo; Rodrigues, Luís; Mele, Miranda; Santos, Ana R.; Costa, Rui O.Brain-derived neurotrophic factor (BDNF) is an important mediator of long-term synaptic potentiation (LTP) in the hippocampus. The local effects of BDNF depend on the activation of translation activity, which requires the delivery of transcripts to the synapse. In this work, we found that neuronal activity regulates the dendritic localization of the RNA-binding protein heterogeneous nuclear ribonucleoprotein K ...
The RNA-binding protein hnRNP K mediates the effect of BDNF on dendritic mRNA m...
Leal, Graciano; Comprido, Diogo; Luca, Pasqualino de; Morais, Eduardo; Rodrigues, Luís; Mele, Miranda; Santos, Ana R.; Costa, Rui O.; Pinto, Maria JoanaBrain-derived neurotrophic factor (BDNF) is an important mediator of long-term synaptic potentiation (LTP) in the hippocampus. The local effects of BDNF depend on the activation of translation activity, which requires the delivery of transcripts to the synapse. In this work, we found that neuronal activity regulates the dendritic localization of the RNA-binding protein heterogeneous nuclear ribonucleoprotein K ...
Differential role of the proteasome in the early and late phases of BDNF-induce...
Santos, Ana Rita; Mele, Miranda; Vaz, Sandra H.; Kellermayer, Blanka; Grimaldi, Maddalena; Oliveira, Mariana; Rombo, Diogo M.; Comprido, DiogoThe neurotrophin brain-derived neurotrophic factor (BDNF) mediates activity-dependent long-term changes of synaptic strength in the CNS. The effects of BDNF are partly mediated by stimulation of local translation, with consequent alterations in the synaptic proteome. The ubiquitin-proteasome system (UPS) also plays an important role in protein homeostasis at the synapse by regulating synaptic activity. However,...
GABAA receptor dephosphorylation followed by internalization is coupled to neur...
Mele, Miranda; Ribeiro, Luís; Inácio, Ana R.; Wieloch, Tadeusz; Duarte, C. B.Cerebral ischemia is characterized by an early disruption of GABAergic neurotransmission contributing to an imbalance of the excitatory/inhibitory equilibriumand neuronal death, but the molecular mechanisms involved are not fully understood. Here we report a downregulation of GABAA receptor (GABAAR) expression, affecting both mRNA and protein levels of GABAAR subunits, in hippocampal neurons subjected to oxygen...
BDNF regulates the expression and distribution of vesicular glutamate transport...
Melo, Carlos V.; Mele, Miranda; Curcio, Michele; Comprido, Diogo; Silva, Carla G.; Duarte, Carlos B.BDNF is a pro-survival protein involved in neuronal development and synaptic plasticity. BDNF strengthens excitatory synapses and contributes to LTP, presynaptically, through enhancement of glutamate release, and postsynaptically, via phosphorylation of neurotransmitter receptors, modulation of receptor traffic and activation of the translation machinery. We examined whether BDNF upregulated vesicular glutamate...