Biology subjects

De Luca, P.

Publications and source records attributed to De Luca, P..

3 recordsLinked to original sources

bioRxiv2026

Minos transposon-mediated transgenesis in the sea urchin Paracentrotus lividus

In the multitude of suitable experimental systems used for functional studies in the field of developmental biology, the sea urchin plays a central role due to its amenability to various methods, including both transient and stable transgenesis. Among others, transposable elements represent powerful tools for generating stable transgenic specimens, and Minos transposon turned out to be an excellent genetic tool in marine organisms, despite its efficiency being host-dependent. This study provides new evidence for the activity of Minos transposable elements and their stable integration into the genome of the Mediterranean sea urchin Paracentrotus lividus. Using the Minos-based technology coupled with a fully-automated system used for the qPCR screening of the Minos transposon integration, we devised a new pipeline for performing transgenesis-based functional studies in P. lividus.

molecular biology↗

bioRxiv2025

BDNF-TrkB signaling promotes synaptic GluN2A-NMDA receptor expression and network hyperexcitability in cultured hippocampal neurons and during status epilepticus

Brain-derived neurotrophic factor (BDNF) is a key modulator of synaptic function, acting through activation of TrkB receptors. This neurotrophic factor mediates synaptic plasticity and plays an important role in epileptogenesis, but the underlying molecular mechanisms have not been fully elucidated. In this work, we investigated the role of BDNF-TrkB signaling in the regulation of synaptic GluN2A-containing NMDA receptors (NMDAR), and the impact on network synchronization in cultured hippocampal neurons. Incubation with BDNF increased the synaptic surface expression of GluN2A-containing NMDAR in rat hippocampal synaptoneurosomes and in cultured hippocampal neurons. The effect in the latter preparation was time-dependent and required new protein synthesis. Mechanistically, we identified a signaling cascade involving hnRNPK, the non-receptor tyrosine kinase Pyk2, and protein kinase C (PKC) as essential for mediating BDNF-induced upregulation in the synaptic expression of GluN2A-containing NMDAR. Knockdown of hnRNPK or Pyk2, pharmacological inhibition of PKC, or expression of a phosphorylation -deficient Pyk2 mutant abolished BDNF-induced synaptic surface accumulation of Glu2A. Moreover, Pyk2 phosphorylation at Y402 was necessary for both basal and BDNF-induced synaptic GluN2A expression. Functional multielectrode array (MEA) recordings showed that endogenous BDNF and GluN2A-containing NMDAR contributed to the increase in network activity in cultured hippocampal neurons evoked by stimulation with a cocktail including bicuculline, 4-aminopyridine, and glycine. Importantly, BDNF-TrkB signaling also mediated the upregulation in the hippocampal synaptic surface expression of GluN2A-containing NMDAR, as determined in rats subjected to the pilocarpine model of temporal lobe epilepsy, where increased GluN2A synaptic expression was observed and shown to be TrkB-dependent. These findings unveil a crucial BDNF/TrkB-PKC-Pyk2-hnRNPK signaling axis that regulates synaptic GluN2A levels and network excitability, offering novel insights into the molecular basis of synaptic plasticity.

neuroscience↗

bioRxiv2024

Synaptic accumulation of GluN2B-containing NMDA receptors mediates the effects of BDNF-TrkB signalling on synaptic plasticity and in epileptogenesis

Brain-derived neurotrophic factor (BDNF) is a key mediator of synaptic plasticity and memory formation in the hippocampus. However, the BDNF-induced alterations in the glutamate receptors coupled to the plasticity of glutamatergic synapses in the hippocampus have not been elucidated. In this work we investigated the putative role of GluN2B-containing NMDA receptors in the plasticity of glutamatergic synapses induced by BDNF. Stimulation of hippocampal synaptoneurosomes with BDNF led to a significant time-dependent increase in the synaptic surface expression of GluN2B-containing NMDA receptors as determined by immunocytochemistry with colocalization with pre- (vesicular glutamate transporter) and post-synaptic markers (PSD95). Similarly, BDNF induced the synaptic accumulation of GluN2B-containing NMDA receptors at the synapse in cultured hippocampal neurons, by a mechanism sensitive to the PKC inhibitor G[O]6983. The effects of PKC may be mediated by phosphorylation of Pyk2, as suggested by western blot experiments analyzing the phosphorylation of the kinase on Tyrosine 402. GluN2B-containing NMDA receptors mediated the effects of BDNF in the facilitation of the early phase of long-term potentiation (LTP) of hippocampal CA1 synapses induced by {theta}-burst stimulation, since the effect of the neurotrophin was abrogated in the presence of the GluN2B inhibitor Co 101244. In the absence of BDNF, the GluN2B inhibitor did not effect LTP. Surface accumulation of GluN2B-containing NMDA receptors was also observed in hippocampal synaptoneurosomes isolated from rats subjected to the pilocarpine model of temporal lobe epilepsy, after reaching Status epilepticus, an effect that was inhibited by administration of the TrkB receptor inhibitor ANA-12. Together, these results show that the synaptic accumulation of GluN2B-containing NMDA receptors mediate the effects of BDNF in the plasticity of glutamatergic synapses in the hippocampus.

neuroscience↗