Exocytosis and endocytosis are essential processes that allow bidirectional exchanges between intracellular compartments and the neuronal membrane. While at the presynaptic level, the exocytosis and endocytosis mediating neurotransmitter release have been extensively characterized, at postsynaptic level much less is known.
Over the last decades, a number of studies have demonstrated that the insertion and removal of neurotransmitter receptors to and from the postsynaptic plasma membrane are key regulators of the number of receptors incorporated at the synapse, providing compelling evidence that those processes shape synaptic function and plasticity. The advent of sophisticated imaging approaches, such as live cell spinning disk confocal microscopy, total internal reflection fluorescence microscopy (TIRFM), single molecule localization microscopy (SMLM) or stimulated emission depletion (STED) and novel reagents (e.g. pH-sensitive fluorescent proteins, dyes and Quantum Dots, chemical and photo-activated hooks that target proteins to specific organelles) has also allowed for the detection and characterization of these crucial steps at the postsynaptic neuronal membrane.
Nevertheless, several aspects of the exocytosis and endocytosis processes remain to be fully elucidated such as: i) where do these events occur with respect to the postsynaptic density and ii) with which kinetics; iii) what is their molecular machinery; iv) how are they regulated by neuronal activity; v) what is their physiological impact on synaptic function and plasticity. Importantly, these questions do not exclusively pertain to neurotransmitter receptors, but also to neuromodulator receptors and all surface synaptic proteins. Filling those gaps of knowledge would set the ground for addressing major and broader open questions in the field of the molecular and cellular neuroscience. For instance, which are the rules that sustain and limit exo/endocytosis over time? How do those processes differ at the somatic level and along the dendritic arborization? Which are the molecular sorting operations that govern the accuracy of proteins endocytic and secretory routes? How does the cargo-specificity of exo/endosomes define the location and kinetics of those processes? How can we achieve a real time monitoring of exo/endocytosis in vivo to assess their acute and long-term impact on neuronal function?
The purpose of this Research Topic is to collect comprehensive and recent views of the exocytosis, endocytosis and recycling events occurring at the postsynaptic neuronal membrane. We welcome the submission of papers (primary research articles, reviews, commentaries, technique reports) focusing on postsynaptic exocytosis, endocytosis and recycling from different angles, ranging from the molecular and cellular mechanisms controlling secretory pathways and post endocytic sorting, to the impact of those processes on synaptic function and plasticity. Manuscripts addressing dendritic transport, surface turnover and intracellular fate of postsynaptic proteins are in line with the scope of the present Research Topic. We also encourage the submission of more biophysically-oriented studies focusing on the regulation of membrane fusion events, as well as technical papers indicating novel approaches to study those processes. Moreover, manuscripts exploring how the exocytosis and endocytosis of proteins (other than neurotransmitter receptors) and molecules (such as retrograde messengers released postsynaptically) contribute to synaptic function are welcome.
Exocytosis and endocytosis are essential processes that allow bidirectional exchanges between intracellular compartments and the neuronal membrane. While at the presynaptic level, the exocytosis and endocytosis mediating neurotransmitter release have been extensively characterized, at postsynaptic level much less is known.
Over the last decades, a number of studies have demonstrated that the insertion and removal of neurotransmitter receptors to and from the postsynaptic plasma membrane are key regulators of the number of receptors incorporated at the synapse, providing compelling evidence that those processes shape synaptic function and plasticity. The advent of sophisticated imaging approaches, such as live cell spinning disk confocal microscopy, total internal reflection fluorescence microscopy (TIRFM), single molecule localization microscopy (SMLM) or stimulated emission depletion (STED) and novel reagents (e.g. pH-sensitive fluorescent proteins, dyes and Quantum Dots, chemical and photo-activated hooks that target proteins to specific organelles) has also allowed for the detection and characterization of these crucial steps at the postsynaptic neuronal membrane.
Nevertheless, several aspects of the exocytosis and endocytosis processes remain to be fully elucidated such as: i) where do these events occur with respect to the postsynaptic density and ii) with which kinetics; iii) what is their molecular machinery; iv) how are they regulated by neuronal activity; v) what is their physiological impact on synaptic function and plasticity. Importantly, these questions do not exclusively pertain to neurotransmitter receptors, but also to neuromodulator receptors and all surface synaptic proteins. Filling those gaps of knowledge would set the ground for addressing major and broader open questions in the field of the molecular and cellular neuroscience. For instance, which are the rules that sustain and limit exo/endocytosis over time? How do those processes differ at the somatic level and along the dendritic arborization? Which are the molecular sorting operations that govern the accuracy of proteins endocytic and secretory routes? How does the cargo-specificity of exo/endosomes define the location and kinetics of those processes? How can we achieve a real time monitoring of exo/endocytosis in vivo to assess their acute and long-term impact on neuronal function?
The purpose of this Research Topic is to collect comprehensive and recent views of the exocytosis, endocytosis and recycling events occurring at the postsynaptic neuronal membrane. We welcome the submission of papers (primary research articles, reviews, commentaries, technique reports) focusing on postsynaptic exocytosis, endocytosis and recycling from different angles, ranging from the molecular and cellular mechanisms controlling secretory pathways and post endocytic sorting, to the impact of those processes on synaptic function and plasticity. Manuscripts addressing dendritic transport, surface turnover and intracellular fate of postsynaptic proteins are in line with the scope of the present Research Topic. We also encourage the submission of more biophysically-oriented studies focusing on the regulation of membrane fusion events, as well as technical papers indicating novel approaches to study those processes. Moreover, manuscripts exploring how the exocytosis and endocytosis of proteins (other than neurotransmitter receptors) and molecules (such as retrograde messengers released postsynaptically) contribute to synaptic function are welcome.
