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Abstract The consolidation of recent memories depends on memory replays, also called ripples, generated within the hippocampus during slow-wave sleep, and whose inactivation leads to memory impairment. For now, the mobilisation, localisation and importance of synaptic plasticity events associated to ripples are largely unknown. To tackle this question, we used cell surface AMPAR immobilisation to block post-synaptic LTP within the hippocampal region of male mice during a spatial memory task, and show that: 1- hippocampal synaptic plasticity is engaged during consolidation, but is dispensable during encoding or retrieval. 2- Plasticity blockade during sleep results in apparent forgetting of the encoded rule. 3- In vivo ripple recordings show a strong effect of AMPAR immobilisation when a rule has been recently encoded. 4- In situ investigation suggests that plasticity at CA3-CA3 recurrent synapses supports ripple generation. We thus propose that post-synaptic AMPAR mobility at CA3 recurrent synapses is necessary for ripple-dependent rule consolidation.

Integrated photonic systems require nanoscale on-chip light sources. Here Li et al., fabricate a silicon chip with LEDs smaller than the wavelength of light. This characteristic implies a partially coherent light emission, which allows the realization of an all-silicon holographic microscope.

Pruning dendritic spines requires autophagy. Here, the authors show that autophagy is required for long-term depression (LTD), a major form of synaptic plasticity. LTD induces the biogenesis of autophagic vesicles locally in dendrites to facilitate the degradation of postsynaptic proteins.

Visualisation of TARP localisation is hindered by existing imaging tools. Here the authors report a labelling and imaging platform using genetic code expansion and non-canonical amino acids; they use this to fluorescently label live neurons and localise TARP proteins using super resolution microscopy.

Long-term depression (LTD) of synaptic strength contributes to circuit remodeling, memory encoding and erasure. Here, the authors show that P2XR- and NMDAR-dependent LTD are associated with distinct and precise molecular modifications that lead to specific modification of synapse function.

During clathrin mediated endocytosis (CME), membrane scission is achieved by the concerted action of dynamin and its interacting partners such as amphiphysins. Here authors show that efficient recruitment and function of dynamin requires simultaneous binding of multiple amphiphysin SH3 domains.

Developing inhibitors that target specific protein-protein interactions (PPIs) is challenging. Here, the authors show that target selectivity and PPI blocking can be achieved simultaneously with PPI inhibitors that contain two functional modules, and create a paralog-selective PSD-95 inhibitor as proof-of-concept.

Cognitive decline in Huntington’s disease (HD) may be due to impaired hippocampal synaptic plasticity. In this study the authors show that AMPA receptor surface diffusion, a key player in synaptic plasticity, is deregulated in multiple HD mouse models as a result of impaired BDNF signalling that underlies the memory deficits, and can be pharmacologically rescued.

Existing pH-sensitive red fluorescent protein probes don’t perform well in monitoring exocytosis and endocytosis. Here, the authors combine organic dyes with self-labeling tags or antibodies to develop semisynthetic protein conjugates that can image synaptic vesicle fusion events in living cells.

How neurons produce energy to fuel fast axonal transport is only partially understood. Authors here report that most glycolytic enzymes are enriched in motile vesicles, and such glycolytic machinery can produce ATP autonomously to propel vesicle movement along microtubules in a cell-free assay.

The advent of fluorescence-based super-resolution microscopy has created a need for labeling strategies relying on small probes that minimally perturb protein function. Here the authors describe a labeling method that reduces protein tag and label sizes, allowing for accurate protein targeting and measurements of protein dynamics in tight cellular spaces.

Auxiliary AMPA receptor subunits can affect gating and surface mobility. Here the authors show that Shisa6 traps AMPA receptors at postsynaptic sites via PSD-95, and keeps them in an activated state in the presence of glutamate, preventing full desensitization and consequently synaptic depression.