Blobby is a synaptic active zone assembly protein required for memory in Drosophila.

At presynaptic active zones (AZs), scaffold proteins are critical for coordinating synaptic vesicle release and forming essential nanoarchitectures. However, regulatory principles steering AZ scaffold assembly, function, and plasticity remain insufficiently understood. We here identify an additional Drosophila AZ protein, "Blobby", essential for proper AZ nano-organization.

Spermidine is essential for fasting-mediated autophagy and longevity.

Caloric restriction and intermittent fasting prolong the lifespan and healthspan of model organisms and improve human health. The natural polyamine spermidine has been similarly linked to autophagy enhancement, geroprotection and reduced incidence of cardiovascular and neurodegenerative diseases across species borders. Here, we asked whether the cellular and physiological consequences of caloric restriction and fasting depend on polyamine metabolism.

Presynaptic Precursor Vesicles-Cargo, Biogenesis, and Kinesin-Based Transport across Species.

The faithful formation and, consequently, function of a synapse requires continuous and tightly controlled delivery of synaptic material. At the presynapse, a variety of proteins with unequal molecular properties are indispensable to compose and control the molecular machinery concerting neurotransmitter release through synaptic vesicle fusion with the presynaptic membrane. As presynaptic proteins are produced mainly in the neuronal soma, they are obliged to traffic along microtubules through the axon to reach the consuming presynapse.

Interactive nanocluster compaction of the ELKS scaffold and Cacophony Ca channels drives sustained active zone potentiation.

At presynaptic active zones (AZs), conserved scaffold protein architectures control synaptic vesicle (SV) release by defining the nanoscale distribution and density of voltage-gated Ca channels (VGCCs). While AZs can potentiate SV release in the minutes range, we lack an understanding of how AZ scaffold components and VGCCs engage into potentiation. We here establish dynamic, intravital single-molecule imaging of endogenously tagged proteins at AZs undergoing presynaptic homeostatic potentiation.

Spermidine reduces neuroinflammation and soluble amyloid beta in an Alzheimer's disease mouse model.

Background: Deposition of amyloid beta (Aβ) and hyperphosphorylated tau along with glial cell-mediated neuroinflammation are prominent pathogenic hallmarks of Alzheimer's disease (AD). In recent years, impairment of autophagy has been identified as another important feature contributing to AD progression. Therefore, the potential of the autophagy activator spermidine, a small body-endogenous polyamine often used as dietary supplement, was assessed on Aβ pathology and glial cell-mediated neuroinflammation.

Translational control of polyamine metabolism by CNBP is required for locomotor function.

Microsatellite expansions of CCTG repeats in the cellular nucleic acid-binding protein () gene leads to accumulation of toxic RNA and have been associated with myotonic dystrophy type 2 (DM2). However, it is still unclear whether the dystrophic phenotype is also linked to CNBP decrease, a conserved CCHC-type zinc finger RNA-binding protein that regulates translation and is required for mammalian development. Here, we show that depletion of CNBP in muscles causes ageing-dependent locomotor defects that are correlated with impaired polyamine metabolism.

Rab2 regulates presynaptic precursor vesicle biogenesis at the trans-Golgi.

Reliable delivery of presynaptic material, including active zone and synaptic vesicle proteins from neuronal somata to synaptic terminals, is prerequisite for successful synaptogenesis and neurotransmission. However, molecular mechanisms controlling the somatic assembly of presynaptic precursors remain insufficiently understood. We show here that in mutants of the small GTPase Rab2, both active zone and synaptic vesicle proteins accumulated in the neuronal cell body at the trans-Golgi and were, consequently, depleted at synaptic terminals, provoking neurotransmission deficits.

Antagonistic interactions between two Neuroligins coordinate pre- and postsynaptic assembly.

As a result of developmental synapse formation, the presynaptic neurotransmitter release machinery becomes accurately matched with postsynaptic neurotransmitter receptors. Trans-synaptic signaling is executed through cell adhesion proteins such as Neurexin::Neuroligin pairs but also through diffusible and cytoplasmic signals. How exactly pre-post coordination is ensured in vivo remains largely enigmatic.

RIM-binding protein couples synaptic vesicle recruitment to release sites.

At presynaptic active zones, arrays of large conserved scaffold proteins mediate fast and temporally precise release of synaptic vesicles (SVs). SV release sites could be identified by clusters of Munc13, which allow SVs to dock in defined nanoscale relation to Ca2+ channels. We here show in Drosophila that RIM-binding protein (RIM-BP) connects release sites physically and functionally to the ELKS family Bruchpilot (BRP)-based scaffold engaged in SV recruitment.

Ultrafast, temporally stochastic STED nanoscopy of millisecond dynamics.

Electro-optical scanning (>1,000 frames/s) with pixel dwell times on the order of the lifetime of the fluorescent molecular state renders stimulated emission depletion (STED) nanoscopy temporally stochastic. Photon detection from a molecule occurs stochastically in one of several scanning frames, and the spatial origin of the photon is known with subdiffraction precision. Images are built up by binning consecutive frames, making the time resolution freely adjustable.