Presynaptic sensor and silencer of peptidergic transmission reveal neuropeptides as primary transmitters in pontine fear circuit

Cell, Год журнала: 2024, Номер 187(18), С. 5102 - 5117.e16

Опубликована: Июль 22, 2024

Язык: Английский

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Presynaptic perspective: Axonal transport defects in neurodevelopmental disorders

The Journal of Cell Biology, Год журнала: 2024, Номер 223(6)

Опубликована: Апрель 3, 2024

Disruption of synapse assembly and maturation leads to a broad spectrum neurodevelopmental disorders. Presynaptic proteins are largely synthesized in the soma, where they packaged into precursor vesicles transported distal axons ensure precise maintenance presynapses. Due their morphological features, neurons face challenges delivery presynaptic cargos nascent boutons. Thus, targeted axonal transport is vital build functional synapses. A growing number mutations genes encoding machinery have been linked Emerging lines evidence started uncover mechanisms underlying defects, thus broadening view disorders beyond postsynaptic mechanisms. In this review, we discuss perspectives by focusing on impaired disturbed We also potential strategies for restoring as an early therapeutic intervention.

Язык: Английский

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Differential axonal trafficking of Neuropeptide Y-, LAMP1-, and RAB7-tagged organelles in vivo

eLife, Год журнала: 2022, Номер 11

Опубликована: Дек. 2, 2022

Different organelles traveling through neurons exhibit distinct properties in vitro, but this has not been investigated the intact mammalian brain. We established simultaneous dual color two-photon microscopy to visualize trafficking of Neuropeptide Y (NPY)-, LAMP1-, and RAB7-tagged thalamocortical axons imaged mouse cortex vivo. This revealed that LAMP1- move significantly faster than NPY-tagged both anterograde retrograde direction. NPY traveled more selectively direction LAMP1 RAB7. By using a synapse marker calcium sensor, we further transport dynamics organelles. found these slow down pause at synapses. In contrast previous vitro studies, significant increase speed was observed after spontaneous activity elevated levels vivo as well electrically stimulated acute brain slices. Together, show remarkable diversity speeds three axonal organelle differ from previously vitro.

Язык: Английский

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Rab10 regulates neuropeptide release by maintaining Ca2+ homeostasis and protein synthesis

Опубликована: Янв. 6, 2025

Dense core vesicles (DCVs) transport and release various neuropeptides neurotrophins that control diverse brain functions, but the DCV secretory pathway remains poorly understood. Here, we tested a prediction emerging from invertebrate studies about crucial role of intracellular trafficking GTPase Rab10, by assessing exocytosis at single-cell resolution upon acute Rab10 depletion in mature mouse hippocampal neurons, to circumvent potential confounding effects Rab10’s established neurite outgrowth. We observed significant inhibition Rab10-depleted whereas synaptic vesicle was unaffected. However, rather than direct involvement trafficking, this effect attributed two ER-dependent processes, ER-regulated Ca 2+ dynamics protein synthesis. Gene ontology analysis differentially expressed proteins identified substantial alterations ER/ribosomal proteins, including -pump SERCA2. In addition, ER morphology were altered, levels depleted homeostasis impaired neurons. entry using ionophore still triggered less exocytosis. Instead, leucine supplementation, which enhances synthesis, largely rescued deficiency. conclude is required for neuropeptide maintaining regulating Furthermore, appeared more dependent on (acute) synthesis

Язык: Английский

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Rab10 regulates neuropeptide release by maintaining Ca2+ homeostasis and protein synthesis

eLife, Год журнала: 2025, Номер 13

Опубликована: Апрель 2, 2025

Dense core vesicles (DCVs) transport and release various neuropeptides neurotrophins that control diverse brain functions, but the DCV secretory pathway remains poorly understood. Here, we tested a prediction emerging from invertebrate studies about crucial role of intracellular trafficking GTPase Rab10, by assessing exocytosis at single-cell resolution upon acute Rab10 depletion in mature mouse hippocampal neurons, to circumvent potential confounding effects Rab10’s established neurite outgrowth. We observed significant inhibition Rab10-depleted whereas synaptic vesicle was unaffected. However, rather than direct involvement trafficking, this effect attributed two ER-dependent processes, ER-regulated Ca 2+ dynamics, protein synthesis. Gene Ontology analysis differentially expressed proteins identified substantial alterations ER/ribosomal proteins, including pump SERCA2. In addition, ER morphology dynamics were altered, levels depleted, homeostasis impaired neurons. entry using ionophore still triggered less exocytosis. Instead, leucine supplementation, which enhances synthesis, largely rescued deficiency. conclude is required for neuropeptide maintaining regulating Furthermore, appeared more dependent on (acute) synthesis

Язык: Английский

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RIM and MUNC13 membrane–binding domains are essential for neuropeptide secretion

The Journal of Cell Biology, Год журнала: 2025, Номер 224(7)

Опубликована: Май 12, 2025

Neurons release neurotransmitters from synaptic vesicles (SVs) and neuropeptides dense-core (DCVs). The presynaptic proteins RIM MUNC13 play key roles in both pathways. It remains unclear how DCVs are targeted to sites whether involved this process. Here, we show that three membrane-binding domains regulate DCV exocytosis differently SV exocytosis. Using neuropeptide secretion assays with single-vesicle resolution peptidomics analysis of endogenous MUNC13/RIM null neurons, demonstrate is essential for N terminus prevents degradation via the proteasome, inhibiting proteasomal partially rescues RIM’s absence. Unlike exocytosis, PIP2-binding C2B domain C1-C2B polybasic face redundant while lipid-binding C2C crucial. These results synergistically through membrane interactions reveal new mechanistic differences between

Язык: Английский

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Regulation of Endosomal Trafficking by Rab7 and Its Effectors in Neurons: Clues from Charcot–Marie–Tooth 2B Disease

Biomolecules, Год журнала: 2023, Номер 13(9), С. 1399 - 1399

Опубликована: Сен. 16, 2023

Intracellular endosomal trafficking controls the balance between protein degradation and synthesis, i.e., proteostasis, but also many of cellular signaling pathways that emanate from activated growth factor receptors after endocytosis. Endosomal trafficking, sorting, motility are coordinated by activity small GTPases, including Rab proteins, whose function as molecular switches direct at membranes through effector proteins. Rab7 is particularly important in coordination degradative functions pathway. effectors control maturation properties late lysosomal compartments, such recycling, motility, fusion with downstream compartments. The spatiotemporal regulation receptor challenging neurons because their enormous size, distinct intracellular domains unique requirements (dendrites vs. axons), long lifespans postmitotic, differentiated cells. In Charcot–Marie–Tooth 2B disease (CMT2B), familial missense mutations cause alterations GTPase cycling leading to an ulcero-mutilating peripheral neuropathy. prevailing hypothesis account for CMT2B pathologies CMT2B-associated alleles alter endocytic neurotrophin NGF its TrkA and, thereby, disrupt normal trophic nervous system, other Rab7-dependent impacted. Here, using a prototypical cargo, we review physiologic interactions neurons. Since among largest cells body, place particular emphasis on temporal spatial sorting neuronal processes. We further discuss current findings mutant models, impact or balance, how this dysregulation may confer disease.

Язык: Английский

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Tomosyn affects dense core vesicle composition but not exocytosis in mammalian neurons

eLife, Год журнала: 2023, Номер 12

Опубликована: Сен. 11, 2023

Tomosyn is a large, non-canonical SNARE protein proposed to act as an inhibitor of complex formation in the exocytosis secretory vesicles. In brain, tomosyn inhibits fusion synaptic vesicles (SVs), whereas its role neuropeptide-containing dense core (DCVs) unknown. Here, we addressed this question using new mouse model with conditional deletion (Stxbp5) and paralogue tomosyn-2 (Stxbp5l). We monitored DCV at single vesicle resolution tomosyn-deficient primary neurons validated pHluorin-based assay. Surprisingly, loss tomosyns did not affect number events but resulted strong reduction intracellular levels cargos, such neuropeptide Y (NPY) brain-derived neurotrophic factor (BDNF). BDNF were largely restored by re-expression inhibition lysosomal proteolysis. Tomosyn's domain was dispensable for rescue. The size trans-Golgi network DCVs decreased, speed cargo flux through Golgi increased neurons, suggesting biogenesis. Additionally, showed impaired mRNA expression some which also observed Cre-expressing wild-type carrying loxP sites, direct effect Cre recombinase on neuronal transcription. Taken together, our findings argue against inhibitory suggests evolutionary conserved function packaging Golgi.

Язык: Английский

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Rab10 regulates neuropeptide release by maintaining Ca²⁺homeostasis and protein synthesis

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Янв. 2, 2024

Abstract Dense core vesicles (DCVs) transport and release various neuropeptides neurotrophins that control diverse brain functions, but the DCV secretory pathway remains poorly understood. Here, we tested a prediction emerging from invertebrate studies about crucial role of intracellular trafficking GTPase Rab10, by assessing exocytosis at single-cell resolution upon acute Rab10 depletion in mature mouse hippocampal neurons, to circumvent potential confounding effects Rab10’s established neurite outgrowth. We observed significant inhibition Rab10-depleted whereas synaptic vesicle was unaffected. However, rather than direct involvement trafficking, this effect attributed two ER-dependent processes, ER-regulated Ca 2+ dynamics protein synthesis. Gene ontology analysis differentially expressed proteins identified substantial alterations ER/ribosomal proteins, including -pump SERCA2. In addition, ER morphology were altered, levels depleted homeostasis impaired neurons. entry using ionophore still triggered less exocytosis. Instead, leucine supplementation, which enhances synthesis, largely rescued deficiency. conclude is required for neuropeptide maintaining regulating Furthermore, appeared more dependent on (acute) synthesis

Язык: Английский

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Rab10 regulates neuropeptide release by maintaining Ca2+ homeostasis and protein synthesis

eLife, Год журнала: 2024, Номер unknown

Опубликована: Март 19, 2024

Dense core vesicles (DCVs) transport and release various neuropeptides neurotrophins that control diverse brain functions, but the DCV secretory pathway remains poorly understood. Here, we tested a prediction emerging from invertebrate studies about crucial role of intracellular trafficking GTPase Rab10, by assessing exocytosis at single-cell resolution upon acute Rab10 depletion in mature mouse hippocampal neurons, to circumvent potential confounding effects Rab10’s established neurite outgrowth. We observed significant inhibition Rab10-depleted whereas synaptic vesicle was unaffected. However, rather than direct involvement trafficking, this effect attributed two ER-dependent processes, ER-regulated Ca 2+ dynamics protein synthesis. Gene ontology analysis differentially expressed proteins identified substantial alterations ER/ribosomal proteins, including -pump SERCA2. In addition, ER morphology were altered, levels depleted homeostasis impaired neurons. entry using ionophore still triggered less exocytosis. Instead, leucine supplementation, which enhances synthesis, largely rescued deficiency. conclude is required for neuropeptide maintaining regulating Furthermore, appeared more dependent on (acute) synthesis

Язык: Английский

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