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18 papers found.
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Myelination at a glance

The myelin sheath is a plasma membrane extension that is laid down in regularly spaced segments along axons of the nervous system. This process involves extensive changes in oligodendrocyte cell shape and membrane architecture. In this Cell Science at a Glance article and accompanying poster, we provide a model of how myelin of the central nervous system is wrapped around axons...

Subcortical cytoskeleton periodicity throughout the nervous system

Medicine, Hermann-Rein-Straße 3, 37075 Göttingen, GermanyCaroline Velte & Mikael Simons AuthorsSearch for Elisa D’Este in:Nature Research journals • PubMed • Google ScholarSearch for Dirk Kamin in:Nature ... ScholarSearch for Mikael Simons in:Nature Research journals • PubMed • Google ScholarSearch for Stefan W. Hell in:Nature Research journals • PubMed • Google Scholar Contributions E.D., D.K. and C.V. performed

Exosomes: vesicular carriers for intercellular communication in neurodegenerative disorders

The intercellular transfer of misfolded proteins has received increasing attention in various neurodegenerative diseases characterized by the aggregation of specific proteins, as observed in Alzheimer’s, Parkinson’s and Huntington’s disease. One hypothesis holds that intercellular dissemination of these aggregates within the central nervous system results in the seeded assembly...

Dynamics of the Peripheral Membrane Protein P2 from Human Myelin Measured by Neutron Scattering—A Comparison between Wild-Type Protein and a Hinge Mutant

Myelin protein P2 is a fatty acid-binding structural component of the myelin sheath in the peripheral nervous system, and its function is related to its membrane binding capacity. Here, the link between P2 protein dynamics and structure and function was studied using elastic incoherent neutron scattering (EINS). The P38G mutation, at the hinge between the β barrel and the...

Cell Visco-Elasticity Measured with AFM and Optical Trapping at Sub-Micrometer Deformations

The measurement of the elastic properties of cells is widely used as an indicator for cellular changes during differentiation, upon drug treatment, or resulting from the interaction with the supporting matrix. Elasticity is routinely quantified by indenting the cell with a probe of an AFM while applying nano-Newton forces. Because the resulting deformations are in the micrometer...

Actomyosin contractility controls cell surface area of oligodendrocytes

Background To form myelin oligodendrocytes expand and wrap their plasma membrane multiple times around an axon. How is this expansion controlled? Results Here we show that cell surface area depends on actomyosin contractility and is regulated by physical properties of the supporting matrix. Moreover, we find that chondroitin sulfate proteoglycans (CSPG), molecules associated with...

A Global In Vivo Drosophila RNAi Screen Identifies a Key Role of Ceramide Phosphoethanolamine for Glial Ensheathment of Axons

Glia are of vital importance for all complex nervous system. One of the many functions of glia is to insulate and provide trophic and metabolic support to axons. Here, using glial-specific RNAi knockdown in Drosophila, we silenced 6930 conserved genes in adult flies to identify essential genes and pathways. Among our screening hits, metabolic processes were highly represented...

Targeted Ablation of Oligodendrocytes Triggers Axonal Damage

Glial dysfunction has been implicated in a number of neurodegenerative diseases. In this study we investigated the consequences of glial and oligodendrocyte ablation on neuronal integrity and survival in Drosophila and adult mice, respectively. Targeted genetic ablation of glia was achieved in the adult Drosophila nervous system using the GAL80-GAL4 system. In mice...

Myelin Membrane Assembly Is Driven by a Phase Transition of Myelin Basic Proteins Into a Cohesive Protein Meshwork

Myelin basic protein undergoes a phase transition from a cytoplasmic soluble pool into a cohesive functional amyloid-like assembly; this may be one mechanism of myelin membrane biogenesis.

Large-Scale Screen for Modifiers of Ataxin-3-Derived Polyglutamine-Induced Toxicity in Drosophila

Polyglutamine (polyQ) diseases represent a neuropathologically heterogeneous group of disorders. The common theme of these disorders is an elongated polyQ tract in otherwise unrelated proteins. So far, only symptomatic treatment can be applied to patients suffering from polyQ diseases. Despite extensive research, the molecular mechanisms underlying polyQ-induced toxicity are...

Identification of Tmem10/Opalin as a novel marker for oligodendrocytes using gene expression profiling

Background During the development of the central nervous system, oligodendrocytes generate large amounts of myelin, a multilayered insulating membrane that ensheathes axons, thereby allowing the fast conduction of the action potential and maintaining axonal integrity. Differentiation of oligodendrocytes to myelin-forming cells requires the downregulation of RhoA GTPase activity...

Neurotransmitter-Triggered Transfer of Exosomes Mediates Oligodendrocyte–Neuron Communication

Neuronal activity provokes myelinating oligodendrocytes to release exosomes by stimulation of ionotropic glutamate receptors, and that once released, these vesicles are internalized by neurons conveying neuroprotection.

Extracellular vesicle sorting of α-Synuclein is regulated by sumoylation

Extracellular α-Synuclein has been implicated in interneuronal propagation of disease pathology in Parkinson’s Disease. How α-Synuclein is released into the extracellular space is still unclear. Here, we show that α-Synuclein is present in extracellular vesicles in the central nervous system. We find that sorting of α-Synuclein in extracellular vesicles is regulated by...