Neurons cytoskeleton

A dynamic neuronal cytoskeleton provides for specialized functions in different regions of the neuron 131... 

The neuronal cytoskeleton plays a number of roles, such as providing structural support and transporting organelles however, the idea that it is a transduction site is relatively recent (Quinlan Halpain, 1996 Sanchez et al., 1999 Woolf, 1999a). The MAP-2 molecule may play a primary role in this regard because it binds not only to the microtubular matrix, but also to micro-... 

The neuronal cytoskeleton provides the axon with mechanical support and is directly involved in the transport of materials from the cell body towards the synapse (anterograde transport) and in the opposite direction (retrograde transport). Axons are generally covered (insulated) with a myelin sheath, which is formed by oligodendrocytes (in the CNS) or Schwann cells (PNS). 

Another proposed mechanism underlying MeHg toxicity is dismption of microtubules in the neuronal cytoskeleton (Mima and Imma 1987). Hg binds to thiols in the tubulin, the protein monomers that form micro... 

IDPN. Colourless liquid, bp 134°C. Absorbed by oral, inhalation and dermal routes but relatively high doses (of the order of g/kg bw) required for toxic effects. Produces waltzing syndrome in rodents. Damages axons in spinal cord and brain stem by interaction with neuronal cytoskeleton. 

The postsynaptic response to a chemical messenger appears to occur at postsynaptic active zones, which can be recognized morphologically at sites where nerve terminals make contact with other neurons or effector cells such as striated muscle. They consist of a pronounced density of intra-membranous particles as viewed under electron microscopy. These particles are at least 100-fold more enriched in active zones when compared to the remainder of the membrane. At the cholinergic nerve-muscle junction, evidence exists to suggest that these intramembranous particles are in fact ion channel—receptor complexes. Portions of the particles, thought to be the receptors, turn over with a time course of days, but the overall integrity of the active zones remains intact. In the cerebral cortex of the central nervous system, dendritic spines of neurons have been shown to be concentrated with active zones. These active zones appear to be intimately associated with portions of the neuronal cytoskeleton, since the cytoplasmic portion of the active zone displays a prominent band of fuzzy material, which, in turn, makes contact with microfilaments. 

Different fluorescence microscopy techniques are commonly used to explore the organization of the microtubule cytoskeleton. The resolution of these techniques is, however, limited by diffraction to approximately 250 nm, which makes them not suitable for nanoscale mapping of microtubule properties. Superresolution microscopy techniques that rely on single molecule localization (Single Molecule Localization Microscopy SMLM) combine high protein specificity, multi-color imaging, and a resolution in the order of 5-50 nm, making it an ideal tool to study the neuronal cytoskeleton and its properties. 

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