Anterograde transport

COPI vesicles mediate anterograde transport from the intermediate compartment to the Golgi, transport within the Golgi apparatus and retrograde transport back from the Golgi to the ER by the recruitment of soluble... 

The differential vulnerability of fine and beaded 5-HT axons, combined with evidence from anterograde transport that fine and beaded fibers arise from the DR and MR nuclei, respectively, led to the proposal that axons from the DR nucleus are selectively vulnerable to the neurotoxic effects of psychotropic amphetamines, while the MR projection is resistant. The prior anterograde transport study (Kosofsky 1985 Kosofsky and Molliver 1987) sampled a relatively small number of neurons in the central portions of the DR and MR nuclei and suggested a predominantly differential origin of the two axon types. In order to determine directly whether the DR and MR projections are differentially sensitive to psychotropic amphetamines,... 

Newly synthesized membrane and secretory proteins destined for the axon travel by fast anterograde transport 488... 

Anterograde transport moves synaptic vesicles, axolemmal precursors and mitochondria down the axon 491... 

Kinesins mediate anterograde transport in a variety of organisms and tissues 495... 

Newly synthesized membrane and secretory proteins destined for the axon travel by fast anterograde transport. However, not all membrane-bounded organelles (MBOs) are destined for the axon. As a result, the first stage of transport must be synthesis, sorting and packaging of organelles (see Ch. 9). Once assembled, the organelle must then be committed to the transport... 

Kinesins mediate anterograde transport in a variety of organisms and tissues. Since its discovery, much has been learned about the biochemical, pharmacological and molecular properties of kinesin [44, 45], Kinesin is the most abundant member of the kinesin family in vertebrates and is widely distributed in neuronal and nonneuronal cells. The holoenzyme is a heterotetramer comprising two heavy chains (115-130 kDa) and two light... 

Cytoplasmic dyneins may have multiple roles in the neuron. The identification of kinesin as a plus-end directed microtubule motor suggested that it is involved in anterograde transport but left the identity of the retrograde motor an open question. Since flagellar dynein was known to be a minus-end-directed motor, interest in cytoplasmic dyneins was renewed. Identification of the cytoplasmic form of dynein in nervous tissue came as an indirect result of the discovery of kinesin. 

The vesicles used in the retrograde transport from the Golgi to the ER are coated by the COP I protein, whereas in the anterograde transport from the ER to the Golgi, the COP II protein seems to be a principal player. The dilysine motif turned out to interact with COP I, directing the retrieval to the ER. This is plausible because COP I exists on the cytosolic surface of the Golgi membrane. 

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). 

ALS SOD-1 unknown Trophic factor GDNF, IGF Global SC Retrograde, anterograde transport, intrathecal, intramuscular Wang et al. (2002b) Kaspar et al. (2003) Foust et al. (2004)... 

Fast anterograde transport can reach rates as high as 400 mm/day. It is dependent upon microtubules that provide a track along which the vesicles move. The movement is energy dependent and is mediated by a specific motor protein, kinesin. A similar process is responsible for fast retrograde transport. A second motor protein, dynein, is needed for movement in that direction. A third type of transport process is termed slow axoplasmic transport. It ranges from 0.2 to 5 mm/day and is responsible for the transport of cytoskeletal proteins, the neurofilaments, and microtubules, as well as an assortment of cytoplasmic proteins. 

Axons transport materials from the cell body to the synaptic terminals (anterograde transport) and in the opposite direction (retrograde transport). Anterograde transport may occur slowly (a few millimeters/ day only) or fast (up to 400 mm/day), whereas retrograde transport is always fast. Diffusion in the perpendicular direction (not along axons) is much more limited as the membranes and the myelin sheath form obstacles. Therefore, diffusion is not isotropic (same in all directions) in the WM. This phenomenon is known as diffusion anisotropy . In contrast, diffusion is rel-... 

Polcicova K. Herpes keratitis in the absence of anterograde transport of virus for sensory gangUa to the cornea. Proc Natl Acad Sci USA 2005 102(32) 11462-11467. 

Meibach RC, Siegel A (1977a) Efferent connecdons of die septal area in die rat An analysis udlizing retrograde and anterograde transport mediods. Brain Res 119 1—20. 

Axon is a polarized extension from cell body, and its plus-end nerve terminal contains presynaptic terminal. The growing axons often contain grow th cones at the nerve terminal, mobility of which is critically important for the axonal plasticity. The axon is packed with cargo moving along a unipolar microtubule array either tov ard the nerve terminal (anterograde transport)... 

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