Transport, retrograde

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... 

Neuroanatomists have taken advantage of the phenomenon of fast retrograde transport to locate remote nerve cell bodies in the CNS of an experimental animal that are connected to an identified axonal fiber tract whose origin is uncertain. The tracer material [purified horseradish peroxidase (HRP) enzyme] is injected in the region of the axon terminals, where it is taken up by endocytosis and then is carried by retrograde axonal transport over a period of several hours to days back to the nerve cell body. The animal is sacrificed, and the enzyme tracer is localized by staining thin sections of the brain for peroxidase activity. 

There is considerable evidence that a second trans-poson in the ER membrane is involved in retrograde transport of various molecules from the ER lumen to the cytosol. These molecules include unfolded or mis-folded glycoproteins, glycopeptides, and oligosaccharides. Some at least of these molecules are degraded in proteasomes. Thus, there is two-way traffic across the ER membrane. 

Step 8 Retrograde transport occurs to restart the cycle. This last step may retrieve certain proteins or recycle v-SNAREs. Nocodazole, a microtubule-disrupting agent, inhibits this step. 

Mamounas, L.A., and Molliver, M.E. Dual serotonergic projections to forebrain have separate origins in the dorsal and median raphe nuclei Retrograde transport after selective axonal ablation by p-chloroamphetamine (PCA). Abstr Soc Neurosci 13 907, 1987. 

Lidke, D. S., Lidke, K. A., Rieger, B., Jovin, T. M. and Arndt-Jovin, D. J. (2005). Reaching out for signals Filopodia sense EGF and respond by directed retrograde transport of activated receptors. J. Cell Biol. 170, 619-26. 

Amessou, M., Fradagrada, A., Falguieres, T., Lord, J.M., Smith, D.C., Roberts, L.M., Lamaze, C., and Johannes, L. (2007) Syntaxin 16 and syntaxin 5 are required for efficient retrograde transport of several exogenous and endogenous cargo proteins./. Cell Sci. 120, 1457-1468. 

COPI-coated vesicles mediate intra-Golgi transport and Golgi to ER retrograde transport. The coats of these vesicles do not show the geometric forms seen with clathrin coats and have a more complex protein composition [3]. Coat protein purification first lead to the identification of a complex composed of seven individual coat-protein subunits, known as COPI or coatomer. Some of these subunits bear a sequence similarity to clathrin adaptors. In addition, there is a small GTP-binding protein, Arfl, present on COPI-coated vesicles. 

Cole,N.B.,Ellenberg, J.,Song, J.,DiEuliis,D. and Lippincott-Schwartz, J. Retrograde transport of Golgi-localized proteins to the ER. J. Cell Biol. 140 1-15,1998. 

Tsukita, S. and Ishikawa, H. The movement of membranous organelles in axons. Electron microscopic identification of anterogradely and retrogradely transported organelles. /. Cell Biol. 84 513-530,1980. 

Retrograde transport returns trophic factors, exogenous material and old membrane constituents to the cell body 492... 

Kristensson, K. Retrograde transport of macromolecules in axons. Annu. Rev. Pharmacol. Toxicol. 18 97-110,1987. 

Hafezparast, M., Klocke, R., Ruhrberg, C. et al. Mutations in dynein link motor neuron degeneration to defects in retrograde transport. Science 300 808-812, 2003. 

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