Axonal transport kinesins

MTs extend from the centrosome throughout the cytoplasm to the plasma membrane, where they are stabilized by caps. Sliding along the MTs, kinesin and dynein motors transport their cargoes between the center and the periphery of the cell. MTs present in the axons of neur ons are extended not only by addition of heterodimers to the plus ends but also by use of short MTs that initiate in the centrosome. Their axonal transport is mediated by dynein motors that are passively moved along actin filaments. Once formed in the axon, MTs serve as tracks for the fast axonal transport, i.e. the movement of membranous organelles and membrane proteins to the nerve ending. 

In neurons and non-neuronal cells, kinesin is associated with a variety of MBOs, ranging from synaptic vesicles to mitochondria to lysosomes. In addition to its role in fast axonal transport and related phenomena in non-neuronal cells, kinesin appears to be involved in constitutive cycling of membranes between the Golgi and endoplasmic reticulum. However, kinesin is not associated with all cellular membranes. For example, the nucleus, membranes of the Golgi complex and the plasma membrane all appear to lack kinesin. Kinesin interactions with membranes are thought to involve the light chains and carboxyl termini of heavy chains. However, neither this selectivity nor the molecular basis for binding of kinesin and other motors to membranes is well understood. 

Elluru, R., Bloom, G. S. and Brady, S. T. Fast axonal transport of kinesin in the rat visual system functionality of the kinesin heavy chain isoforms. Mol. Biol. Cell 6 21-40,1995. 

The axonal transport of APP in neurons is mediated by the direct binding of APP to the kinesin light chain subunit of kinesin I. An axonal membrane compartment contains APP, P-secretase, and PSl, and the fast anterograde axonal transport of this compartment is mediated by APP and kinesin I. APP proteolysis in this... 

Kamal, A., Almenar-Queralt, A., LeBlanc, J.F., Roberts, E.A., Goldstein, L.S.B. (2001) Kinesin-mediated axonal transport of a membrane compartment containing beta-secretase and presenilin-1 requires APP. Nature, 414, 643-648. 

Lazarov O, Morfini GA, Lee EB, Farah MH, Szodorai A, DeBoer SR, Koliatsos VE, Kins S, Lee VM, Wong PC, Price DL, Brady ST, Sisodia SS (2005) Axonal transport, amyloid precursor protein, kinesin-1, and the processing apparatus revisited. J Neurosci 25(9) 2386-2395 Lee AC, Harris JP (1999) Problems with the perception of space in Parkinson s disease. Neuroophthalmology 22 1-15... 

Kinesin participates in vesicle transport in a number of cell types, including fast axonal transport in neurons (56). In Sertoli cells, kinesin has been observed to localize to the trans Golgi network, a location suggesting involvement in membrane trafficking within the cell (57). In addition, kinesin is localized to ectoplasmic specializations where it may be involved in the movement and positioning of elongate spermatids within the seminiferous epithelium (55). 

Hall DH, Hedgecock EM. 1991. Kinesin-related gene unc-104 is required for axonal transport of synaptic vesicles in C. elegans. Cell 65 837M7... 

Kamal, A., Stokin, G.B., Yang, Z., Xia, C.H. and Goldstein, L.S. 2000. Axonal transport of amyloid precursor protein is mediated by direct binding to the kinesin light chain subunit of kinesin-I. Neuron 28 449-459... 

Kanaan, N.M., Morfini, G.A., LaPointe, N.E., et al., 2011. Pathogenic forms of tau inhibit kinesin-dependent axonal transport through a mechanism involving activation of axonal phosphotransferases. J. Neurosci. 31, 9858-9868. 

Figure 6. Transport of material along the nerve axon. Materials such as neurotransmitter peptides are synthesized in the cell body and sequestered in vesicles at the Golgi. Vesicles are then transported down the axon towards the synapse by kinesin motors. Other materials are transported from the synapse to the cell body by dynein motors.

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