Retrograde transport by the microtubule-associated protein MAP 1C.
Microtubules are involved in several forms of intracellular motility, including mitosis and organelle movement. Fast axonal transport is a highly ordered form of organelle motility that operates in both the anterograde (outwards from the cell body) and retrograde (from the periphery towards the cell body) direction. Similar microtubule-associated movement is observed in non-neuronal cells, and might be involved in secretion, endocytosis and the positioning of organelles within the cell. Kinesin is a mechanochemical protein that produces force along microtubules in an anterograde direction. We recently found that the brain microtubule-associated protein MAP 1C (ref. 7) is a microtubule-activated ATPase and, like kinesin, can translocate microtubules in an in vitro assay for microtubule-associated motility. MAP 1C seemed to be related to the ciliary and flagellar ATPase, dynein, which is thought to produce force in a direction opposite to that observed for kinesin. Here we report that MAP 1C, in fact, acts in a direction opposite to kinesin, and has the properties of a retrograde translocator.
Paschal
B M
BM
Cell Biology Group, Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts 01545.
Vallee
R B
RB
D000818:Animals; D001692:Biological Transport; D001921:Brain / Q000378:metabolism; D002417:Cattle; D002696:Chlamydomonas / Q000378:metabolism / Q000648:ultrastructure; D005407:Flagella / Q000648:ultrastructure; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure*
D008869:Microtubule-Associated Proteins