Evidence for a novel affinity mechanism of motor-assisted transport along microtubules

Citation
Y. Wada et al., Evidence for a novel affinity mechanism of motor-assisted transport along microtubules, MOL BIOL CE, 11(1), 2000, pp. 161-169
Citations number
26
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cell & Developmental Biology
Journal title
MOLECULAR BIOLOGY OF THE CELL
ISSN journal
1059-1524 → ACNP
Volume
11
Issue
1
Year of publication
2000
Pages
161 - 169
Database
ISI
SICI code
1059-1524(200001)11:1<161:EFANAM>2.0.ZU;2-T
Abstract
In microtubule (MT) translocation assays, using colloidal gold particles co upled to monoclonal tubulin antibodies to mark positions along MTs, we foun d that relative motion is possible between the gold particle and an MT, gli ding on dynein or kinesin. Such motion evidently occurred by an affinity re lease and rebinding mechanism that did not require motor activity on the pa rticle. As the MTs moved, particles drifted to the trailing edge of the MT and then were released. Sometimes the particles transferred from one MT to another, moving orthogonally. Although motion of the particles was uniforml y rearward, movement was toward the (-) or (+) end of the MT, depending on whether dynein or kinesin, respectively, was used in the assay. These resul ts open possibilities for physiological mechanisms of organelle and other m ovement that, although dependent on motor-driven microtubule transport, do not require direct motor attachment between the organelle and the microtubu le. Our observations on the direction of particle drift and time of release may also provide confirmation in a dynamic system for the conclusion that beta tubulin is exposed at the (+) end of the MT.