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Differential regulation of dynein and kinesin motor proteins by tau.

ABSTRACT: Dynein and kinesin motor proteins transport cellular cargoes toward opposite ends of microtubule tracks. In neurons, microtubules are abundantly decorated with microtubule-associated proteins (MAPs) such as tau. Motor proteins thus encounter MAPs frequently along their path. To determine the effects of tau on dynein and kinesin motility, we conducted single-molecule studies of motor proteins moving along tau-decorated microtubules. Dynein tended to reverse direction, whereas kinesin tended to detach at patches of bound tau. Kinesin was inhibited at about a tenth of the tau concentration that inhibited dynein, and the microtubule-binding domain of tau was sufficient to inhibit motor activity. The differential modulation of dynein and kinesin motility suggests that MAPs can spatially regulate the balance of microtubule-dependent axonal transport.

SUBMITTER: Dixit R

PROVIDER: S-EPMC2866193 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature

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Differential regulation of dynein and kinesin motor proteins by tau.

Dixit Ram R Ross Jennifer L JL Goldman Yale E YE Holzbaur Erika L F EL

Science (New York, N.Y.) 20080117 5866

Dynein and kinesin motor proteins transport cellular cargoes toward opposite ends of microtubule tracks. In neurons, microtubules are abundantly decorated with microtubule-associated proteins (MAPs) such as tau. Motor proteins thus encounter MAPs frequently along their path. To determine the effects of tau on dynein and kinesin motility, we conducted single-molecule studies of motor proteins moving along tau-decorated microtubules. Dynein tended to reverse direction, whereas kinesin tended to de ...[more]

PMID: 18202255

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