The two motor domains of KIF3A/B coordinate for processive motility and move at different speeds.

ABSTRACT: KIF3A/B, a kinesin involved in intraflagellar transport and Golgi trafficking, is distinctive because it contains two nonidentical motor domains. Our hypothesis is that the two heads have distinct functional properties, which are tuned to maximize the performance of the wild-type heterodimer. To test this, we investigated the motility of wild-type KIF3A/B heterodimer and chimaeric KIF3A/A and KIF3B/B homodimers made by splicing the head of one subunit to the rod and tail of the other. The first result is that KIF3A/B is processive, consistent with its transport function in cells. Secondly, the KIF3B/B homodimer moves at twice the speed of the wild-type motor but has reduced processivity, suggesting a trade-off between speed and processivity. Third, the KIF3A/A homodimer moves fivefold slow

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC1304584 | biostudies-literature | 2004 Sep

REPOSITORIES: biostudies-literature