Like many machines, cells have motors that help them carry out essential tasks. In the case of divisiona process that goes horribly awry in cancer cellsa protein motor known as dynein plays a critical role. Indeed, dynein appears to ferry chromosomes and other materials to the appropriate locations within a cell before it splits in two. To get a better understanding of this motor, Ohio University researcher Elisar Barbar and her colleagues recently studied a few of its 12 components, which they described yesterday at the annual meeting of the Biophysical Society in Boston.

The scientists found that in order to function properly, dynein's components must have a certain form and must fit together in a particular way. Problems with even a single component, it turns out, can have disastrous effects. In studies of fruit flies, Barbar's team found that mutations in one of the dynein pieces, called LC8, can cause sterility, neural defects and even death. The team also examined where dynein's pieces link together and how the protein latches on to its cargo.

Much more work is needed before scientists fully understand how dynein operates. But when they do, they may then be able to disarm the protein to halt cancerous growths. If researchers can prevent dynein from transporting chromosomes, team member Michael Hare explains, cells won't divide. In fact, the anticancer drug Taxol is based on a related approach: it destroys the pathways on which the dynein motor travels. "You can either pull up the train tracks or destroy the engine," Hare observes. "It will have the same effect."