Molecular motion in detail
In a critical breakthrough in unraveling how molecular “motors” ferry proteins and nutrients through cells, Harvard scientists have produced high-resolution images that show how the “foot” of dynein — one of the most complex, but least understood such motors — binds to microtubules, the cellular tracks it travels on. As described in a Sept. 20 paper in Science, a team of researchers, led by Andres Leschziner, associate professor of molecular and cellular biology at Harvard Medical School (HMS), and Samara Reck-Peterson, HMS assistant professor of cell biology, showed that dynein’s foot dramatically changes shape as it binds to the microtubule. Those chemical changes, Leschziner said, suggest that the foot acts as a sensor to aid coordinated movement. “In some ways, the idea that dynein is binding to the microtubule is not especially interesting,” Leschziner said. “What is truly exciting about this research is the finding that, because the foot changes shape as...