Scientists Discover a Molecular Motor Has a “Gear” for Directional Switching

Credit; Oregon State University / Weihong Qiu

In this study, researchers focused on a particular motor protein, called KlpA, and used a high-sensitivity light microscopy method to directly follow the movement of individual KlpA molecules on the cytoskeleton track. They discovered that KlpA is able to move in opposite directions – an unusual finding. KlpA-like motor proteins are thought to be exclusively one-way vehicles.

The researchers also discovered that KlpA contains a gear-like component that enables it to switch direction of movement. This allows it to localize to different regions inside the cell so it can help ensure that chromosomes are properly divided for normal cell division.

“In the past, KlpA-like motor proteins were thought to be largely redundant, and as a result they haven’t been studied very much,” Qiu said.

“It’s becoming clear that KlpA-like motors in humans are crucial to cancer cell proliferation and survival. Our results help better understand other KlpA-like motor proteins including the ones from humans, which could eventually lead to novel approaches to cancer treatment.”

Qiu and colleagues say they are excited about their future research, which may uncover the design principle at the atomic level that allows KlpA to move in opposite directions. And there may be other applications.

“KlpA is a fascinating motor protein because it is the first of its kind to demonstrate bidirectional movement,” Qiu said. “It provides a golden opportunity for us to learn from Mother Nature the rules that we can use to design motor protein-based transport devices. Hopefully in the near future, we could engineer motor protein-based robotics for drug delivery in a more precise and controllable manner.”

The work was done with partial support from the National Science Foundation.

Contacts and sources:
David Stauth,
Oregon State University