Bioengineering’s Diehl investigates biomotor mechanics

Bioengineering’s Diehl investigates biomotor mechanics

BY JADE BOYD
Rice News staff
 
In his search for an analogy to describe his research, bioengineering’s newest faculty member, Michael Diehl, hits upon the idea of long-distance running.

His research involves the study of motor proteins that run from place to place, carrying biomolecular cargo and other chemical commodities that are essential to maintaining healthy cellular function. In cells, these motors travel while taking nanometer-scale steps along ”trails” called microtubules. However, compared to a long-distance runner, these motors operate in the presence of thermal and chemical fluctuations.

”It’s really a chaotic environment, so the overall affect is something like trying to run a 10K through a magnitude 10 earthquake,” said Diehl, assistant professor of bioengineering.

Diehl arrived at Rice three months ago from Caltech, where he has served as a Beckman Senior Research Fellow since 2002. His research at Rice is centered on understanding how the mechanics of such motors are regulated in cells so that the right cargo is transported to the right place and at the right time.

His first attempt to investigate collective biomotor mechanics was carried out in collaboration with Professor David Tirrell at Caltech and published in the March 10 issue of Science.

”There are a variety of mechanisms available to nature that provide control over the mechanics of motor proteins, and it is becoming more and more apparent that many of these mechanisms are derived from the ability of several motors to work together in an orchestrated fashion,” Diehl said.

The notion of motors working together brings an interesting perspective to the marathon analogy. ”Now imagine running this race while you are tied to your neighboring runners,” he said.

Diehl’s research group studies interacting assemblies of motor proteins. They build ”chain-gangs” of motors by connecting them to modular synthetic polymers, and they watch these assemblies move using sensitive optical microscopes. Their synthetic techniques provide precise control over the number of motors and how they are connected together.

”Consequently, we have intimate knowledge of the molecular architecture of these assembles and can control parameters such as the elasticity of motor-motor connections,” he said.

Diehl said his approach has some important advantages over other experimental methods.

”In cells, such details are difficult to determine, much less control,” he said.

Diehl said he became fascinated with the power of biological systems when he realized there were parallels to his research in designing nanotech circuitry in graduate school. Diehl earned his doctorate at the University of California at Los Angeles under the tutelage of Jim Heath, Rick Smalley’s most-recognized former student.

”In Jim’s lab I was using molecular materials to build integrated circuits and that is so much of what biology is,” Diehl said.