Using new technology developed in his University of Oregon lab, chemist Andrew H. Marcus and his doctoral student, Eric N. Senning, have captured what they describe as well-orchestrated, actin-driven, mitochondrial movement within a single cell. That movement appears to be coordinated by mitochondria's recruitment of actin-related proteins that rapidly assemble into extended fractal-like structures in a molecular chemical reaction known as polymerization. The coordinated movement of mitochondria is important for reproduction of identical daughter cells, and the sorting of mitochondrial DNA into the spinoff cells.

The research was done with a molecular fluorescence technology called Fourier imaging correlation spectroscopy that allows researchers using focused laser beams to see, measure, and map the intermittent movement of mitochondria at micron scales. In their project, Senning and Marcus looked at actin's behavior using inhibitory agents to monitor mitochondrial activity in Saccharomyces cerevisiae, a species of budding yeast often used in research. They also introduced two defective forms of the protein. Their technique included the use of hormones to trick a yeast cell into thinking it was about to mate, so that it stops dividing and sits and fluctuates. From this state, the images are drawn.

The picture that emerged, Marcus said, was that actin is drawn to the surfaces of mitochondria to regulate the polymerization machinery so that it operates in an efficient, organized manner. The findings lend support to an existing model in which non-equilibrium forces are directly coupled to mitochondrial membrane surfaces.