Scientists at Ben-Gurion University of the Negev and researchers from George August University of Göttingen, Germany, have discovered that motor proteins necessary for cells to divide have the ability to move forwards and backwards. This surprising new feature could aid cancer research and nanotechnology.
The scientists reported that these “nano-engines” can, just like man-made automobiles, drastically modify their velocity and even switch their directionality when loaded with a cargo.
The results of the study were recently published online in the EMBO Journal and will be published in the next issue of the European scientific magazine on December 14.
During regular cell division, duplicated chromosomes of the mother cell are distributed into two daughter cells. This tightly regulated process is driven by specialized enzymes, so-called motor proteins, prominent among, which are the families of kinesins and dyneins. Until now it was believed that each member of those families is structurally programmed for a defined directionality on its track, the microtubules of the cytoskeleton. One class of motors generates motion towards the cell poles and another towards the cell equator.
The BGU group, led by Dr. Leah (Larisa) Gheber from the Clinical Biochemistry and Chemistry Departments and the Ilse Katz Institute for Nanoscale Science and Technology, and that of her colleague Prof. Christoph Schmidt from Germany showed that one type of cell division motor in yeast cells can move in both directions. Moreover, the motor protein can move towards the cell poles 10 times faster than all other known motors of the same family.
The scientists reported that a particularly interesting aspect of their findings is that the bi-directional motors switch exactly into the slow forward gear when they bind between two microtubule tracks in the middle of the cell where they help to push the chromosomes apart.
The researchers used high-resolution fluorescence microscopy by which single molecules can be tracked, both in model systems and in living cells.