Bacteria are single-cell organisms that reproduce by dividing in half. Proteins within these cells organize themselves in a number of fascinating ways during this process, including a recently discovered mechanism that makes the mesmerizing pattern of waves, or oscillations, you see in this video. Produced when the protein MinE chases the protein MinD from one end of the cell to the other, such oscillations are thought to center the cell’s division machinery so that its two new “daughter cells” will be the same size.
To study these dynamic patterns in greater detail, Anthony Vecchiarelli purified MinD and MinE proteins from the bacterium Escherichia coli. Vecchiarelli, who at the time was a postdoc in Kiyoshi Mizuuchi’s intramural lab at NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), labeled the proteins with fluorescent markers and placed them on a synthetic membrane, where their movements were then visualized by total internal reflection fluorescence microscopy. The proteins self-organized and generated dynamic spirals of waves: MinD (blue, left); MinE (red, right); and both MinD and MinE (purple, center) .
The scientists at the IU School of Medicine-Bloomington nicknamed their new microscope the “OMG” for good reason—the images it produces are showstoppers. The DeltaVision OMX imaging system (its official title) is a $1.2 million dollar microscope that can peek inside a cell and image fluorescent proteins in unprecedented detail.
Jane Stout, a researcher in the NIH-funded lab, used the OMG to create this spectacular image that won her first place in the high- and super-resolution microscopy category of the 2012 GE Healthcare Life Sciences Cell Imaging Competition.
What you’re looking at is a cell in the midst of dividing into two identical copies—a process called mitosis. Here, the chromosomes (in blue) are aligned at the cell’s equator. Microtubules (red) from opposite poles of the cell attach to the chromosomes using the kinetochores (green) and pull them to opposite ends of the cell, which then splits in half. But sometimes cells do not divide properly—a common problem in cancer. Understanding the mechanics of cell division could help us correct this process when it goes wrong.
Jane Stout’s prize: her mitosis image will light up a billboard in Times Square in New York City in April. That is a wonderful celebration of science!
NIH support: the National Institute of General Medical Sciences