Thanks to a new microscope, scientists can now take 3-D movies of molecular processes that previously were invisible to us. Developed at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, the microscope allows researchers to peer into living cells and see multiple molecules in action. It is already providing new insights into the biochemistry of life.
How it Works
Like many technological advances, the new microscope combines previous techniques to take a significant leap forward. Light-sheet microscopy is a common research technique that illuminates a microscopic object with a sheet of light. The microscope then takes snapshots of the object from multiple angles to produce a 3-D image. Another technique, single molecule spectroscopy, has allowed scientists to tag a molecule with fluorescence and then use the fluorescence to observe the molecule, though not much else.
Greater than the Sum of Its Parts
The new microscope combines light-sheet microscopy with single molecule spectroscopy. It allows researchers to observe and measure the complex processes of living cells molecules, which are so small they are measured in nanometers (to give you an idea of how small a nanometer is, if you are five feet, eight inches tall then you are also about 1,727,200,000 nanometers tall, close to two billion!).
Pixel by Pixel Views
Unlike single molecule spectroscopy, the new microscope can record every pixel in view across a sample, even if the sample contains multiple cells. The microscope can also take shots at intervals less than a millisecond, allowing it to record the processes it is observing as movies in 3-D. You can see some of the new microscope movies of subjects such as yeast cells and fruit fly larval wings at http://www.nature.com/nbt/journal/vaop/ncurrent/abs/nbt.1928.html
The microscope can only be used in living cells, but in doing so, it will allow scientists to better understand a variety of biochemical processes (everything your body is doing right now, including reading this screen, is a result, at least partially, of biochemical processes). It has already provided surprises to scientists who study chromatin, which is basically the DNA, RNA and protein that make up the chromosomes in a cell’s nucleus.
Scientists had previously only observed chromatin either tightly wound and therefore unreadable to the cell, like a closed book, or loose and readable, like an open book. The new microscope has revealed that in the presence of a certain protein, chromatin appears to have an intermediate stage between the previously known stages.
This is only the beginning. Because the microscope can observe complex processes in what is almost real time, scientists predict it will help us better understand a variety of biochemical processes, ranging from the role of growth hormones in cancer to the regulation of cell division and the patterning of tissue development in an embryo.