A new microscope has allowed researchers to watch molecules move within a cell on a millisecond-by-millisecond time scale for the first time. The novel method, which combines two preëxisting microscopic techniques, opens a window onto cellular processes that had previously been undetectable, unveiling molecular activity within a cell at a much finer level than ever before possible.
“This allows us to look at interactions of molecules, and their mobility,” says Malte Wachsmuth, a cell biophysicist at the European Molecular Biology Laboratory in Heidelberg, Germany, who helped develop the new microscope. Current microscopy techniques can home in on a single spot within a cell, but they can miss vital information when the focus moves from one spot to another. “A typical protein might spend one to two milliseconds in such a spot,” Wachsmuth says. “Molecules are quite mobile, diffusing all around, and it’s a very fast process. A lot can happen in a few tens of milliseconds.”