Researchers at the Georgia Institute of Technology and Peking University have found a new use for the ubiquitous PowerPoint slide: Producing self-folding three-dimensional origami structures from photocurable liquid polymers.
The cell plasma membrane serves not only as a protective barrier but as the first responder to a changing environment. One environmental challenge these cells face is osmotic stress — where an imbalance of, for instance, ions or sugars, across the plasma membrane exerts osmotic pressure on the membrane. In order to deal with osmotic stress, mammalian cells have evolved complex protein machineries. But how do simpler cells respond to an osmotic onslaught? We answer this question by studying cell-sized lipid vesicles in osmotic stress. Surprisingly, they display a pulsatile behavior, swelling, bursting, and resealing their membrane cycle after cycle.