Like the iris in a camera lens that controls light, the lid of this barrel-shaped molecule opens and closes to control how proteins fold into the unique shapes that determine their function. The exact manner by which proteins fold has been a mystery. Scientists knew that some proteins fold inside these molecules, called chaperonins, but they couldn't see how. This movie of the chaperonin TRiC literally unlocks the door, showing that the opening's widening and narrowing dictates how proteins fold or unfold. The advance also offers new details on how a protein lines up inside the chaperonin and folds once the door closes. Courtesy of molecular biologist Judith Frydman, Stanford University.
This work also was supported by the NIH Roadmap for Medical Research.