Proteins in Motion

摘要

Three years ago, a special issue of science (14 april 2006) focused on new tools used to observe proteins at work. The view that has emerged is that of an intricate ballet: Individual proteins are in constant motion, sampling an ensemble of different conformations and perhaps changing interaction partners as they play their part in a particular biological process.rnHow do these dynamics affect function? The conformational space that a protein can explore can be described by an energy landscape, in which different conformations are populated based on their energies, and rates of interconversion are dependent on the energy barriers between states. The landscape, and thus the relative populations of conformational states, can be modulated, for example, by interactions with other proteins or by covalent modifications such as phosphorylation. Smock and Gierasch (p. 198) present examples that illustrate how these dynamic properties allow proteins to transmit signals by acting as switches and transducers.