Conformational spread: the propagation of allosteric states in large multiprotein complexes.
The phenomenon of allostery is conventionally described for small symmetrical oligomeric proteins such as hemoglobin. Here we review experimental evidence from a variety of systems-including bacterial chemotaxis receptors, muscle ryanodine receptors, and actin filaments-showing that conformational changes can also propagate through extended lattices of protein molecules. We explore the statistical mechanics of idealized linear and two-dimensional arrays of allosteric proteins and show that, as in the analogous Ising models, arrays of closely packed units can show large-scale integrated behavior. We also discuss proteins that undergo conformational changes driven by the hydrolysis of ATP and give examples in which these changes propagate through linear chains of molecules. We suggest that conformational spread could provide the basis of a solid-state "circuitry" in a living cell, able to integrate biochemical and biophysical events over hundreds of protein molecules.
Bray
Dennis
D
Department of Zoology, University of Cambridge, Cambridge CB2 3EJ, United Kingdom. db10009@cam.ac.uk
Duke
Thomas
T
D000494:Allosteric Regulation / Q000502:physiology; D000495:Allosteric Site; D019281:Dimerization; D046911:Macromolecular Substances; D008954:Models, Biological; D008956:Models, Chemical; D008958:Models, Molecular; D020409:Molecular Motor Proteins / Q000737:chemistry* / Q000502:physiology; D011485:Protein Binding; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
D046911:Macromolecular Substances; D020409:Molecular Motor Proteins; D011506:Proteins