Molecular memory of periodic thermal stimulation in an immune complex

Abstract

The mechanisms by which a protein searches its vast conformational space in order to attain its native fold in physiological times and to bind productively to relevant biological partners are not well understood. In particular, most proteins must be able alternate between at least one active conformational state and back to an inactive conformer, especially for the macromolecules that perform work and need to optimize ATP usage. This property may be invoked by a physical stimulus (temperature, radiation) or a chemical ligand. We have stimulated with temperature cycles two partners of an immune complex and revealed that properties of the external stimulus (period, phase) are also found in characteristics of the protein complex (i.e. periodic variation in its binding affinity). These results may be important for delineating in vitro the bases of molecular memory.