Jean-Pierre Changeux
Jean-Pierre Changeux is professor at the Collège de France, and at the Institut Pasteur, where he has directed, since 1967, a laboratory of Molecular Neurobiology. His main contributions and discoveries in the course of the past 37 years are centered on the general theme of the molecular and cellular mechanisms of signal recognition and transduction, also referred to as receptor mechanisms, primarily in the nervous system.
In his early work, as a student of Jacques Monod, Changeux made essential discoveries with the bacterial enzyme L-threonine deaminase on the experimental basis and theoretical foundation of allosteric interactions between topographically distinct sites as a general mechanism of signal transduction mediated by specific conformational changes. Subsequently, Changeux extended these views to the receptors for neurotransmitters involved in synaptic transmission. Together with his group, he made the decisive steps in the identification of the acetylcholine nicotinic receptor, the first neurotransmitter receptor linked to a ion channel, and unravelled the main features of its functional organization (in particular its active site and ion channel) as well as the mechanisms of its activation and short-term regulation, in particular by desensitization, thus substantiating its properties as "allosteric membrane protein".
Furthermore, Changeux and his collaborators have proposed a model of epigenesis of neural networks by selective stabilization of synapses, and analyzed in these terms the molecular mechanisms involved in the regulation of acetylcholine receptor genes expression during the development of the motor endplate. These issues are of relevance for the understanding of long term synaptic plasticity.
In the field of cognition, Changeux original extension of the selectionist scheme to the epigenesis of neuronal networks and to higher brain functions has inspired a number of theoreticians and experimentalists. In this respect, his book L'homme neuronal, 1983, Librarie Arthème Fayard, was widely acclaimed by scientist from very different disciplines.
His seminal work on the nicotinic receptor has pioneered new fields of research in signal transduction mechanisms, molecular pharmacology and pathology of chemical communications in the nervous system.
The title of his contribution to the Cajal Conference is From Molecular Biology to Cognitive Function: The Nicotinic Receptor.
