Bruno Antonny, Christopher (Chris) Burd, Elizabeth Chen, Oliver Daumke (organizer), Pietro De Camilli (organizer), Katja Faelber, Marijn Ford, Vadim Frolov, Adam Frost, Jennifer (Jenny) Hinshaw, Thomas (Tom) Kirchhausen, Michael Kozlov, Martin Lenz, Harry Low, Harvey McMahon, Christien Merrifield, Thomas (Tom) Pollard, Philip J. (Phil) Robinson, Aurélien Roux (organizer), Sandra (Sandy) Schmid
by Aurélien Roux, Pietro De Camilli and Oliver Daumke
24 – 29 August, 2015
The living cells are separated from their environment by a lipid membrane that is impermeable to most molecules and ions in solution. Nevertheless, the cell life depends on the exchanges they perform with their environment. These exchanges are carried out in part by a process known as endocytosis, in which the membrane invaginates inward the cell into a spherical bud in order to internalize specific elements of the extracellular medium into a small spherical vesicle.
Oliver Daumke, the Max Delbruck Institute in Berlin, Pietro Camilli, the University of Yale and Aurélien Roux, of the University of Geneva, have gathered in the foundation of Treilles a group of twenty international experts to discuss the latest discoveries and future research on a protein with unique properties, dynamin. This protein is involved in the last step for the internalization of lipid membrane buds. This stage is called fission, and corresponds to the breakage of the neck connecting the bud to the rest of the membrane. Dynamin is a protein capable of winding itself into a helical collar around the neck of endocytic buds. After the discovery of this property, and the fact that inhibition of dynamin prevented the full internalization of buds, scientists have speculated that the function of dynamin is to break the membrane neck bud to release a vesicle. The proposed mechanism was then that the dynamin helix could constrict, compressing the membrane neck until it breaks.
Thus, dynamin was the first clearly identifiable proteinmperforming membrane fission, and its structure immediately suggested a mechanism of action. The function of dynamin is essential to cell life, but also to many other physiological functions. In particular, the formation of synaptic vesicles that allow the transmission of nerve impulses from one neuron to another is strictly dependent on dynamin. But after 25 years of research on dynamin, and although some aspects of the constriction hypothesis have been verified experimentally, it appeared necessary to review the most recent findings, and discuss with experts in the field the different hypotheses proposed to explain the mechanism of dynamin action.
The purpose of this meeting was therefore to discuss the different assumptions, especially that of the constriction, and to establish a consensus on some experimental facts that the cell biology community, represented by experts on dynamin, may consider therefore granted. The conclusions of this discussion will be published in a international scientific journal. A link to the article will be given when available.