Multisubunit tethers in membrane fusion.

Cells are largely compartmentalized into numerous interacting organelles with dedicated functions in lipid metabolism, energy generation, or protein turnover. In the past, each organelle has been considered as an isolated unit with an individual proteome, membrane composition, and shape. However, this view is changing rapidly as organelles communicate via contact sites, fuse directly with each other, or correspond via vesicular carriers. Each of these processes disturbs the initial individual character of each organelle and they thus need to be tightly controlled and regulated.