Disorder-to-order transition of Synaptobrevin-2: Tracing the conformational diversity of a synaptic SNARE protein

[Display omitted] •Synaptobrevin-2 is unstructured in the absence of interaction partners.•Lipid membranes and SNARE proteins induce helix formation of Synaptobrevin-2.•Membrane binding is mediated by electrostatic interactions.•SNARE complex stability is accomplished by 15 hydrophobic and one ionic layers. Synaptobrevin-2 is one of the key players of neuronal exocytosis. Together with Syntaxin-1A and SNAP25, it forms the core membrane fusion machinery that is responsible for neurotransmitter release and, therefore, signal transmission between neurons. However, in the absence of interaction partners, Synaptobrevin-2 is largely unstructured and exhibits an inherent flexibility. In this graphical review, we provide an overview on the structural states of Synaptobrevin-2 in the absence and in the presence of interaction partners. For this, we first depict its natural habitat, namely the presynaptic nerve terminal, and gather biophysical properties that are likely responsible for its structural diversity. We then provide an overview on key findings describing the disorder-to-order transition of Synaptobrevin-2 from a mostly unstructured protein to a highly structured protein complex component.