SEC-uring membrane fusion: a sneak peek at SNARE-complex assembly driven by Sec1-Munc18 proteins

Abstract

Membrane fusion is a fundamentally important process that supports delivery of cellular cargo in systems as diverse as neurotransmission, blood glucose control and mast-cell degranulation. The 2013 Nobel Prize in Physiology or Medicine, awarded to Rothman, Schekman and Südhof1, celebrated their discoveries of the essential membrane-fusion machinery, comprising the SNARE and the Sec1–Munc18 (SM) protein families (Fig. 1). Cognate SNARE partners act as molecular zippers that bring apposing membranes together, but the precise molecular role of the SM proteins has proven much more elusive. A recent article by Baker et al. in Science2 provides new insights into how this vital component operates.