Cholesterol, regulated exocytosis and the physiological fusion machine.

  title={Cholesterol, regulated exocytosis and the physiological fusion machine.},
  author={Matthew A Churchward and Jens R Coorssen},
  journal={The Biochemical journal},
  volume={423 1},
Exocytosis is a highly conserved and essential process. Although numerous proteins are involved throughout the exocytotic process, the defining membrane fusion step appears to occur through a lipid-dominated mechanism. Here we review and integrate the current literature on protein and lipid roles in exocytosis, with emphasis on the multiple roles of cholesterol in exocytosis and membrane fusion, in an effort to promote a more molecular systems-level view of the as yet poorly understood process… 

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Comment on "Transmembrane Segments of Syntaxin Line the Fusion Pore of Ca2+-Triggered Exocytosis"

A model in which multiple syntaxin transmembrane domains (TMDs) act as subunits of a proteinaceous fusion pore is described, which seems intriguing.