Flavivirus membrane fusion.

Flavivirus membrane fusion is mediated by a class II viral fusion protein, the major envelope protein E, and the fusion process is extremely fast and efficient. Understanding of the underlying mechanisms has been advanced significantly by the determination of E protein structures in their pre- and post-fusion conformations and by the elucidation of the quarternary organization of E proteins in the viral envelope. In this review, these structural data are discussed in the context of functional and biochemical analyses of the flavivirus fusion mechanism and its characteristics are compared with those of other class II- and class I-driven fusion processes.