Baculovirus GP64 disulfide bonds: the intermolecular disulfide bond of Autographa californica multicapsid nucleopolyhedrovirus GP64 is not essential for membrane fusion and virion budding.

ABSTRACT: The GP64 envelope glycoprotein of the Autographa californica nucleopolyhedrovirus (AcMNPV) is a class III viral membrane fusion protein that is triggered by low pH during entry. Unlike most other viral fusion protein trimers, the monomers of GP64 are covalently linked to each other within the trimer by a single intermolecular disulfide bond (Cys24 Cys372). Single or paired alanine substitutions for Cys24 and Cys372 resulted in lower-efficiency transport of GP64 to the cell surface. Surprisingly, these mutated GP64s induced syncytium formation, and normalized fusion activities were approximately 30% of that from wild-type (WT) GP64. Heat treatment (37 degrees C) did not further reduce fusion activity of GP64 constructs with a disrupted intermolecular disulfide bond, suggesting that the GP64

SUBMITTER: Li Z 

PROVIDER: S-EPMC2918989 | biostudies-literature | 2010 Sep

REPOSITORIES: biostudies-literature