Abstract
The alphavirus Semliki Forest virus (SFV) infects cells through low-pH-induced membrane fusion mediated by the E1 protein, a class II virus membrane fusion protein. During fusion, E1 inserts into target membranes via its hydrophobic fusion loop and refolds to form a stable E1 homotrimer. Mutation of a highly conserved histidine (the H230A mutation) within a loop adjacent to the fusion loop was previously shown to block SFV fusion and infection, although the mutant E1 protein still inserts into target membranes and forms a homotrimer. Here we report on second-site mutations in E1 that rescue the H230A mutant. These mutations were located in a cluster within the hinge region, at the membrane-interacting tip, and within the groove where the E1 stem is believed to pack. Together the revertants reveal specific and interconnected aspects of the fusion protein refolding reaction.
Original language | English (US) |
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Pages (from-to) | 6115-6122 |
Number of pages | 8 |
Journal | Journal of virology |
Volume | 80 |
Issue number | 12 |
DOIs | |
State | Published - Jun 2006 |
ASJC Scopus subject areas
- Microbiology
- Immunology
- Insect Science
- Virology