1. Paramyxovirus F1 protein has two fusion peptides: implications for the mechanism of membrane fusion
- Author
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S G, Peisajovich, O, Samuel, and Y, Shai
- Subjects
Pam, phenylacetamido-methyl ,viruses ,Molecular Sequence Data ,membrane fusion ,PBS, phosphate-buffered saline ,DMSO, dimethyl sulfoxide ,PE, phosphatidylethanolamine ,PG, phosphatidylglycerol ,Models, Biological ,Protein Structure, Secondary ,Respirovirus ,Article ,TFA, trifluoroacetic acid ,Structure-Activity Relationship ,Rho, tetra-methylrhodamine ,RP-HPLC, reverse phase high-performance liquid chromatography ,Amino Acid Sequence ,NMR, nuclear magnetic resonance ,CD, circular dichroism ,SIV, simian immunodeficiency virus ,RET, resonance energy transfer ,Sequence Homology, Amino Acid ,paramyxoviridae ,Circular Dichroism ,PC, egg phosphatidylcholine ,NBD-F, 4-fluoro-7-nitrobenz-2-oxa-1,3-diazole ,LUV, large unilamellar vesicles ,Lipid Metabolism ,Peptide Fragments ,HIV, human immunodeficiency virus ,Microscopy, Electron ,Spectrometry, Fluorescence ,HF, hydrogen fluoride ,Liposomes ,Vacuoles ,BOC, butyloxycarbonyl ,Thermodynamics ,fusion peptide ,viral entry ,fluorescence ,RSV, respiratory syncytial virus ,Endopeptidase K ,Dimerization ,Viral Fusion Proteins ,SUV, small unilamellar vesicles ,Protein Binding - Abstract
Viral fusion proteins contain a highly hydrophobic segment, named the fusion peptide, which is thought to be responsible for the merging of the cellular and viral membranes. Paramyxoviruses are believed to contain a single fusion peptide at the N terminus of the F1 protein. However, here we identified an additional internal segment in the Sendai virus F1 protein (amino acids 214–226) highly homologous to the fusion peptides of HIV-1 and RSV. A synthetic peptide, which includes this region, was found to induce membrane fusion of large unilamellar vesicles, at concentrations where the known N-terminal fusion peptide is not effective. A scrambled peptide as well as several peptides from other regions of the F1 protein, which strongly bind to membranes, are not fusogenic. The functional and structural characterization of this active segment suggest that the F1 protein has an additional internal fusion peptide that could participate in the actual fusion event. The presence of homologous regions in other members of the same family suggests that the concerted action of two fusion peptides, one N-terminal and the other internal, is a general feature of paramyxoviruses.
- Published
- 2000