Paramyxovirus fusion (F) proteins promote both virus-cell fusion, required for viral entry, and cell-cell fusion, resulting in syncytia formation. We used the F-actin stabilizing drug, jasplakinolide, and the G-actin sequestrant, latrunculin A, to examine the role of actin dynamics in cell-cell fusion mediated by the parainfluenza virus 5 (PIV5) F protein. Jasplakinolide treatment caused a dose-dependent increase in cell-cell fusion as measured by both syncytia and reporter gene assays, and latrunculin A treatment also resulted in fusion stimulation. Treatment with jasplakinolide or latrunculin A partially rescued a fusion pore opening defect caused by deletion of the PIV5 F protein cytoplasmic tail, but these drugs had no effect on fusion inhibited at earlier stages by either temperature arrest or by a PIV5 heptad repeat peptide. These data suggest that the cortical actin cytoskeleton is an important regulator of fusion pore enlargement, an energetically costly stage of viral fusion protein-mediated membrane merger.
|Number of pages||10|
|State||Published - Aug 2010|
Bibliographical noteFunding Information:
We are grateful to members of the Dutch lab for critically reviewing this manuscript. Imaging studies were funded in part due to grants for the imaging facility provided by NIH COBRE grant P20RR20171 . This study was supported by NIAID grant R01A151517 to R.E.D., NEI grant R21 YE018112 to CLM, and NIH grant P20RR20171 to ROM.
- Fusion protein
- Membrane fusion
ASJC Scopus subject areas