The paramyxovirus fusion protein (F) promotes fusion of the viral envelope with the plasma membrane of target cells as well as cell-cell fusion. The plasma membrane is closely associated with the actin cytoskeleton, but the role of actin dynamics in paramyxovirus F-mediated membrane fusion is unclear. We examined cell-cell fusion promoted by two different paramyxovirus F proteins in three cell types in the presence of constitutively active Rho family GTPases, major cellular coordinators of actin dynamics. Reporter gene and syncytia assays demonstrated that expression of either Rac1V12 or Cdc42V12 could increase cell-cell fusion promoted by the Hendra or SV5 glycoproteins, though the effect was dependent on the cell type expressing the viral glycoproteins. In contrast, RhoAL63 decreased cell-cell fusion promoted by Hendra glycoproteins but had little affect on SV5 F-mediated fusion. Also, data suggested that GTPase activation in the viral glycoprotein-containing cell was primarily responsible for changes in fusion. Additionally, we found that activated Cdc42 promoted nuclear rearrangement in syncytia.
|Number of pages
|Published - Jul 5 2006
Bibliographical noteFunding Information:
We thank Lin-Fa Wang of the Australian Animal Health Laboratory for the Hendra virus F and G plasmids, Robert Lamb (HHMI, Northwestern University) for the pCAGGS-SV5 F and HN expression plasmids, Richard Randall (University of St Andrews, Fife, UK) for the SV5 F-specific antibodies, and Karl-Klaus Conzelmann (Max Pettenkofer Institut) for kindly providing the BSR cells. Also, we thank Doug Andres (University of Kentucky) for the pCMV5M-GTPase plasmids as well as for his helpful discussion. We are grateful to the members of the Dutch laboratory who critically reviewed the manuscript. This study was partially supported by NIH grants A51517 (R.E.D.) and COBRE-P20RR20171 (R.O.M.).
- Membrane fusion
- Rho GTPase
ASJC Scopus subject areas