Evidence that selective changes in the lipid composition of raft-membranes occur during respiratory syncytial virus infection.
We examined the structure of lipid-raft membranes in respiratory syncytial virus infected cells. Cholesterol depletion studies using methyl-beta-cyclodextrin suggested that membrane cholesterol was required for virus filament formation, but not inclusion bodies. In addition, virus filament formation coincided with elevated 3-hydroxy-3-methylglutaryl-coenzyme A reductase expression, suggesting an increase in requirement for endogenous cholesterol synthesis during virus assembly. Lipid raft membranes were examined by mass spectrometry, which suggested that virus infection induced subtle changes in the lipid composition of these membrane structures. This analysis revealed increased levels of raft-associated phosphatidylinositol (PI) and phosphorylated PI during RSV infection, which correlated with the appearance of phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 3,4,5-triphosphate (PIP(3)) within virus inclusion bodies, and inhibiting the synthesis of PIP(3) impaired the formation of progeny virus. Collectively, our analysis suggests that RSV infection induces specific changes in the composition of raft-associated lipids, and that these changes play an important role in virus maturation.
Yeo
Dawn Su-Yin
DS
Division of Molecular and Cell Biology, School of Biological Sciences, Nanyang Technological University, Nanyang Drive, Singapore, 637551, Singapore.
Chan
Robin
R
Brown
Gaie
G
Ying
Li
L
Sutejo
Richard
R
Aitken
Jim
J
Tan
Boon-Huan
BH
Wenk
Markus R
MR
Sugrue
Richard J
RJ
D002460:Cell Line; D006801:Humans; D025782:Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent / Q000378:metabolism; D007181:Inclusion Bodies, Viral / Q000737:chemistry; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis*; D013058:Mass Spectrometry; D021962:Membrane Microdomains / Q000737:chemistry*; D012136:Respiratory Syncytial Viruses / Q000502:physiology*; D019065:Virus Assembly
D008055:Lipids; D025782:Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent