Stress-induced increase of hexose transport as a novel index of cytopathic effects in virus-infected cells: role of the L protein in the action of vesicular stomatitis virus.
The VSV-specific increase in hexose transport by BHK cells has been measured by assay of the [3H]dGlc/[14C]AIB uptake ratio. The effect was abolished by uv-irradiation of the virus, indicating that viral gene expression is required. Cells infected with the T1026 R1 mutant of VSV, which causes only slight cytopathic changes, exhibited only a slight increase in hexose uptake. Cells infected with temperature-sensitive (ts) mutants of VSV that are defective in the function of the viral N, NS, G, or M proteins at the restrictive temperature (39.5 degrees) exhibited increased [3H]dGLC/[14C]AIB uptake ratios typical of wild-type virus at either restrictive (39.5 degrees) or permissive temperature (34 degrees). Cells infected with a mutant defective in the function of the viral L protein exhibited an increased [3H]dGlc/[14C]AIB uptake ratio at permissive temperature (34 degrees) only; at restrictive temperature (39.5 degrees) the uptake ratio was essentially the same as that of mock-infected cells. Temperature-shift experiments indicated that the effect on hexose transport persisted for at least 6 hr in cells which no longer expressed function L protein, and that when expression of L was restricted to the first 2 hr of infection, an almost complete stimulation of hexose transport was observed 4 hr later. These results indicate that expression of the L gene is a necessary factor for inducing an increased hexose uptake in VSV-infected BHK cells. They also suggest that the action of the L protein on hexose transport is indirect, and is presumably mediated by other cellular constituents. The studies support the concept that an increased dGlc uptake may be a useful index of the cytopathic consequences of virus infection.
Pasternak
C A
CA
Department of Biochemistry, St. George's Hospital Medical School, London, United Kingdom.
Whitaker-Dowling
P A
PA
Widnell
C C
CC
D000818:Animals; D001151:Arsenic / Q000494:pharmacology; D018053:Arsenites; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D006224:Cricetinae; D003513:Cycloheximide / Q000494:pharmacology; D003588:Cytopathogenic Effect, Viral; D003837:Deoxy Sugars / Q000378:metabolism*; D003847:Deoxyglucose / Q000378:metabolism*; D009154:Mutation; D012324:RNA-Dependent RNA Polymerase; D013696:Temperature; D014721:Vesicular stomatitis Indiana virus; D014764:Viral Proteins / Q000502:physiology*; D014777:Virus Diseases / Q000378:metabolism*
D018053:Arsenites; D003837:Deoxy Sugars; D014764:Viral Proteins; D003513:Cycloheximide; D003847:Deoxyglucose; C040530:L protein, vesicular stomatitis virus; D012324:RNA-Dependent RNA Polymerase; C015001:arsenite; D001151:Arsenic