Stable formation of compositionally unique stress granules in virus-infected cells.
Stress granules are sites of mRNA storage formed in response to a variety of stresses, including viral infections. Here, the mechanisms and consequences of stress granule formation during poliovirus infection were examined. The results indicate that stress granules containing T-cell-restricted intracellular antigen 1 (TIA-1) and mRNA are stably constituted in infected cells despite lacking intact RasGAP SH3-domain binding protein 1 (G3BP) and eukaryotic initiation factor 4G. Fluorescent in situ hybridization revealed that stress granules in infected cells do not contain significant amounts of viral positive-strand RNA. Infection does not prevent stress granule formation in response to heat shock, indicating that poliovirus does not block de novo stress granule formation. A mutant TIA-1 protein that prevents stress granule formation during oxidative stress also prevents formation in infected cells. However, stress granule formation during infection is more dependent upon ongoing transcription than is formation during oxidative stress or heat shock. Furthermore, Sam68 is recruited to stress granules in infected cells but not to stress granules formed in response to oxidative stress or heat shock. These results demonstrate that stress granule formation in poliovirus-infected cells utilizes a transcription-dependent pathway that results in the appearance of stable, compositionally unique stress granules.
Piotrowska
Joanna
J
University of Arizona College of Medicine-Phoenix, Department of Basic Medical Sciences, 425 N. Fifth Street, ABC1 Room 328, Phoenix, AZ 85004, USA.
Hansen
Spencer J
SJ
Park
Nogi
N
Jamka
Katarzyna
K
Sarnow
Peter
P
Gustin
Kurt E
KE
D003594:Cytoplasmic Granules / Q000378:metabolism*; D015852:Eukaryotic Initiation Factor-2 / Q000378:metabolism; D055551:HSP27 Heat-Shock Proteins / Q000502:physiology; D006367:HeLa Cells; D006360:Heat-Shock Proteins; D018869:Heat-Shock Response; D006801:Humans; D018832:Molecular Chaperones; D010766:Phosphorylation; D017955:Poliovirus / Q000502:physiology*; D039102:Poly(A)-Binding Proteins / Q000032:analysis / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D000074019:T-Cell Intracellular Antigen-1; D014158:Transcription, Genetic
D015852:Eukaryotic Initiation Factor-2; D055551:HSP27 Heat-Shock Proteins; C057725:HSPB1 protein, human; D006360:Heat-Shock Proteins; D018832:Molecular Chaperones; D039102:Poly(A)-Binding Proteins; D012333:RNA, Messenger; D000074019:T-Cell Intracellular Antigen-1; C071558:TIA1 protein, human