Poliovirus infection effects the formation of stress granules, which shelter mRNAs when cells are subjected to stress, report researchers from Baylor College of Medicine.
“When the cell suffers a major insult, it stops expanding. The business of protein synthesis is arrested. mRNA goes into storage until conditions improve for the cells, and stress granules are a major storage site for the mRNA,” explains Richard Lloyd, Ph.D., associate professor of molecular virology and microbiology and senior author of the paper.
In poliovirus infection, the stress granules are formed early. As the infection continues, however, these granules disperse. The scientists found that the poliovirus infection, which was used because it is a prototype for many kinds of viruses, actually cleaves G3BP, a protein critical in the formation of the stress granules.
When the investigators mutated G3BP to make it resistant to being cut, they found that stress granules could be formed during virus infection and that this inhibited virus growth in the cells.
Dr. Llyod believes that other viruses may affect other proteins important in this type of stress response.
The study appears in the November 14 issue of Cell Host and Microbe.