HERPES-SIMPLEX VIRUS US11 PROTEIN ENHANCES RECOVERY OF PROTEIN-SYNTHESIS AND SURVIVAL IN HEAT-SHOCK TREATED HELA-CELLS

One of the herpes simplex virus type 1 (HSV-1) true late gene products , Us11 protein, is brought into the cell by the infecting virion and m ay play a role in the virally-induced post-transcriptional control of gene expression. Us11 protein forms large oligomers, exhibits RNA bind ing features, concentrates into the nucleolus and is able to replace R ex protein in post-transcriptional control of human T-cell leukemia/ly mphoma virus type [ (HTLV-I) expression. As heat shock drastically alt ers protein synthesis, and because HSV-1 infection stimulates heat sho ck protein (Hsp) expression, we analyzed the consequence of heat shock in HeLa cells expressing Us11 alone, either transiently or constituti vely. No detectable modification of the overall pattern of protein syn thesis was observed in cells growing at normal temperatures, including no induction of Hsp expression or accumulation. However, Us11 protein expression induced an enhanced recovery of protein synthesis after he at shock. Moreover, the level of Us11 protein-mediated protection of p rotein synthesis was similar to that observed for cells made thermotol erant, but only when submitted to a mild heat shock. Finally, Us11 pro tein expression induced in cells an enhanced survival to heat shock.