Phospholipid synthesis in human embryo fibroblasts infected with herpes simplex virus type 2

The effect of herpes simplex virus type 2 infection on the synthesis of phospholipids in human embryo fibroblasts was determined at temperatures permissive (35 C) or nonpermissive (42 C) for virus replication. Incorporation of [32P]i was decreased by herpes simplex virus type 2 infection after 6 hr, which corresponds to the time of initiation of progeny virus production. No differences were observed in the relative incorporation of [32P]i phospholipid classes. In another series of experiments cells were labeled with [3H]ethanolamine before infection and with [14C]ethanolamine after infection. The incorporation of [14C]ethanolamine was also decreased after 6 hr of infection. When choline was substituted for ethanolamine, a similar, although less pronounced, decrease in incorporation was seen in infected cells compared to mock-infected cells. During abortive infections at 42 C, incorporation of [3H]thymidine into cellular DNA was stimulated, but the incorporation of phospholipid precursors was decreased. Total phospholipid composition and phospholipid acyl group composition were not changed appreciably during abortive or productive infection, regardless of whether the cells were labeled before or after infection. In conclusion, these data indicated that, during herpes simplex virus type 2 infection, the incorporation of lipid precursors into phospholipid was decreased. The stimulation of cellular DNA synthesis previously observed during abortive infection at 42 C was not paralleled by a detectable stimulation of total phospholipid synthesis. Neither productive nor abortive infection resulted in significant phospholipid compositional changes in the host cell; however, both resulted in a marked inhibition of phospholipid synthesis.