THE US3 PROTEIN-KINASE OF HERPES-SIMPLEX VIRUS TYPE-2 IS ASSOCIATED WITH PHOSPHORYLATION OF THE UL12 ALKALINE NUCLEASE IN-VITRO

Herpes simplex virus type 2 (HSV-2) gene US3 encodes a serine-threonin e protein kinase. We previously described the isolation of a US3-inact ivated mutant which is able to replicate in Vero cells but not in muri ne macrophages. To learn more about the biological role of the US3 pro tein kinase, we have sought to identify the target proteins of the enz yme. Studies of in vitro phosphorylation with extracts of infected cel ls demonstrate that the US3 protein kinase is involved in phosphorylat ion of the UL12 alkaline nuclease in vitro, suggesting that the nuclea se is a possible target of the protein kinase.